MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'IEE Transactions on Neural Systems and Rehabilitation Engineering' source. Tue, 07 Feb 2012 07:05:43 +0100 http://www.medworm.com/index.php?rid=5626095&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6132634 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626095 Sun, 01 Jan 2012 05:00:00 +0100 5626095 http://www.medworm.com/index.php?rid=5626094&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6132636 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626094 Sun, 01 Jan 2012 05:00:00 +0100 5626094 http://www.medworm.com/index.php?rid=5626093&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6112238 The P300-based speller is a well-established brain–computer interface for communication. It displays a matrix of objects on the computer screen, flashes each object in sequence, and looks for a P300 response induced by flashing the desired object. Most existing P300 spellers uses a fixed set of flash objects. We demonstrate that performance can be significantly improved by sequential selections from a hierarchy of flash sets containing variable number of objects. Theoretically, the optimal hierarchy of flash sets—with respect to a given statistical language model—can be found by solving a stochastic control problem of low computational complexity. Experimentally, statistical analysis demonstrates that the average time per output character at 85% accuracy is reduced by ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626093 Sun, 01 Jan 2012 05:00:00 +0100 5626093 http://www.medworm.com/index.php?rid=5626092&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6104159 Electrical stimulation of arm and hand muscles can be a functional tool for patients with motor dysfunction. Sufficient stimulation of finger and thumb musculature can support natural grasping function. Yet it remains unclear how different grasping movements can be selectively supported by electrical stimulation. The goal of this study is to determine to what extent activation of individual fingers is possible with surface electrical stimulation for the purpose of rehabilitation following stroke. The extensor digitorum communis (EDC) muscle, flexor pollicis longus (FPL) muscle, and the thenar muscle group, all involved in grasp and release, were selected for stimulation. The evoked forces in individual fingers were measured. Stimulation thresholds and selective ranges were determined for e... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626092 Sun, 01 Jan 2012 05:00:00 +0100 5626092 http://www.medworm.com/index.php?rid=5626091&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6114258 Intracortical microstimulation (ICMS) has promise as a means for delivering somatosensory feedback in neuroprosthetic systems. Various tactile sensations could be encoded by temporal, spatial, or spatiotemporal patterns of ICMS. However, the applicability of temporal patterns of ICMS to artificial tactile sensation during active exploration is unknown, as is the minimum discriminable difference between temporally modulated ICMS patterns. We trained rhesus monkeys in an active exploration task in which they discriminated periodic pulse-trains of ICMS (200 Hz bursts at a 10 Hz secondary frequency) from pulse trains with the same average pulse rate, but distorted periodicity (200 Hz bursts at a variable instantaneous secondary frequency). The statistics of the aperiodic pulse trains were draw... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626091 Sun, 01 Jan 2012 05:00:00 +0100 5626091 http://www.medworm.com/index.php?rid=5626090&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6035792 This study investigated the regional cortical activities detected by functional near infrared spectroscopy (fNIRS) in 12 healthy young and 13 healthy elderly subjects under conditions of cycling without-(free cycling) and with feedback (target cycling). The elderly exhibited predominant activation of the sensorimotor cortex during free cycling similar to young subjects but with poorer cycling performance. The cycling performance improved in both groups, and the elderly showed increased brain activities of the supplementary motor area and premotor cortex under target cycling condition. These findings demonstrated age-related changes in the cortical control in processing external feedback and pedaling movements. Use of fNIRS to evaluate brain activation patterns after training may facilitate... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626090 Sun, 01 Jan 2012 05:00:00 +0100 5626090 http://www.medworm.com/index.php?rid=5626089&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6132638 A new method of lower-limb exoskeleton control aimed at improving the agility of leg-swing motion is presented. In the absence of control, an exoskeleton's mechanism usually hinders agility by adding mechanical impedance to the legs. The uncompensated inertia of the exoskeleton will reduce the natural frequency of leg swing, probably leading to lower step frequency during walking as well as increased metabolic energy consumption. The proposed controller emulates inertia compensation by adding a feedback loop consisting of low-pass filtered angular acceleration multiplied by a negative gain. This gain simulates negative inertia in the low-frequency range. The resulting controller combines two assistive effects: increasing the natural frequency of the lower limbs and performing net work per ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626089 Sun, 01 Jan 2012 05:00:00 +0100 5626089 http://www.medworm.com/index.php?rid=5626088&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6101579 This paper presents the design and preliminary experimental validation of a multigrasp myoelectric controller. The described method enables direct and proportional control of multigrasp prosthetic hand motion among nine characteristic postures using two surface electromyography electrodes. To assess the efficacy of the control method, five nonamputee subjects utilized the multigrasp myoelectric controller to command the motion of a virtual prosthesis between random sequences of target hand postures in a series of experimental trials. For comparison, the same subjects also utilized a data glove, worn on their native hand, to command the motion of the virtual prosthesis for similar sequences of target postures during each trial. The time required to transition from posture to posture and the... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626088 Sun, 01 Jan 2012 05:00:00 +0100 5626088 http://www.medworm.com/index.php?rid=5626087&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6107615 Both the American Heart Association and the VA/DoD endorse upper-extremity robot-mediated rehabilitation therapy for stroke care. However, we do not know yet how to optimize therapy for a particular patient's needs. Here, we explore whether we must train patients for each functional task that they must perform during their activities of daily living or alternatively capacitate patients to perform a class of tasks and have therapists assist them later in translating the observed gains into activities of daily living. The former implies that motor adaptation is a better model for motor recovery. The latter implies that motor learning (which allows for generalization) is a better model for motor recovery. We quantified trained and untrained movements performed by 158 recovering stroke patient... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626087 Sun, 01 Jan 2012 05:00:00 +0100 5626087 http://www.medworm.com/index.php?rid=5626086&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6096433 Hammersmith Infant Neurological Examination (HINE) is a set of tests used for grading neurological development of infants on a scale of 0 to 3. These tests help in assessing neurophysiological development of babies, especially preterm infants who are born before (the fetus reaches) the gestational age of 36 weeks. Such tests are often conducted in the follow-up clinics of hospitals for grading infants with suspected disabilities. Assessment based on HINE depends on the expertise of the physicians involved in conducting the examinations. It has been noted that some of these tests, especially pulled-to-sit and lateral tilting, are difficult to assess solely based on visual observation. For example, during the pulled-to-sit examination, the examiner needs to observe the relative movement of t... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626086 Sun, 01 Jan 2012 05:00:00 +0100 5626086 http://www.medworm.com/index.php?rid=5626085&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6042340 Incorporating sensory feedback with prosthetic devices is now possible, but the optimal methods of providing such feedback are still unknown. The relative utility of amplitude and pulse train frequency modulated stimulation paradigms for providing vibrotactile feedback for object manipulation was assessed in 10 participants. The two approaches were studied during virtual object manipulation using a robotic interface as a function of presentation order and a simultaneous cognitive load. Despite the potential pragmatic benefits associated with pulse train frequency modulated vibrotactile stimulation, comparison of the approach with amplitude modulation indicates that amplitude modulation vibrotactile stimulation provides superior feedback for object manipulation. (Source: IEE Transactions on... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626085 Sun, 01 Jan 2012 05:00:00 +0100 5626085 http://www.medworm.com/index.php?rid=5626084&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6109353 This paper quantifies and comparatively validates functional connectivity between neurons by measuring the statistical dependence between their firing rates. Based on statistical analysis of the pairwise functional connectivity, we estimate, exclusively from neural data, the neural assembly functional connectivity given a behavior task, which provides a quantifiable representation of the dynamic nature during the behavioral task. Because of the time scale of behavior (100–1000 ms), a statistical method that yields robust estimators for this small sample size is desirable. In this work, the temporal resolutions of four estimators of functional connectivity are compared on both simulated data and real neural ensemble recordings. The comparison highlights how the properties and assumpt... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626084 Sun, 01 Jan 2012 05:00:00 +0100 5626084 http://www.medworm.com/index.php?rid=5626083&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6101580 The oddball protocol is often used in brain–computer interfaces (BCIs) to induce P300 ERPs, although, recently, some issues have been shown to detrimentally effect its performance. In this paper, we study a new periodic protocol and explore whether it can compete with the standard oddball protocol within the context of a BCI mouse. We found that the new protocol consistently and significantly outperforms the standard oddball protocol in relation to information transfer rates (33 bits/min for the former and 22 bits/min for the latter, measured at 90% accuracy) as well as P300 amplitudes. Furthermore, we performed a comparison of two periodic protocols with two less conventional oddball-like protocols that reveals the importance of the interactions between task and sequence in determi... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626083 Sun, 01 Jan 2012 05:00:00 +0100 5626083 http://www.medworm.com/index.php?rid=5626082&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6044720 This paper presents an algorithm based on neural networks and fuzzy theory (S-dFasArt) to classify spontaneous mental activities from electroencephalogram (EEG) signals, in order to operate a noninvasive brain–computer interface. The focus is placed on the three-class problem, left-hand movement imagination, right movement imagination and word generation. The algorithm allows a supervised classification of temporal patterns improving the classification rates of the BCI Competition III (Data Set V: multiclass problem, continuous EEG). Using the precomputed data supplied for the competition and following the rules established there, a new method based on S-dFasArt, along with rule prune and voting strategy is proposed. The results have been compared with other published methods improv... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626082 Sun, 01 Jan 2012 05:00:00 +0100 5626082 http://www.medworm.com/index.php?rid=5626081&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6132639 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626081 Sun, 01 Jan 2012 05:00:00 +0100 5626081 http://www.medworm.com/index.php?rid=5626080&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6132637 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626080 Sun, 01 Jan 2012 05:00:00 +0100 5626080 http://www.medworm.com/index.php?rid=5626079&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6132633%26arnumber%3D6132635 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5626079 Sun, 01 Jan 2012 05:00:00 +0100 5626079 http://www.medworm.com/index.php?rid=5502564&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6095870 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5502564 Thu, 01 Dec 2011 05:00:00 +0100 5502564 http://www.medworm.com/index.php?rid=5484712&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6094272 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484712 Thu, 01 Dec 2011 05:00:00 +0100 5484712 http://www.medworm.com/index.php?rid=5484711&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6094273 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484711 Thu, 01 Dec 2011 05:00:00 +0100 5484711 http://www.medworm.com/index.php?rid=5484710&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6044721 In conclusion, the implantable sensor performs similar to the reference sensor when used to detect the onset of bladder contractions. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484710 Thu, 01 Dec 2011 05:00:00 +0100 5484710 http://www.medworm.com/index.php?rid=5484709&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6034529 Precise positioning of a stimulating electrode in the eye is not possible by simple visualization. However, reliable measurement of responses to retinal stimulation requires consistent positioning. The present study focuses on impedance measurement techniques to sense the proximity of the electrode to the retina. A platinum-iridium stimulation electrode was placed inside the rat eye and impedance was recorded at different positions of the stimulating electrode relative to the retina. The presence of robust electrically evoked response in the superior colliculus indicates that the electrode may not have to be in absolute contact in order to elicit a neural response. Optical coherence tomography imaging confirmed the distance-impedance relationship. (Source: IEE Transactions on Neural System... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484709 Thu, 01 Dec 2011 05:00:00 +0100 5484709 http://www.medworm.com/index.php?rid=5484708&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6035988 To date, research on the motor control of hand function in cerebral palsy has focused on children with hemiplegia, although many persons with diplegic cerebral palsy (dCP) have asymmetrically decreased hand function. We explored the predictive capabilities of the motor system in a simple motor task of lifting a series of virtual objects for five persons with spastic dCP and five age-matched controls. When a person lifts an object, s/he uses an expectation of the weight of the object to generate a motor command. We asked the study subjects to lift a series of increasing weights and determined whether they extrapolated from past experience to predict the next weight in the series, even though that weight had never been experienced. Planning of precision grasp was assessed by measurement of t... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484708 Thu, 01 Dec 2011 05:00:00 +0100 5484708 http://www.medworm.com/index.php?rid=5484707&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6035990 Most hand prostheses do not provide intentional haptic feedback about movement performance; thus users must rely almost completely on visual feedback. This paper focuses on understanding the effects of learning and different stimulation sites when vibrotactile stimulation is used as the intentional haptic feedback. Eighteen unimpaired individuals participated in this study with a robotic interface to manipulate a virtual object with visual and vibrotactile feedback at four body sites (finger, arm, neck, and foot) presented in a random order. All participants showed improvements in object manipulation performance with the addition of vibrotactile feedback. Specifically, performance showed a strong learning effect across time, with learning transferring across different sites of vibrotactile... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484707 Thu, 01 Dec 2011 05:00:00 +0100 5484707 http://www.medworm.com/index.php?rid=5484706&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D5995172 Falls are the number one cause of injury in older adults. Wearable sensors, typically consisting of accelerometers and/or gyroscopes, represent a promising technology for preventing and mitigating the effects of falls. At present, the goal of such “ambulatory fall monitors” is to detect the occurrence of a fall and alert care providers to this event. Future systems may also provide information on the causes and circumstances of falls, to aid clinical diagnosis and targeting of interventions. As a first step towards this goal, the objective of the current study was to develop and evaluate the accuracy of a wearable sensor system for determining the causes of falls. Sixteen young adults participated in experimental trials involving falls due to slips, trips, and “other&#... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484706 Thu, 01 Dec 2011 05:00:00 +0100 5484706 http://www.medworm.com/index.php?rid=5484705&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D5993546 In conclusion, we developed a bilateral ankle perturbator which is able to apply support surface rotations to both ankles independently. The major application of the device will be to investigate the contribution of both ankles to human balance control, and the interactions in balance control between both legs. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484705 Thu, 01 Dec 2011 05:00:00 +0100 5484705 http://www.medworm.com/index.php?rid=5484704&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6033046 This paper describes a powered lower-limb orthosis that is intended to provide gait assistance to spinal cord injured (SCI) individuals by providing assistive torques at both hip and knee joints. The orthosis has a mass of 12 kg and is capable of providing maximum joint torques of 40 Nm with hip and knee joint ranges of motion from 105$^{circ}$ flexion to 30 $^{circ}$ extension and 105 $^{circ}$ flexion to 10 $^{circ}$ hyperextension, respectively. A custom distributed embedded system controls the orthosis with power being provided by a lithium polymer battery which provides power for one hour of continuous walking. In order to demonstrate the ability of the orthosis to assist walking, the orthosis was experimentally implemented on a paraplegic subject with a T10 complete injury. Data coll... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484704 Thu, 01 Dec 2011 05:00:00 +0100 5484704 http://www.medworm.com/index.php?rid=5484703&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D5985538 Reported studies on pattern recognition of electromyograms (EMG) for the control of prosthetic devices traditionally focus on classification accuracy of signals recorded in a laboratory. The difference between the constrained nature in which such data are often collected and the unpredictable nature of prosthetic use is an example of the semantic gap between research findings and a viable clinical implementation. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484703 Thu, 01 Dec 2011 05:00:00 +0100 5484703 http://www.medworm.com/index.php?rid=5484702&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6034527 Intermuscular coherence can identify oscillatory coupling between two electromyographic (EMG) signals, measuring common presynaptic drive to motor neurons. Beta band oscillations (15–30 Hz) are hypothesized to originate largely from primary motor cortex, and are reduced during dynamic relative to static motor tasks. It has yet to be established whether motor imagery modulates beta intermuscular coherence. Using visual feedback, 10 unimpaired participants completed eighteen trials of pinching their right thumb and index finger at a constant force. During the 60-second trials, participants simultaneously engaged in one of three types of kinesthetic imagery: the right thumb and index finger executing a constant force pinch (static), the fingers of the right hand sequentially flexing an... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484702 Thu, 01 Dec 2011 05:00:00 +0100 5484702 http://www.medworm.com/index.php?rid=5484701&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6035793 Brain–computer interfaces (BCIs) are known to suffer from spontaneous changes in the brain activity. If changes in the mental state of the user are reflected in the brain signals used for control, the behavior of a BCI is directly influenced by these states. We investigate the influence of a state of loss of control in a variant of Pacman on the performance of BCIs based on motor control. To study the effect a temporal loss of control has on the BCI performance, BCI classifiers were trained on electroencephalography (EEG) recorded during the normal control condition, and the classification performance on segments of EEG from the normal and loss of control condition was compared. Classifiers based on event-related desynchronization unexpectedly performed significantly better during t... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484701 Thu, 01 Dec 2011 05:00:00 +0100 5484701 http://www.medworm.com/index.php?rid=5484700&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6034528 This study aims to find a minimal set of electrodes for an individual stroke subject for motor imagery to control an assistive device using functional electrical stimulation for 20 sessions with accuracy higher than 90%. The characteristics of this minimal electrode set were evaluated with two popular algorithms: Fisher's criterion and support-vector machine recursive feature elimination (SVM-RFE). The number of calibration sessions for channel selection required for robust control of these 20 sessions was also investigated. Five chronic stroke patients were recruited for the study. Our results suggested that the number of calibration sessions for channel selection did not have a significant effect on the classification accuracy. A performance index devised in this study showed that one tr... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484700 Thu, 01 Dec 2011 05:00:00 +0100 5484700 http://www.medworm.com/index.php?rid=5484699&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D5995171 A new form of deep brain stimulation (DBS) electrode was proposed that was made of carbon nanotube yarns (CNTYs). Electrode interface properties were examined using cyclic voltammetry (CV) and electrochemical impedance spectrum (EIS). The CNTY electrode interface exhibited large charge storage capacity (CSC) of ${hbox{12.3}}~{hbox{mC}}/{hbox{cm}}^{2}$ which increased to $98.6~{hbox{mC}}/{hbox{cm}}^{2}$ after acid treatment, compared with $5.0~{hbox{mC}}/{hbox{cm}}^{2}$ of Pt–Ir. Impedance spectrum of both untreated and treated CNTY electrodes showed that finite diffusion process occurred at the interface due to their porous structure and charge was delivered through capacitive mechanism. To evaluate stability electrical stimulus was exerted for up to 72 h and CV and EIS results of C... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484699 Thu, 01 Dec 2011 05:00:00 +0100 5484699 http://www.medworm.com/index.php?rid=5484698&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6033048 Electromechanical delay (EMD) is a biological artifact that arises due to a time lag between electrical excitation and tension development in a muscle. EMD is known to cause degraded performance and instability during neuromuscular electrical stimulation (NMES). Compensating for such input delay is complicated by the unknown nonlinear muscle force-length and muscle force-velocity relationships. This paper provides control development and a mathematical stability analysis of a NMES controller with a predictive term that actively accounts for EMD. The results are obtained through the development of a novel predictor-type method to address the delay in the voltage input to the muscle. Lyapunov-Krasovskii functionals are used within a Lyapunov-based stability analysis to prove semi-global unif... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484698 Thu, 01 Dec 2011 05:00:00 +0100 5484698 http://www.medworm.com/index.php?rid=5484697&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6094274 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484697 Thu, 01 Dec 2011 05:00:00 +0100 5484697 http://www.medworm.com/index.php?rid=5484696&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6086695%26arnumber%3D6094289 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5484696 Thu, 01 Dec 2011 05:00:00 +0100 5484696 http://www.medworm.com/index.php?rid=5312153&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6036731 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312153 Sat, 01 Oct 2011 04:00:00 +0100 5312153 http://www.medworm.com/index.php?rid=5312152&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6036732 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312152 Sat, 01 Oct 2011 04:00:00 +0100 5312152 http://www.medworm.com/index.php?rid=5312151&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6036736 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312151 Sat, 01 Oct 2011 04:00:00 +0100 5312151 http://www.medworm.com/index.php?rid=5312150&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6036738 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312150 Sat, 01 Oct 2011 04:00:00 +0100 5312150 http://www.medworm.com/index.php?rid=5312149&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5986721 We describe a new multichannel vestibular prosthesis (MVP) intended to restore modulation of vestibular nerve activity with head rotation. The device comprises motion sensors to measure rotation and gravitoinertial acceleration, a microcontroller to calculate pulse timing, and stimulator units that deliver constant-current pulses to microelectrodes implanted in the labyrinth. This new MVP incorporates many improvements over previous prototypes, including a 50% decrease in implant size, a 50% decrease in power consumption, a new microelectrode array design meant to simplify implantation and reliably achieve selective nerve–electrode coupling, multiple current sources conferring ability to simultaneously stimulate on multiple electrodes, and circuitry for in vivo measurement of electr... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312149 Sat, 01 Oct 2011 04:00:00 +0100 5312149 http://www.medworm.com/index.php?rid=5312148&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5985539 Changes in surface electromyogram (sEMG) spectral content are commonly associated with localized muscle fatigue. However, the significance of the changes is only evident during pair-wise comparison and these can only be used for comparison between the rested and fatigued muscle and cannot be used for identifying the limit of muscle endurance without having the rested data for comparison. This is due to the large variations between sEMG at different levels of strengths of contraction, and between different people. This is further compounded when the contraction is not isometric but is cyclic because there is large variation of sEMG within each cycle. This research has developed a new sEMG based method for studying muscle fatigue and for identifying the limit of muscle endurance. It is based... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312148 Sat, 01 Oct 2011 04:00:00 +0100 5312148 http://www.medworm.com/index.php?rid=5312147&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5986722 This study aimed to 1) select potential stumble detection data sources that react reliably and quickly to stumbles and can be measured from a prosthesis, and 2) investigate two different approaches based on selected data sources to detect stumbles and classify stumble types in patients with transfemoral (TF) amputations during ambulation. In the experiments, the normal gait of TF amputees was perturbed by a controllable treadmill or when they walked on an obstacle course. The results showed that the acceleration of prosthetic foot can accurately detect the tested stumbling events 140-240 ms before the critical timing of falling and precisely classify the stumble type. However, the detector based on foot acceleration produced high false alarm rates, which challenged its real application. Co... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312147 Sat, 01 Oct 2011 04:00:00 +0100 5312147 http://www.medworm.com/index.php?rid=5312146&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5585779 This study demonstrated the feasibility of the EMG pattern classification technique to discern the intent of stroke survivors. Future work should concentrate on the construction of a subject-specific EMG classification paradigm that carefully considers both functional and physiological impairment characteristics of each subject in the target task selection and electrode placement procedures. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312146 Sat, 01 Oct 2011 04:00:00 +0100 5312146 http://www.medworm.com/index.php?rid=5312145&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5986720 Conduction block using high-frequency alternating current (HFAC) stimulation has been shown to reversibly block conduction through various nerves. However, unlike simulations and experiments on myelinated fibers, prior experimental work in our lab on the sea-slug, Aplysia, found a nonmonotonic relationship between frequency and blocking thresholds in the unmyelinated fibers. To resolve this discrepancy, we investigated the effect of HFAC waveforms on the compound action potential of the sciatic nerve of frogs. Maximal stimulation of the nerve produces a compound action potential consisting of the A-fiber and C-fiber components corresponding to the myelinated and unmyelinated fibers' response. In our study, HFAC waveforms were found to induce reversible block in the A-fibers and C-fibers fo... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312145 Sat, 01 Oct 2011 04:00:00 +0100 5312145 http://www.medworm.com/index.php?rid=5312144&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6035989 Event-related desynchronization (ERD) of sensori-motor rhythms (SMR) can be used for online brain–machine interface (BMI) control, but yields challenges related to the stability of ERD and feedback strategy to optimize BMI learning. Here, we compared two approaches to this challenge in 20 right-handed healthy subjects (HS, five sessions each, S1-S5) and four stroke patients (SP, 15 sessions each, S1-S15). ERD was recorded from a 275-sensor MEG system. During daily training, motor imagery-induced ERD led to visual and proprioceptive feedback delivered through an orthotic device attached to the subjects' hand and fingers. Group A trained with a heterogeneous reference value (RV) for ERD detection with binary feedback and Group B with a homogenous RV and graded feedback (10 HS and 2 SP... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312144 Sat, 01 Oct 2011 04:00:00 +0100 5312144 http://www.medworm.com/index.php?rid=5312143&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5872050 Neuroscience is just beginning to understand the neural computations that underlie our remarkable capacity to learn new motor tasks. Studies of natural movements have emphasized the importance of concepts such as dimensionality reduction within hierarchical levels of redundancy, optimization of behavior in the presence of sensorimotor noise and internal models for predictive control. These concepts also provide a framework for understanding the improvements in performance seen in myoelectric-controlled interface and brain–machine interface paradigms. Recent experiments reveal how volitional activity in the motor system combines with sensory feedback to shape neural representations and drives adaptation of behavior. By elucidating these mechanisms, a new generation of intelligent int... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312143 Sat, 01 Oct 2011 04:00:00 +0100 5312143 http://www.medworm.com/index.php?rid=5312142&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5986723 In bi-directional brain–machine interfaces (BMIs), precisely controlling the delivery of microstimulation, both in space and in time, is critical to continuously modulate the neural activity patterns that carry information about the state of the brain-actuated device to sensory areas in the brain. In this paper, we investigate the use of neural feedback to control the spatiotemporal firing patterns of neural ensembles in a model of the thalamocortical pathway. Control of pyramidal (PY) cells in the primary somatosensory cortex (S1) is achieved based on microstimulation of thalamic relay cells through multiple–input multiple–output (MIMO) feedback controllers. This closed loop feedback control mechanism is achieved by simultaneously varying the stimulation parameters ac... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312142 Sat, 01 Oct 2011 04:00:00 +0100 5312142 http://www.medworm.com/index.php?rid=5312141&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5934422 One approach to conveying tactile feedback from sensorized neural prostheses is to characterize the neural signals that would normally be produced in an intact limb and reproduce them through electrical stimulation of the residual peripheral nerves. Toward this end, we have developed an integrate-and-fire model that predicts with millisecond accuracy the timing of responses of the mechanoreceptive afferents that innervate the glabrous skin of the hand. Individual afferents produce highly repeatable and stereotyped responses to a given stimulus. However, responses differ considerably across afferents, even across afferents of a given type. In the present study, we wish to assess the extent to which this within-type variability shapes the signal conveyed by the hand to the brain. Specificall... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312141 Sat, 01 Oct 2011 04:00:00 +0100 5312141 http://www.medworm.com/index.php?rid=5312140&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5999720 A major issue to be addressed in the development of neural interfaces for prosthetic control is the need for somatosensory feedback. Here, we investigate two possible strategies: electrical stimulation of either dorsal root ganglia (DRG) or primary somatosensory cortex (S1). In each approach, we must determine a model that reflects the representation of limb state in terms of neural discharge. This model can then be used to design stimuli that artificially activate the nervous system to convey information about limb state to the subject. Electrically activating DRG neurons using naturalistic stimulus patterns, modeled on recordings made during passive limb movement, evoked activity in S1 that was similar to that of the original movement. We also found that S1 neural populations could accur... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312140 Sat, 01 Oct 2011 04:00:00 +0100 5312140 http://www.medworm.com/index.php?rid=5312139&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6035987 In this study, we used a robot-enhanced virtual environment to show that many neurons in primary somatosensory cortex with cutaneous receptive fields encode elements both of tactile contact and self-motion. We then show the results of studies examining the structure of the process which extracts the spatial location of the hand from proprioceptive signals. The structure of the spatial errors in these maps indicates that the proprioceptive-spatial map is stable but individually constructed. These seemingly disparate studies lead us to suggest that tactile sensation is encoded in a 2-D map, but one which undergoes continual dynamic modification by an underlying proprioceptive map. Understanding how the disparate signals that comprise the somatosensory system are processed to produce sensatio... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312139 Sat, 01 Oct 2011 04:00:00 +0100 5312139 http://www.medworm.com/index.php?rid=5312138&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5995170 Trans-radial amputee subjects were implanted with intrafascicular electrodes in the stumps of the median and ulnar nerves. Electrical stimulation through these electrodes was used to provide sensations of touch and finger position referred to the amputated hand. Two subjects were asked to identify different objects as to size and stiffness by manipulating them with a myo-electric hand without visual or auditory cues. Both subjects were provided with information about contact force with the objects via tactile sensations referred to their phantom hands. One subject, who was provided with information about finger position in the prosthetic hand via a different tactile sensation referred to his phantom hand, was unable to correctly identify the objects. The other subject, who received informa... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312138 Sat, 01 Oct 2011 04:00:00 +0100 5312138 http://www.medworm.com/index.php?rid=5312137&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D5776684 Intuitive somatosensory feedback is required for fine motor control. Here we explored whether thalamic electrical stimulation could provide the necessary durations and consistency of percepts for a human somatosensory neural prosthetic. Continuous and cycling high-frequency (185 Hz, 0.21 ms pulse duration charge balanced square wave) electrical pulses with the cycling patterns varying between 7% and 67% of duty cycle were applied in five patients with chronically implanted deep brain stimulators. Stimulation produced similar percepts to those elicited immediately after surgery. While consecutive continuous stimuli produced decreasing durations of sensation, the amplitude and type of percept did not change. Cycling stimulation with shorter duty cycles produced more persisting percepts. Thes... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312137 Sat, 01 Oct 2011 04:00:00 +0100 5312137 http://www.medworm.com/index.php?rid=5312136&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6033047 Intracortical microstimulation (ICMS), which has shown promise in the visual, auditory and somatosensory systems as a platform for sensory prostheses, typically relies on charged balanced, symmetric, biphasic stimulation. However, neural stimulation models as well as experiments conducted in cochlear implant users have suggested that charge balanced asymmetric pulses could generate lower detection thresholds for stimulation in terms of charge per phase. For this study, rats were chronically implanted with microelectrode arrays unilaterally in their right auditory cortex and then trained to detect ICMS delivered through a single electrode site in order to determine their behavioral threshold. This model was used in two experiments. The first experiment addressed the effect of lead phase dir... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312136 Sat, 01 Oct 2011 04:00:00 +0100 5312136 http://www.medworm.com/index.php?rid=5312135&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6025303 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312135 Sat, 01 Oct 2011 04:00:00 +0100 5312135 http://www.medworm.com/index.php?rid=5312134&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6036735 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312134 Sat, 01 Oct 2011 04:00:00 +0100 5312134 http://www.medworm.com/index.php?rid=5312133&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D6036729%26arnumber%3D6039921 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5312133 Sat, 01 Oct 2011 04:00:00 +0100 5312133 http://www.medworm.com/index.php?rid=5181042&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5977258 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181042 Sun, 31 Jul 2011 23:00:00 +0100 5181042 http://www.medworm.com/index.php?rid=5181041&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5977260 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181041 Sun, 31 Jul 2011 23:00:00 +0100 5181041 http://www.medworm.com/index.php?rid=5181040&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5977262 Cognitively challenging training sessions during robot-assisted gait training after stroke were shown to be key requirements for the success of rehabilitation. Despite a broad variability of cognitive impairments amongst the stroke population, current rehabilitation environments do not adapt to the cognitive capabilities of the patient, as cognitive load cannot be objectively assessed in real-time. We provided healthy subjects and stroke patients with a virtual task during robot-assisted gait training, which allowed modulating cognitive load by adapting the difficulty level of the task. We quantified the cognitive load of stroke patients by using psychophysiological measurements and performance data. In open-loop experiments with healthy subjects and stroke patients, we obtained training d... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181040 Sun, 31 Jul 2011 23:00:00 +0100 5181040 http://www.medworm.com/index.php?rid=5181039&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5773090 Impairments in social communication skills are thought to be core deficits in children with autism spectrum disorder (ASD). In recent years, several assistive technologies, particularly Virtual Reality (VR), have been investigated to promote social interactions in this population. It is well known that children with ASD demonstrate atypical viewing patterns during social interactions and thus monitoring eye-gaze can be valuable to design intervention strategies. While several studies have used eye-tracking technology to monitor eye-gaze for offline analysis, there exists no real-time system that can monitor eye-gaze dynamically and provide individualized feedback. Given the promise of VR-based social interaction and the usefulness of monitoring eye-gaze in real-time, a novel VR-based dynam... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181039 Sun, 31 Jul 2011 23:00:00 +0100 5181039 http://www.medworm.com/index.php?rid=5181038&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5752253 Epiretinal prostheses for the blind bypass diseased photosensitive cells in the retina, directly stimulating retinal neurons electrically and evoking signals that are relayed to the brain. Current clinical implants have few electrodes and provide limited visual acuity. Acuity may be improved by identifying electrode array design features and operational details that enhance or interfere with visual percept formation. We labeled all retinal ganglion cells in whole mount retina with a calcium reporter and then measured the number and pattern of cells responding, over a range of electrode diameters and stimulus durations. Span of the response scaled with electrode diameter for electrodes 60 $mu$m and larger. Short stimulation pulse widths selectively activated cells nearest the electrode. Our... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181038 Sun, 31 Jul 2011 23:00:00 +0100 5181038 http://www.medworm.com/index.php?rid=5181037&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5782994 The Neurochip-2 is a second generation, battery-powered device for neural recording and stimulating that is small enough to be carried in a chamber on a monkey's head. It has three recording channels, with user-adjustable gains, filters, and sampling rates, that can be optimized for recording single unit activity, local field potentials, electrocorticography, electromyography, arm acceleration, etc. Recorded data are stored on a removable, flash memory card. The Neurochip-2 also has three separate stimulation channels. Two “programmable-system-on-chips” (PSoCs) control the data acquisition and stimulus output. The PSoCs permit flexible real-time processing of the recorded data, such as digital filtering and time-amplitude window discrimination. The PSoCs can be programmed to ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181037 Sun, 31 Jul 2011 23:00:00 +0100 5181037 http://www.medworm.com/index.php?rid=5181036&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5929566 A ground reaction based method is proposed to evaluate the hypothesis that a stabilization phase occurs in transitions towards erect posture, following the macroscopic movement and preceding the quiet final erect posture, whose aim is to control and dissipate the residual inertial unbalancing forces occurring at the transition end. The experimental protocol considers three tasks leading to the final erect posture: taking a step forward (F), sit-to-stand (S), and bending the trunk forward (B), The method mainly consists of the fitting of a negative exponential function on the instability time profile following the end of the transition movement. The model parameters $Y_{0}$, $T$, and $Y_{rm inf}$, respectively, quantify the initial instability rate, a time duration related to the stabilizat... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181036 Sun, 31 Jul 2011 23:00:00 +0100 5181036 http://www.medworm.com/index.php?rid=5181035&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5929567 Lower-limb amputees expend more energy to walk than non-amputees and have an elevated risk of secondary disabilities. Insufficient push-off by the prosthetic foot may be a contributing factor. We aimed to systematically study the effect of prosthetic foot mechanics on gait, to gain insight into fundamental prosthetic design principles. We varied a single parameter in isolation, the energy-storing spring in a prototype prosthetic foot, the controlled energy storage and return (CESR) foot, and observed the effect on gait. Subjects walked on the CESR foot with three different springs. We performed parallel studies on amputees and on non-amputees wearing prosthetic simulators. In both groups, spring characteristics similarly affected ankle and body center-of-mass (COM) mechanics and metabolic ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181035 Sun, 31 Jul 2011 23:00:00 +0100 5181035 http://www.medworm.com/index.php?rid=5181034&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5929565 This paper examines the usefulness of psychophysiological measurements in a biocooperative feedback loop that adjusts the difficulty of an upper extremity rehabilitation task. Psychophysiological measurements (heart rate, skin conductance, respiration, and skin temperature) were used both by themselves and in combination with task performance and biomechanics. Data fusion was performed with discriminant analysis, and a special adaptive version was implemented that can gradually adapt to a subject. Both healthy subjects and hemiparetic patients participated in the study. The accuracy of the biocooperative controller was defined as the percentage of times it matched the subjects' preferences. The highest accuracy rate was obtained for task performance (approximately 82% for both healthy subj... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181034 Sun, 31 Jul 2011 23:00:00 +0100 5181034 http://www.medworm.com/index.php?rid=5181033&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5778990 Stroke patients often have flexor hypertonia and finger extensor weakness, which makes it difficult to open their affected hand for functional grasp. Because of this impairment, hand rehabilitation after stroke is essential for restoring functional independent lifestyles. The goal of this study is to develop a passive, lightweight, wearable device to assist with hand function during performance of activities of daily living. The device, Hand Spring Operated Movement Enhancer (HandSOME), assists with opening the patient's hand using a series of elastic cords that apply extension torques to the finger joints and compensates for the flexor hypertonia. Device design and calibration are described as well as functional and usability testing with stroke subjects with a wide range of hand impairme... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181033 Sun, 31 Jul 2011 23:00:00 +0100 5181033 http://www.medworm.com/index.php?rid=5181032&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5752250 In this study, a robotic balance system incorporating a Stewart platform base was developed to provide a new technique to investigate the neural mechanisms involved in standing balance. The robotic system, programmed with the mechanics of an inverted pendulum, controlled the motion of the body in response to a change in applied ankle torque. The ability of the robotic system to replicate the load properties of standing was validated by comparing the load stiffness generated when subjects balanced their own body to the robot's mechanical load programmed with a low (concentrated-mass model) or high (distributed-mass model) inertia. The results show that static load stiffness was not significantly $(p>0.05)$ different for standing and the robotic system. Dynamic load stiffness for the robotic... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181032 Sun, 31 Jul 2011 23:00:00 +0100 5181032 http://www.medworm.com/index.php?rid=5181031&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5752251 We have developed a mobile instrument for motion instruction and correction (MIMIC) that enables an expert (i.e., physical therapist) to map his/her movements to a trainee (i.e., patient) in a hands-free fashion. MIMIC comprises an expert module (EM) and a trainee module (TM). Both the EM and TM are composed of six-degree-of-freedom inertial measurement units, microcontrollers, and batteries. The TM also has an array of actuators that provide the user with vibrotactile instructional cues. The expert wears the EM, and his/her relevant body position is computed by an algorithm based on an extended Kalman filter that provides asymptotic state estimation. The captured expert body motion information is transmitted wirelessly to the trainee, and based on the computed difference between the exper... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181031 Sun, 31 Jul 2011 23:00:00 +0100 5181031 http://www.medworm.com/index.php?rid=5181030&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5716679 A novel method is introduced to determine asymmetry, the lateralization of brain activity, using extension of the algorithm empirical mode decomposition (EMD). The localized and adaptive nature of EMD make it highly suitable for estimating amplitude information across frequency for nonlinear and nonstationary data. Analysis illustrates how bivariate extension of EMD (BEMD) facilitates enhanced spectrum estimation for multichannel recordings that contain similar signal components, a realistic assumption in electroencephalography (EEG). It is shown how this property can be used to obtain a more accurate estimate of the marginalized spectrum, critical for the localized calculation of amplitude asymmetry in frequency. Simulations on synthetic data sets and feature estimation for a brain&#x2013... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181030 Sun, 31 Jul 2011 23:00:00 +0100 5181030 http://www.medworm.com/index.php?rid=5181029&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5773498 Differential operator has long been used in image and signal processing with great success to detect significant changes. In this paper we show that differentiation can enhance certain features of brain electrophysiological signals, contaminated with noise, artifacts, and acquisition defects, leading to efficient detection of those changes. Windowed variance method has been very successful in detecting seizure onset in the brain electrophysiological signals. In this paper we have combined these two powerful methods under the name of differential windowed variance (DWV) algorithm to automatically detect seizure onsets in almost real time, in continuous ECoG (depth-EEG) signals of epileptic patients. The main advantages of the method are simplicity of implementation and speed. We have tested... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181029 Sun, 31 Jul 2011 23:00:00 +0100 5181029 http://www.medworm.com/index.php?rid=5181028&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5776685 In order to harness the computational capacity of dissociated cultured neuronal networks, it is necessary to understand neuronal dynamics and connectivity on a mesoscopic scale. To this end, this paper uncovers dynamic spatiotemporal patterns emerging from electrically stimulated neuronal cultures using hidden Markov models (HMMs) to characterize multi-channel spike trains as a progression of patterns of underlying states of neuronal activity. However, experimentation aimed at optimal choice of parameters for such models is essential and results are reported in detail. Results derived from ensemble neuronal data revealed highly repeatable patterns of state transitions in the order of milliseconds in response to probing stimuli. (Source: IEE Transactions on Neural Systems and Rehabilitation... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181028 Sun, 31 Jul 2011 23:00:00 +0100 5181028 http://www.medworm.com/index.php?rid=5181027&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5898424 Neuroprostheses based on electrical stimulation could potentially help disabled persons. They are based on neural interface that aim at creating an intimate contact with neural cells. The efficacy of neuroprostheses can be improved by increasing the selectivity of the neural interfaces used to stimulate specific subsets of cells. Selectivity is strongly influenced by interface design. Computer models can be useful for exploring the high dimensional space of design parameters with the aim to provide guidelines for the development of more efficient electrodes, with minimal animal use and optimization of manufacturing processes. The purpose of this study was to implement a realistic model of the performance of a transverse intrafascicular multichannel electrode (TIME) implanted into the rat s... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181027 Sun, 31 Jul 2011 23:00:00 +0100 5181027 http://www.medworm.com/index.php?rid=5181026&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5977261 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181026 Sun, 31 Jul 2011 23:00:00 +0100 5181026 http://www.medworm.com/index.php?rid=5181025&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5977257%26arnumber%3D5977259 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=5181025 Sun, 31 Jul 2011 23:00:00 +0100 5181025 http://www.medworm.com/index.php?rid=4911175&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5784415 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911175 Tue, 31 May 2011 23:00:00 +0100 4911175 http://www.medworm.com/index.php?rid=4911174&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5784416 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911174 Tue, 31 May 2011 23:00:00 +0100 4911174 http://www.medworm.com/index.php?rid=4911173&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5725193 Although asynchronous intrafascicular multi-electrode stimulation (IFMS) can evoke fatigue-resistant muscle force, a priori determination of the necessary stimulation parameters for precise force production is not possible. This paper presents a proportionally-modulated, multiple-input single-output (MISO) controller that was designed and experimentally validated for real-time, closed-loop force-feedback control of asynchronous IFMS. Experiments were conducted on anesthetized felines with a Utah Slanted Electrode Array implanted in the sciatic nerve, either acutely or chronically ($n = 1$ for each). Isometric forces were evoked in plantar-flexor muscles, and target forces consisted of up to 7 min of step, sinusoidal, and more complex time-varying trajectories. The controller was successful... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911173 Tue, 31 May 2011 23:00:00 +0100 4911173 http://www.medworm.com/index.php?rid=4911172&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5722039 We report a novel behavioral paradigm which delivers microstimulation in real-time based on a rat's movements and show that rats can perform sensorimotor integration with electrically delivered stimuli. Using a real-time whisker tracking system, we delivered microstimulation in barrel cortex of actively whisking rats when their whisker crossed a particular spatial location which defined the target. Rats learned to integrate microstimulation cues with their knowledge of whisker position to infer target location along the rostro-caudal axis in less than 200 ms. In a separate experiment, we found that rats trained to respond to cortical microstimulation responded similarly to whisker deflections while ignoring auditory distracters, suggesting that barrel cortex stimulation may be perceptually... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911172 Tue, 31 May 2011 23:00:00 +0100 4911172 http://www.medworm.com/index.php?rid=4911171&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5705581 Cortical neural prostheses require chronically implanted small-area microelectrode arrays that simultaneously record and stimulate neural activity. It is necessary to develop new materials with low interface impedance and large charge transfer capacity for this application and we explore the use of conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) for the same. We subjected PEDOT coated electrodes to voltage cycling between $-$0.6 and 0.8 V, 24 h continuous biphasic stimulation at 3 ${rm mC/cm}^{2}$ and accelerated aging for four weeks. Characterization was performed using cyclic voltammetry, electrochemical impedance spectroscopy, and voltage transient measurements. We found that PEDOT coated electrodes showed a charge injection limit 15 times higher than Platinum Iridium (PtIr)... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911171 Tue, 31 May 2011 23:00:00 +0100 4911171 http://www.medworm.com/index.php?rid=4911170&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5784420 It has been shown that people can learn to perform a variety of motor tasks in novel dynamic environments without visual feedback, highlighting the importance of proprioceptive feedback in motor learning. However, our results show that it is possible to learn a viscous curl force field without proprioceptive error to drive adaptation, by providing visual information about the position error. Subjects performed reaching movements in a constraining channel created by a robotic interface. The force that subjects applied against the haptic channel was used to predict the unconstrained hand trajectory under a viscous curl force field. This trajectory was provided as visual feedback to the subjects during movement (virtual dynamics). Subjects were able to use this visual information (discrepant ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911170 Tue, 31 May 2011 23:00:00 +0100 4911170 http://www.medworm.com/index.php?rid=4911169&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5784419 Slow gait speed and interlimb asymmetry are prevalent in a variety of disorders. Current approaches to locomotor retraining emphasize the need for appropriate feedback during intensive, task-specific practice. This paper describes the design and feasibility testing of the integrated virtual environment rehabilitation treadmill (IVERT) system intended to provide real-time, intuitive feedback regarding gait speed and asymmetry during training. The IVERT system integrates an instrumented, split-belt treadmill with a front-projection, immersive virtual environment. The novel adaptive control system uses only ground reaction force data from the treadmill to continuously update the speeds of the two treadmill belts independently, as well as to control the speed and heading in the virtual environ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911169 Tue, 31 May 2011 23:00:00 +0100 4911169 http://www.medworm.com/index.php?rid=4911168&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5713843 We have developed a prototype device for take-home use that can be used in the treatment of amblyopia. The therapeutic scenario we envision involves patients first visiting a clinic, where their vision parameters are assessed and suitable parameters are determined for therapy. Patients then proceed with the actual therapeutic treatment on their own, using our device, which consists of an Apple iPod Touch running a specially modified game application. Our rationale for choosing to develop the prototype around a game stems from multiple requirements that such an application satisfies. First, system operation must be sufficiently straightforward that ease-of-use is not an obstacle. Second, the application itself should be compelling and motivate use more so than a traditional therapeutic task... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911168 Tue, 31 May 2011 23:00:00 +0100 4911168 http://www.medworm.com/index.php?rid=4911167&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5712214 Mobility is a causal factor in development. Children with mobility impairments may rely upon power mobility for independence and thus require advanced driving skills to function independently. Our previous studies show that while infants can learn to drive directly to a goal using conventional joysticks in several months of training, they are unable in this timeframe to acquire the advanced skill to avoid obstacles while driving. Without adequate driving training, children are unable to explore the environment safely, the consequences of which may in turn increase their risk for developmental delay. The goal of this research therefore is to train children seated on mobile robots to purposefully and safely drive indoors. In this paper, we present results where ten typically-developing toddl... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911167 Tue, 31 May 2011 23:00:00 +0100 4911167 http://www.medworm.com/index.php?rid=4911166&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5704586 A real-time pattern recognition algorithm based on k-nearest neighbors and lazy learning was used to classify, voluntary electromyography (EMG) signals and to simultaneously control movements of a dexterous artificial hand. EMG signals were superficially recorded by eight pairs of electrodes from the stumps of five transradial amputees and forearms of five able-bodied participants and used online to control a robot hand. Seven finger movements (not involving the wrist) were investigated in this study. The first objective was to understand whether and to which extent it is possible to control continuously and in real-time, the finger postures of a prosthetic hand, using superficial EMG, and a practical classifier, also taking advantage of the direct visual feedback of the moving hand. The s... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911166 Tue, 31 May 2011 23:00:00 +0100 4911166 http://www.medworm.com/index.php?rid=4911165&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5710985 In this study, we propose a more complex signal model that includes the variability in amplitude of each unit potential. Moreover, we propose the Markov Chain Monte Carlo (MCMC) simulation and a Bayesian minimum mean square error (MMSE) estimator by averaging on samples that converge in distribution to the joint posterior law. We prove the convergence property of this approach mathematically and we test the method representatively on intramuscular multiunit recordings. The results showed that its average accuracy in spike identification is greater than 90% for intramuscular signals with up to 8 concurrently active units. In addition to intramuscular signals, the method can be applied for spike sorting of other types of multiunit recordings. (Source: IEE Transactions on Neural Systems and R... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911165 Tue, 31 May 2011 23:00:00 +0100 4911165 http://www.medworm.com/index.php?rid=4911164&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5692835 This paper introduces a novel technique to address the instability and time variability challenges associated with brain activity recorded on different days. A critical challenge when working with brain signal activity is the variability in their characteristics when the signals are collected in different sessions separated by a day or more. Such variability is due to the acute and chronic responses of the brain tissue after implantation, variations as the subject learns to optimize performance, physiological changes in a subject due to prior activity or rest periods and environmental conditions. We propose a novel approach to tackle signal variability by focusing on learning subspaces which are recurrent over time. Furthermore, we illustrate how we can use projections on those subspaces t... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911164 Tue, 31 May 2011 23:00:00 +0100 4911164 http://www.medworm.com/index.php?rid=4911163&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5733429 This study is a successor of our previous study (BCI demographics I) and examines correlations among BCI performance, personal preferences, and different subject factors such as age or gender for two sets of steady-state visual evoked potential (SSVEP) stimuli: one in the medium frequency range (13, 14, 15 and 16 Hz) and another in the high-frequency range (34, 36, 38, 40 Hz). High-frequency SSVEPs (above 30 Hz) diminish user fatigue and risk of photosensitive epileptic seizures. Results showed that most people, despite having no prior BCI experience, could use the SSVEP-based Bremen-BCI system in a very noisy field setting at a fair. Results showed that demographic parameters as well as handedness, tiredness, alcohol and caffeine consumption, etc., have no significant effect on the perfor... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911163 Tue, 31 May 2011 23:00:00 +0100 4911163 http://www.medworm.com/index.php?rid=4911162&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5716680 In this paper, we propose a clustering linear discriminant analysis algorithm (CLDA) to accurately decode hand movement directions from a small number of training trials for magnetoencephalography-based brain computer interfaces (BCIs). CLDA first applies a spectral clustering algorithm to automatically partition the BCI features into several groups where the within-group correlation is maximized and the between-group correlation is minimized. As such, the covariance matrix of all features can be approximated as a block diagonal matrix, thereby facilitating us to accurately extract the correlation information required by movement decoding from a small set of training data. The efficiency of the proposed CLDA algorithm is theoretically studied and an error bound is derived. Our experiment o... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911162 Tue, 31 May 2011 23:00:00 +0100 4911162 http://www.medworm.com/index.php?rid=4911161&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5784417 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911161 Tue, 31 May 2011 23:00:00 +0100 4911161 http://www.medworm.com/index.php?rid=4911160&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5784414%26arnumber%3D5784418 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4911160 Tue, 31 May 2011 23:00:00 +0100 4911160 http://www.medworm.com/index.php?rid=4733563&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5745719 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733563 Thu, 31 Mar 2011 23:00:00 +0100 4733563 http://www.medworm.com/index.php?rid=4733562&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5745721 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733562 Thu, 31 Mar 2011 23:00:00 +0100 4733562 http://www.medworm.com/index.php?rid=4733561&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5676231 The lack of proprioceptive feedback is a serious deficiency of current prosthetic control systems. The Osseo-Magnetic Link (OML) is a novel humeral or wrist rotation control system that could preserve proprioception. It utilizes a magnet implanted within the residual bone and sensors mounted in the prosthetic socket to detect magnetic field vectors and determine the bone's orientation. This allows the use of volitional bone rotation to control a prosthetic rotator. We evaluated the performance of the OML using a physical model of a transhumeral residual limb. A small Neodymium-Iron-Boron magnet was placed in a model humerus, inside a model upper arm. Four three-axis Hall-effect sensors were mounted on a ring 3 cm distal to the magnet. An optimization algorithm based on Newton's method dete... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733561 Thu, 31 Mar 2011 23:00:00 +0100 4733561 http://www.medworm.com/index.php?rid=4733560&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5664798 Next-generation neuroprosthetic limbs will require a reliable long-term neural interface to residual nerves in the peripheral nervous system (PNS). To this end, we have developed novel biocompatible materials and a fabrication technique to create high site-count microelectrodes for stimulating and recording from regenerated peripheral nerves. Our electrodes are based on a biodegradable tyrosine-derived polycarbonate polymer system with suitable degradation and erosion properties and a fabrication technique for deployment of the polymer in a porous, degradable, regenerative, multiluminal, multielectrode conduit. The in vitro properties of the polymer and the electrode were tuned to retain mechanical strength for over 24 days and to completely degrade and erode within 220 days. The fabricati... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733560 Thu, 31 Mar 2011 23:00:00 +0100 4733560 http://www.medworm.com/index.php?rid=4733559&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5703131 This study suggests that signals from a small ensemble of motor cortical neurons $({sim}40)$ can be used for natural point-and-click 2-D cursor control of a personal computer. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733559 Thu, 31 Mar 2011 23:00:00 +0100 4733559 http://www.medworm.com/index.php?rid=4733558&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5676233 Pattern recognition–based control of myoelectric prostheses has shown great promise in research environments, but has not been optimized for use in a clinical setting. To explore the relationship between classification error, controller delay, and real-time controllability, 13 able-bodied subjects were trained to operate a virtual upper-limb prosthesis using pattern recognition of electromyogram (EMG) signals. Classification error and controller delay were varied by training different classifiers with a variety of analysis window lengths ranging from 50 to 550 ms and either two or four EMG input channels. Offline analysis showed that classification error decreased with longer window lengths ( ${ p} < 0.01$). Real-time controllability was evaluated with the target achievement cont... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733558 Thu, 31 Mar 2011 23:00:00 +0100 4733558 http://www.medworm.com/index.php?rid=4733557&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5628272 This paper presents an algorithm to perform online tremor characterization from motion sensors measurements, while filtering the voluntary motion performed by the patient. In order to estimate simultaneously both nonstationary signals in a stochastic filtering framework, pathological tremor was represented by a time-varying harmonic model and voluntary motion was modeled as an auto-regressive moving-average (ARMA) model. Since it is a nonlinear problem, an extended Kalman filter (EKF) was used. The developed solution was evaluated with simulated signals and experimental data from patients with different pathologies. Also, the results were comprehensively compared with alternative techniques proposed in the literature, evidencing the better performance of the proposed method. The algorithm ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733557 Thu, 31 Mar 2011 23:00:00 +0100 4733557 http://www.medworm.com/index.php?rid=4733556&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5625915 In conclusion, the viscosity of model 1 would be appropriate for quantification of clinical ratings of rigidity and that of model 2 for distinction of PD and also for investigation of phase-dependent characteristics in parkinsonian rigidity. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733556 Thu, 31 Mar 2011 23:00:00 +0100 4733556 http://www.medworm.com/index.php?rid=4733555&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5608506 In this paper a novel electrically actuated parallel robot with three degrees-of-freedom (3 DOF) for dynamic postural studies is presented. The design has been described, the solution to the inverse kinematics has been found, and a numerical solution for the direct kinematics has been proposed. The workspace of the implemented robot is characterized by an angular range of motion of about ${pm}10^{circ}$ for roll and pitch when yaw is in the range ${pm}15^{circ}$. The robot was constructed and the orientation accuracy was tested by means of an optoelectronic system and by imposing a sinusoidal input, with a frequency of 1 Hz and amplitude of 10$^{circ}$, along the three axes, in sequence. The collected data indicated a phase delay of 1$^{circ}$ and an amplitude error of 0.5%–1.5%; si... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733555 Thu, 31 Mar 2011 23:00:00 +0100 4733555 http://www.medworm.com/index.php?rid=4733554&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5625916 The task of discriminating the neural pathways responsible for the activity recorded using a multi-contact nerve cuff electrode has recently been approached as an inverse problem of source localization, similar to EEG source localization. A major drawback of this method is that it requires a model of the nerve, and that the localization performance is highly dependent on the accuracy of this model. Using recordings from a 56-contact “matrix” cuff electrode placed on a rat sciatic nerve, we investigated a method that eliminates the need for a model, and uses instead an “experimental” leadfield constructed from a training set of experimental recordings. The resulting pathway-identification task is solved using an inverse problem framework. The experimental leadfie... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733554 Thu, 31 Mar 2011 23:00:00 +0100 4733554 http://www.medworm.com/index.php?rid=4733553&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5585776 This paper reported initial findings on the effects of environmental noise and auditory distractions on the performance of mental state classification based on near-infrared spectroscopy (NIRS) signals recorded from the prefrontal cortex. Characterization of the performance losses due to environmental factors could provide useful information for the future development of NIRS-based brain-computer interfaces that can be taken beyond controlled laboratory settings and into everyday environments. Experiments with a hidden Markov model-based classifier showed that while significant performance could be attained in silent conditions, only chance levels of sensitivity and specificity were obtained in noisy environments. In order to achieve robustness against environment noise, two strategies wer... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733553 Thu, 31 Mar 2011 23:00:00 +0100 4733553 http://www.medworm.com/index.php?rid=4733552&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5599306 The ability to accurately infer functional connectivity between ensemble neurons using experimentally acquired spike train data is currently an important research objective in computational neuroscience. Point process generalized linear models and maximum likelihood estimation have been proposed as effective methods for the identification of spiking dependency between neurons. However, unfavorable experimental conditions occasionally results in insufficient data collection due to factors such as low neuronal firing rates or brief recording periods, and in these cases, the standard maximum likelihood estimate becomes unreliable. The present studies compares the performance of different statistical inference procedures when applied to the estimation of functional connectivity in neuronal ass... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733552 Thu, 31 Mar 2011 23:00:00 +0100 4733552 http://www.medworm.com/index.php?rid=4733551&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5664799 Increasing concentrations of anesthetics in the blood induce a continuum of neurophysiological changes, which reflect on the electroencephalogram (EEG). EEG-based depth of anesthesia assessment requires that the signal samples are correctly associated with the neurophysiological changes occurring at different anesthetic levels. A novel method is presented to estimate the phase of the continuum using the feature data extracted from EEG. The feature data calculated from EEG sequences corresponding to continuously deepening anesthesia are considered to form a one-dimensional nonlinear manifold in the multidimensional feature space. Utilizing a recently proposed algorithm, Isomap, the dimensionality of the feature data is reduced to achieve a one-dimensional embedding representing this manifol... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733551 Thu, 31 Mar 2011 23:00:00 +0100 4733551 http://www.medworm.com/index.php?rid=4733550&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5745720 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733550 Thu, 31 Mar 2011 23:00:00 +0100 4733550 http://www.medworm.com/index.php?rid=4733549&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5745718%26arnumber%3D5746486 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4733549 Thu, 31 Mar 2011 23:00:00 +0100 4733549 http://www.medworm.com/index.php?rid=4445554&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5710487 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445554 Tue, 01 Feb 2011 00:00:00 +0100 4445554 http://www.medworm.com/index.php?rid=4445553&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5710489 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445553 Tue, 01 Feb 2011 00:00:00 +0100 4445553 http://www.medworm.com/index.php?rid=4445552&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5710509 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445552 Tue, 01 Feb 2011 00:00:00 +0100 4445552 http://www.medworm.com/index.php?rid=4445551&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5559477 This paper proposes an advanced robust multivariable control strategy for a powered wheelchair system. The new control strategy is based on a combination of the systematic triangularization technique and the robust neuro-sliding mode control approach. This strategy effectively copes with parameter uncertainties and external disturbances in real-time in order to achieve robustness and optimal performance of a multivariable system. This novel strategy reduces coupling effects on a multivariable system, eliminates chattering phenomena, and avoids the plant Jacobian calculation problem. Furthermore, the strategy can also achieve fast and global convergence using less computation. The effectiveness of the new multivariable control strategy is verified in real-time implementation on a powered wh... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445551 Tue, 01 Feb 2011 00:00:00 +0100 4445551 http://www.medworm.com/index.php?rid=4445550&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5559478 A new auditory orientation training system was developed for blind people using acoustic virtual reality (VR) based on a head-related transfer function (HRTF) simulation. The present training system can reproduce a virtual training environment for orientation and mobility (O&M) instruction, and the trainee can walk through the virtual training environment safely by listening to sounds such as vehicles, stores, ambient noise, etc., three-dimensionally through headphones. The system can reproduce not only sound sources but also sound reflection and insulation, so that the trainee can learn both sound location and obstacle perception skills. The virtual training environment is described in extensible markup language (XML), and the O&M instructor can edit it easily according to the tra... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445550 Tue, 01 Feb 2011 00:00:00 +0100 4445550 http://www.medworm.com/index.php?rid=4445549&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5560867 An implantable prosthesis that stimulates vestibular nerve branches to restore sensation of head rotation and vision-stabilizing reflexes could benefit individuals disabled by bilateral loss of vestibular (inner ear balance) function. We developed a prosthesis that partly restores normal function in animals by delivering pulse frequency modulated (PFM) biphasic current pulses via electrodes implanted in semicircular canals. Because the optimal stimulus encoding strategy is not yet known, we investigated effects of varying biphasic current pulse frequency, amplitude, duration, and interphase gap on vestibulo-ocular reflex (VOR) eye movements in chinchillas. Increasing pulse frequency increased response amplitude while maintaining a relatively constant axis of rotation. Increasing pulse ampl... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445549 Tue, 01 Feb 2011 00:00:00 +0100 4445549 http://www.medworm.com/index.php?rid=4445548&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5560868 Intraspinal microstimulation (ISMS) employs electrical stimulation of the ventral grey matter to reactivate paralyzed skeletal muscle. This work evaluated the transformations in the quadriceps muscle that occurred following complete transection and chronic stimulation with ISMS or a standard nerve cuff (NCS). Stimulation was applied for 30 days, 4 h/day. Both methods induced significant increases in time-to-peak tension (ISMS 35%, NCS 25%) and half rise-time (ISMS 39%, NCS 25%) compared to intact controls (IC). Corresponding increases in type-IIA myosin heavy chain (MHC) and decreases in type-IID MHC were noted compared to IC. These results were unexpected because ISMS recruits motor units in a near-normal physiological order while NCS recruits motor units in a reversed order. Spinal cord ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445548 Tue, 01 Feb 2011 00:00:00 +0100 4445548 http://www.medworm.com/index.php?rid=4445547&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5604320 This paper extends a previously developed level- ground walking control methodology to enable an above knee amputee to walk up slopes using a powered knee and ankle prosthesis. Experimental results corresponding to walking on level ground and two different slope angles (5 $^circ$ and 10 $^circ$) with the powered prosthesis using the control method are compared to walking under the same conditions with a passive prosthesis. The data indicate that the powered prosthesis with the upslope walking controller is able to reproduce several kinematic characteristics of healthy upslope walking that the passive prosthesis does not (such as knee flexion after heel strike and a powered ankle plantarflexion during push-off). Finally, results are shown that demonstrate the ability of the prosthesis to ge... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445547 Tue, 01 Feb 2011 00:00:00 +0100 4445547 http://www.medworm.com/index.php?rid=4445546&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5475227 The objective of the work is to optimize the design of spring-loaded crutches by choosing appropriate spring stiffness based on their dynamic characteristics. It was shown in the literature that ambulation with spring-loaded crutches reduces the initial impulse yielded by ambulation with standard crutches and provides a propulsion mechanism. This research not only provides a genre of the spring-loaded crutches via compliance, but also proposes an approach to optimize the stiffness of the helical spring through studying the dynamics of crutch stance. The method is developed using a boundary value problem and its solution method and is studied numerically. Experiments were carried out on four subjects in a biomechanics laboratory. It suggests that the optimized spring-loaded crutches guarant... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445546 Tue, 01 Feb 2011 00:00:00 +0100 4445546 http://www.medworm.com/index.php?rid=4445545&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5510188 If electromyography (EMG) decomposition is to be a useful tool for scientific investigation, it is essential to know that the results are accurate. Because of background noise, waveform variability, motor-unit action potential (MUAP) indistinguishability, and perplexing superpositions, accuracy assessment is not straightforward. This paper presents a rigorous statistical method for assessing decomposition accuracy based only on evidence from the signal itself. The method uses statistical decision theory in a Bayesian framework to integrate all the shape- and firing-time-related information in the signal to compute an objective a posteriori measure of confidence in the accuracy of each discharge in the decomposition. The assessment is based on the estimated statistical properties of the MUA... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445545 Tue, 01 Feb 2011 00:00:00 +0100 4445545 http://www.medworm.com/index.php?rid=4445544&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5585827 An implantable stimulator-telemeter (IST-12) was developed for applications in neuroprosthetic restoration of limb function in paralyzed individuals. The IST-12 provides 12 stimulation channels and two myoelectric signal (MES) channels. The MES circuitry includes a two-channel multiplexer, preamplifier, variable gain amplifier/bandpass filter, full-wave rectifier, and bin integrator. Power and control signals are transmitted from an external control unit to the IST-12 through an inductive link. Recorded MES signals are telemetered back to the external control unit through the same inductive link. Following bench testing, one device was implanted chronically in a dog for 15 months and evaluated. Conditions were identified in which MES could be recorded with minimal stimulus artifact. The ab... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445544 Tue, 01 Feb 2011 00:00:00 +0100 4445544 http://www.medworm.com/index.php?rid=4445543&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5560866 Two of the most critical tasks when designing a portable wireless neural recording system are to limit power consumption and to efficiently use the limited bandwidth. It is known that for most wireless devices the majority of power is consumed by the wireless transmitter and it often represents the bottleneck of the overall design. This paper compares two compression techniques that take advantage of the sparseness of the neural spikes in neural recordings using an information theoretic formalism to enhance the well-established vector quantization (VQ) algorithm. The two discriminative VQ algorithms are applied to neuronal recordings proving their ability to accurately reconstruct action potential (AP) regions of the neuronal signal while compressing background activity without using thres... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445543 Tue, 01 Feb 2011 00:00:00 +0100 4445543 http://www.medworm.com/index.php?rid=4445542&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5638150 The Kalman filter is commonly used in neural interface systems to decode neural activity and estimate the desired movement kinematics. We analyze a low-complexity Kalman filter implementation in which the filter gain is approximated by its steady-state form, computed offline before real-time decoding commences. We evaluate its performance using human motor cortical spike train data obtained from an intracortical recording array as part of an ongoing pilot clinical trial. We demonstrate that the standard Kalman filter gain converges to within 95% of the steady-state filter gain in $1.5pm 0.5~{rm s}~({rm mean} pm {rm s.d.})$. The difference in the intended movement velocity decoded by the two filters vanishes within 5 s, with a correlation coefficient of 0.99 between the two decoded velociti... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445542 Tue, 01 Feb 2011 00:00:00 +0100 4445542 http://www.medworm.com/index.php?rid=4445541&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5590300 The objective of this work was to develop a closed-loop control system that automatically adjusted the stimulation amplitude to reduce oscillatory neuronal activity, based on feedback of electrical signals recorded from the brain using the same electrode as implanted for stimulation. We simulated a population of 100 intrinsically active model neurons in the Vim thalamus, and the local field potentials (LFPs) generated by the population were used as the feedback (control) variable for closed loop control of DBS amplitude. Based on the correlation between the spectral content of the thalamic activity and tremor (Hua , 1998), (Lenz , 1988), we implemented an adaptive minimum variance controller to regulate the power spectrum of the simulated LFPs and restore the LFP power spectrum present und... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445541 Tue, 01 Feb 2011 00:00:00 +0100 4445541 http://www.medworm.com/index.php?rid=4445540&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5460913 In this study, we proposed modifications both to the interface and to the classification system, in order to reduce the number of required stimulus repetitions and consequently boost the information transfer rate. We initially incorporated a custom-built dictionary into the classification system, and conducted a study on 14 healthy subjects who copy-spelled 15 four letter words. Incorporating the dictionary, the mean accuracy at five trials increased from 72.86% to 95.71%. To further increase the system performance, we first validated the hypothesis that for a conventional P300 system, most target-error pairs lie on the same row or column. Then based on the validated hypothesis, we adjusted letter positions on the well-known from A to Z interface. The same subjects spelled the same 15 word... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445540 Tue, 01 Feb 2011 00:00:00 +0100 4445540 http://www.medworm.com/index.php?rid=4445539&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5582300 In this study, we demonstrate a BCI system for orthosis control. Our BCI was asynchronous, meaning that subjects could move the orthosis whenever they wanted, instead of pacing themselves to external cues. Seven subjects each performed two tasks with a BCI that relied on steady state visual evoked potentials (SSVEPs). Although none of the subjects had any training, six subjects showed good control with a positive predictive value (PPV) higher than 60%. The overall PPV for all subjects reached $78hbox{%} pm 10hbox{%}$. However, the false positive rate was high, and some subjects dislike the flickering lights required in SSVEP BCIs. In follow-up work, we hope to reduce both the false positive rate and the annoyance produced by flickering lights by hybridizing this BCI with a “brain sw... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445539 Tue, 01 Feb 2011 00:00:00 +0100 4445539 http://www.medworm.com/index.php?rid=4445538&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5710488 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445538 Tue, 01 Feb 2011 00:00:00 +0100 4445538 http://www.medworm.com/index.php?rid=4445537&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5710486%26arnumber%3D5710541 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4445537 Tue, 01 Feb 2011 00:00:00 +0100 4445537 http://www.medworm.com/index.php?rid=4298517&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5672640 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4298517 Wed, 01 Dec 2010 00:00:00 +0100 4298517 http://www.medworm.com/index.php?rid=4258546&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5658923 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258546 Wed, 01 Dec 2010 00:00:00 +0100 4258546 http://www.medworm.com/index.php?rid=4258545&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5658922 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258545 Wed, 01 Dec 2010 00:00:00 +0100 4258545 http://www.medworm.com/index.php?rid=4258544&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5658920 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258544 Wed, 01 Dec 2010 00:00:00 +0100 4258544 http://www.medworm.com/index.php?rid=4258543&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5658918 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258543 Wed, 01 Dec 2010 00:00:00 +0100 4258543 http://www.medworm.com/index.php?rid=4258542&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5560864 This study has implications for nerve block electrode and stimulation parameter selection for clinical therapy systems and basic neurophysiology studies. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258542 Wed, 01 Dec 2010 00:00:00 +0100 4258542 http://www.medworm.com/index.php?rid=4258541&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5594648 In conclusion, comprehensive joint feedback demonstrates potential to markedly improve FNS standing function. However, alternative control structures capable of effective performance with fewer sensor-based feedback parameters may better facilitate clinical usage. (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258541 Wed, 01 Dec 2010 00:00:00 +0100 4258541 http://www.medworm.com/index.php?rid=4258540&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5497186 Human lumbar spinal cord networks controlling stepping and standing can be activated through posterior root stimulation using implanted electrodes. A new stimulation method utilizing surface electrodes has been shown to excite lumbar posterior root fibers similarly as with implants, an unexpected finding considering the distance to these target neurons. In the present study we apply computer modeling to compare the depolarization of posterior root fibers by both stimulation techniques. We further examine the potential for additional direct activation of motoneurons within the anterior roots. Using an implant, action potentials are initiated in the posterior root fibers at their entry into the spinal cord or along the longitudinal portions of the fiber trajectories, depending on the cathode... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258540 Wed, 01 Dec 2010 00:00:00 +0100 4258540 http://www.medworm.com/index.php?rid=4258539&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5482074 A bioptic telescope is a visual aid used by people with impaired vision when driving in many U.S. states, though bioptic driving remains controversial. Objective data on how and when bioptic drivers use the telescope and what they look at with it are crucial to understanding the bioptic telescope's effects on driving. A video-based technique to track the telescope's aiming point is presented in this paper. With three infrared retro-reflective markers pasted on the bioptic spectacles frame, its movement is recorded using an infrared camera unit with infrared LED illuminators. The angles formed by the three markers are used to calculate the telescope's aiming points, which are registered with road scene images recorded by another camera. The calculation is based on a novel one-time calibrati... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258539 Wed, 01 Dec 2010 00:00:00 +0100 4258539 http://www.medworm.com/index.php?rid=4258538&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5559476 Falls and fall related injuries are a significant cause of morbidity, disability, and health care utilization, particularly among the age group of 65 years and over. The ability to detect falls events in an unsupervised manner would lead to improved prognoses for falls victims. Several wearable accelerometry and gyroscope-based falls detection devices have been described in the literature; however, they all suffer from unacceptable false positive rates. This paper investigates the augmentation of such systems with a barometric pressure sensor, as a surrogate measure of altitude, to assist in discriminating real fall events from normal activities of daily living. The acceleration and air pressure data are recorded using a wearable device attached to the subject's waist and analyzed offline.... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258538 Wed, 01 Dec 2010 00:00:00 +0100 4258538 http://www.medworm.com/index.php?rid=4258537&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5444912 The aim of this study was to determine the effects of a newly developed reciprocal gait orthosis (RGO) with a variable constraint hip mechanism (VCHM) on the kinematics and kinetics of normal gait. The VCHM was compared with the isocentric reciprocating gait orthosis (IRGO) for walking after paraplegia. Both the VCHM and the IRGO were evaluated with able-bodied volunteers with the hip reciprocating mechanisms coupled and uncoupled. The VCHM was further evaluated with context-dependent coupling based on a finite-state control algorithm utilizing information from brace-mounted sensors. Walking performance for each brace condition was also compared to normal walking without an orthosis. Without the hip controller, the VCHM affected the kinematics of the hip joint in a similar manner as the IR... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258537 Wed, 01 Dec 2010 00:00:00 +0100 4258537 http://www.medworm.com/index.php?rid=4258536&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5559475 An electroencephalographic (EEG) brain–computer interface (BCI) internet browser was designed and evaluated with 10 healthy volunteers and three individuals with advanced amyotrophic lateral sclerosis (ALS), all of whom were given tasks to execute on the internet using the browser. Participants with ALS achieved an average accuracy of 73% and a subsequent information transfer rate (ITR) of 8.6 bits/min and healthy participants with no prior BCI experience over 90% accuracy and an ITR of 14.4 bits/min. We define additional criteria for unrestricted internet access for evaluation of the presented and future internet browsers, and we provide a review of the existing browsers in the literature. The P300-based browser provides unrestricted access and enables free web surfing for individu... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258536 Wed, 01 Dec 2010 00:00:00 +0100 4258536 http://www.medworm.com/index.php?rid=4258535&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5462915 While brain–computer interfaces (BCIs) can provide communication to people who are locked-in, they suffer from a very low information transfer rate. Further, using a BCI requires a concentration effort and using it continuously can be tiring. The brain controlled wheelchair (BCW) described in this paper aims at providing mobility to BCI users despite these limitations, in a safe and efficient way. Using a slow but reliable P300 based BCI, the user selects a destination amongst a list of predefined locations. While the wheelchair moves on virtual guiding paths ensuring smooth, safe, and predictable trajectories, the user can stop the wheelchair by using a faster BCI. Experiments with nondisabled subjects demonstrated the efficiency of this strategy. Brain control was not affected whe... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258535 Wed, 01 Dec 2010 00:00:00 +0100 4258535 http://www.medworm.com/index.php?rid=4258534&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5585778 Films like Firefox, Surrogates, and Avatar have explored the possibilities of using brain–computer interfaces (BCIs) to control machines and replacement bodies with only thought. Real world BCIs have made great progress toward that end. Invasive BCIs have enabled monkeys to fully explore 3-D space using neuroprosthetics. However, noninvasive BCIs have not been able to demonstrate such mastery of 3-D space. Here, we report our work, which demonstrates that human subjects can use a noninvasive BCI to fly a virtual helicopter to any point in a 3-D world. Through use of intelligent control strategies, we have facilitated the realization of controlled flight in 3-D space. We accomplished this through a reductionist approach that assigns subject-specific control signals to the crucial com... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258534 Wed, 01 Dec 2010 00:00:00 +0100 4258534 http://www.medworm.com/index.php?rid=4258533&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5658919 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258533 Wed, 01 Dec 2010 00:00:00 +0100 4258533 http://www.medworm.com/index.php?rid=4258532&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5658599%26arnumber%3D5658921 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4258532 Wed, 01 Dec 2010 00:00:00 +0100 4258532 http://www.medworm.com/index.php?rid=4044888&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5596182 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044888 Thu, 30 Sep 2010 23:00:00 +0100 4044888 http://www.medworm.com/index.php?rid=4044887&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5596183 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044887 Thu, 30 Sep 2010 23:00:00 +0100 4044887 http://www.medworm.com/index.php?rid=4044886&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5596188 (Source: IEE Transactions on Neural Systems and Rehabilitation Engineering) IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044886 Thu, 30 Sep 2010 23:00:00 +0100 4044886 http://www.medworm.com/index.php?rid=4044885&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5510189 The paper investigates the impact of the integration of the visual error augmentation training method with the assist-as-needed training method in robot-assisted rehabilitation training of the upper extremity. A robot-assisted rehabilitation system is developed that integrates an assistive controller, which can provide robotic assistance to the participant as and when needed, with a visual error augmentation mechanism, which amplifies the tracking error to heighten the participant's motivation to improve tracking accuracy. A crossover study is designed to evaluate the impact of the integration of the visual error augmentation method with the assist-as-needed training method. Experimental results on unimpaired participants demonstrate improved performance has been achieved in the integrated... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044885 Thu, 30 Sep 2010 23:00:00 +0100 4044885 http://www.medworm.com/index.php?rid=4044884&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5446353 Visuo-spatial neglect (often simply referred to as “neglect”) is a complex poststroke medical syndrome which may be assessed by means of a series of drawing-based tests. Based on a novel analysis of a test battery formed from established pencil-and-paper tests, the aim of this study is to develop an automated assessment system which enables objectivity, repeatability, and diagnostic capability in the scoring process. Furthermore, the novel assessment system encapsulates temporal sequence and other “dynamic” information inherent in the drawing process. Several approaches are introduced in this paper and the results compared. The optimal model is shown to produce significant agreement with the score for drawing-related components of the Rivermead Behavioural Inatt... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044884 Thu, 30 Sep 2010 23:00:00 +0100 4044884 http://www.medworm.com/index.php?rid=4044883&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5445015 While a number of devices have recently been developed to facilitate hand rehabilitation after stroke, most place some restrictions on movement of the digits or arm. Thus, a novel glove was developed which can provide independent extension assistance to each digit while still allowing full arm movement. This pneumatic glove, the PneuGlove, can be used for training grasp-and-release movements either with real objects or with virtual objects in a virtual reality environment. Two groups of stroke survivors, with seven subjects in each group, completed a six-week rehabilitation training protocol, consisting of three 1-h sessions held each week. One group wore the PneuGlove during training, performed both within a novel virtual reality environment and outside of it with physical objects, while ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044883 Thu, 30 Sep 2010 23:00:00 +0100 4044883 http://www.medworm.com/index.php?rid=4044882&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5444967 We present a robust 3-D parts-based (PB) tracking system designed to follow the upper limb of stroke survivors during desktop activities. This system fits a probabilistic model of the arm to sequences of images taken from multiple angles. The arm model defines shapes and colors of limbs and limb configurations that are more or less likely. We demonstrate that the system is 1) robust to cluttered scenes and temporary occlusions, 2) accurate relative to a commercial motion capture device, and 3) capable of capturing kinematics that correlate with concurrent measures of post-stroke limb function. To evaluate the PB system, the functional motion of seven stroke survivors was measured concurrently with the PB system and a commercial motion capture system. In addition, functional motion was asse... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044882 Thu, 30 Sep 2010 23:00:00 +0100 4044882 http://www.medworm.com/index.php?rid=4044881&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5497185 This paper presents a novel mixed reality rehabilitation system used to help improve the reaching movements of people who have hemiparesis from stroke. The system provides real-time, multimodal, customizable, and adaptive feedback generated from the movement patterns of the subject's affected arm and torso during reaching to grasp. The feedback is provided via innovative visual and musical forms that present a stimulating, enriched environment in which to train the subjects and promote multimodal sensory-motor integration. A pilot study was conducted to test the system function, adaptation protocol and its feasibility for stroke rehabilitation. Three chronic stroke survivors underwent training using our system for six 75-min sessions over two weeks. After this relatively short time, all th... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044881 Thu, 30 Sep 2010 23:00:00 +0100 4044881 http://www.medworm.com/index.php?rid=4044880&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5596194 Individuals who have suffered cerebral insults often exhibit stiff-knee gait, a condition characterized by reduced knee flexion during swing. We investigated the effect that an increment in normal rectus femoris (RF) activity can have on hip and knee joint angles during swing, as a first step to determining this muscle's involvement in stiff-knee gait. For this, we developed a protocol that electrically stimulated the RF during pre-swing or after toe-off in randomly selected strides of treadmill walking, consistent with the timing of RF activity during normal gait. Seven healthy young adults participated in the study. Pre-swing stimulation induced a significant $({ p}<0.05)$ reduction in peak knee flexion (avg 7.5$^circ$ ) in all subjects, with an accompanying decrease in hip flexion in... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044880 Thu, 30 Sep 2010 23:00:00 +0100 4044880 http://www.medworm.com/index.php?rid=4044879&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5444965 For the realization of better in-home nursing environment, understanding the swallowing function and its process are quite essential to realize appropriate rehabilitation policies and dietary menus to prevent aspirations. However, the swallowing function is currently examined using mainly large-scale and expensive methods such as video fluoroscopic examination of swallowing, mesophagia fiber, palatal pressure measurement, CT, and cine MRI, which are difficult to be used at patients' homes. This paper proposes an age model, which applies a self organization map (SOM) to evaluate the swallowing function. As parameters to make the SOM, the lead time, the geniohyoid muscle, and the thyrohyid muscle are measured using photo sensors with a little invasiveness. To verify the effectiveness of our ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044879 Thu, 30 Sep 2010 23:00:00 +0100 4044879 http://www.medworm.com/index.php?rid=4044878&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5596181%26arnumber%3D5482032 The Rutgers Arm II (RA II) is a new system that trains the shoulder/arm motor control, strengthening, arm speed of motion, endurance, and grasp strength in a single rehabilitation session. The system components are a tilted low-friction table, a forearm support with markers and wireless transmitter, a shoulder appendage to detect compensatory leaning, infrared vision tracking, a large display and a PC running custom virtual reality games. Three participants in the chronic stage post-stroke were trained on the RAII for four weeks (12 sessions) and had a follow-up evaluation after three months. The results of this study indicate that the participants were able to use the technology, and preliminary results are encouraging. One participant showed improvement in all timed Jebsen–Taylor ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=4044878 Thu, 30 Sep 2010 23:00:00 +0100 4044878