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. Sun, 21 Mar 2010 17:31:18 +0100 http://www.medworm.com/index.php?rid=3334999&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5420314 (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=3334999 Mon, 01 Feb 2010 00:00:00 +0100 3334999 http://www.medworm.com/index.php?rid=3334998&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5420313 (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=3334998 Mon, 01 Feb 2010 00:00:00 +0100 3334998 http://www.medworm.com/index.php?rid=3334997&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5420311 (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=3334997 Mon, 01 Feb 2010 00:00:00 +0100 3334997 http://www.medworm.com/index.php?rid=3334996&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5378606 We have recently demonstrated in simulations and experiments that a proportional and derivative (PD) feedback controller can regulate the active ankle torque during quiet stance and stabilize the body despite a long sensory-motor time delay. The purpose of the present study was to: 1) model the active and passive ankle torque mechanisms and identify their contributions to the total ankle torque during standing and 2) investigate whether a neural-mechanical control scheme that implements the PD controller as the neural controller can successfully generate the total ankle torque as observed in healthy individuals during quiet stance. Fourteen young subjects were asked to stand still on a force platform to acquire data for model optimization and validation. During two trials of 30 s each, the... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334996 Mon, 01 Feb 2010 00:00:00 +0100 3334996 http://www.medworm.com/index.php?rid=3334995&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5196800 The aim of this study was to describe in detail a new method, called normalized force control parameter (nFCP), to measure changes in movement dynamics obtained during robot-aided neurorehabilitation, and to evaluate its ability to estimate the clinical scales. The study was conducted in a group of 18 subjects after chronic stroke who underwent robot therapy of the upper limb. We used two different measures of movement dynamics to assess patients' performance during each session of training: the nFCP and force directional error (FDE), both measuring the directional error of the patient-exerted force applied to the end-effector of the robot device. Both metrics exhibited significant changes over the three-week course of treatment. The comparison between nFCP and FDE slopes showed a signific... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334995 Mon, 01 Feb 2010 00:00:00 +0100 3334995 http://www.medworm.com/index.php?rid=3334994&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5339214 We present versatile multifunctional programmable controller with bidirectional data telemetry, implemented using existing commercial microchips and standard Bluetooth protocol, which adds convenience, reliability, and ease-of-use to neuroprosthetic devices. Controller, weighing 190 g, is placed on animal's back and provides bidirectional sustained telemetry rate of 500 kb/s , allowing real-time control of stimulation parameters and viewing of acquired data. In continuously-active state, controller consumes $sim$420 mW and operates without recharge for 8 h . It features independent 16-channel current-controlled stimulation, allowing current steering; customizable stimulus current waveforms; recording of stimulus voltage waveforms and evoked neuronal responses with stimulus artifact blankin... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334994 Mon, 01 Feb 2010 00:00:00 +0100 3334994 http://www.medworm.com/index.php?rid=3334993&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5378626 We present a new wearable haptic device that provides a sense of position and motion by inducing rotational skin stretch on the user's skin. In the experiments described in this paper, the device was used to provide proprioceptive feedback from a virtual prosthetic arm controlled with myoelectric sensors on the bicep and tricep muscles in 15 able-bodied participants. Targeting errors in blind movements with the haptic device were compared to cases where no feedback and contralateral proprioception were provided. Average errors were lower with the device than with no feedback but larger than with contralateral proprioceptive feedback. Participants also had lower visual demand with the device than with no feedback while tracking a 30 $^circ$ moving range. The results indicate that the rotati... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334993 Mon, 01 Feb 2010 00:00:00 +0100 3334993 http://www.medworm.com/index.php?rid=3334992&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5378611 This paper describes a novel pattern recognition based myoelectric control system that uses parallel binary classification and class specific thresholds. The system was designed with an intuitive configuration interface, similar to existing conventional myoelectric control systems. The system was assessed quantitatively with a classification error metric and functionally with a clothespin test implemented in a virtual environment. For each case, the proposed system was compared to a state-of-the-art pattern recognition system based on linear discriminant analysis and a conventional myoelectric control scheme with mode switching. These assessments showed that the proposed control system had a higher classification error $({ p}<0.001)$ but yielded a more controllable myoelectric cont... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334992 Mon, 01 Feb 2010 00:00:00 +0100 3334992 http://www.medworm.com/index.php?rid=3334991&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5280197 Gait rehabilitation robots are of increasing importance in neurorehabilitation. Conventional devices are often criticized because they are limited to reproducing predefined movement patterns. Research on patient-cooperative control strategies aims at improving robotic behavior. Robots should support patients only as much as needed and stimulate them to produce maximal voluntary efforts. This paper presents a patient-cooperative strategy that allows patients to influence the timing of their leg movements along a physiologically meaningful path. In this “path control” strategy, compliant virtual walls keep the patient's legs within a “tunnel” around the desired spatial path. Additional supportive torques enable patients to move along the path with reduced effort. ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334991 Mon, 01 Feb 2010 00:00:00 +0100 3334991 http://www.medworm.com/index.php?rid=3334990&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5378599 This study investigated the redistribution of external buttock load in relation to the pattern (i.e., dynamics) of subtuberal blood supply in sitting with a dynamic tuberal support of 1/60 Hz (80 mm/min). Fifteen healthy male subjects were seated with their ITs on the TSE. The experiment involved periodic TSE adjustment in which buttock interface pressure was measured with the FSP and an external pressure mapping device (PMD). Light-guide tissue spectrophotometry was used for simultaneous noninvasive measurement of oxygenation and perfusion in the skin ($<$ 2 mm) and subcutaneous ($<$ 8 mm) tissue under the ITs. TSE adjustment seemed effective to regulate centre of buttock pressure and the forces under the ITs. Differences in measurement with the FSP and PMD have been found... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334990 Mon, 01 Feb 2010 00:00:00 +0100 3334990 http://www.medworm.com/index.php?rid=3334989&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5256301 A relevant issue in a brain–computer interface (BCI) is the capability to efficiently convert user intentions into correct actions, and how to properly measure this efficiency. Usually, the evaluation of a BCI system is approached through the quantification of the classifier performance, which is often measured by means of the information transfer rate (ITR). A shortcoming of this approach is that the control interface design is neglected, and hence a poor description of the overall performance is obtained for real systems. To overcome this limitation, we propose a novel metric based on the computation of BCI Utility. The new metric can accurately predict the overall performance of a BCI system, as it takes into account both the classifier and the control interface characteristics. ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334989 Mon, 01 Feb 2010 00:00:00 +0100 3334989 http://www.medworm.com/index.php?rid=3334988&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5166505 In this paper, a novel approach to examine the cortical functional connectivity using multichannel electroencephalographic (EEG) signals is proposed. First we utilized independent component analysis (ICA) to transform multichannel EEG recordings into independent processes and then applied source reconstruction algorithm [i.e., standardize low resolution brain electromagnetic (sLORETA)] to identify the cortical regions of interest (ROIs). Second, we performed a graph theory analysis of the bipartite network composite of ROIs and independent processes to assess the connectivity between ROIs. We applied this proposed algorithm and compared the functional connectivity network properties under resting state condition using 29 student-athletes prior to and shortly after sport-related mild trauma... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334988 Mon, 01 Feb 2010 00:00:00 +0100 3334988 http://www.medworm.com/index.php?rid=3334987&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5378616 Subretinal implants are the subject of clinical investigation for their ability to evoke useful visual sensations in blind individuals via electrical stimulation of the diseased retina. We investigated the spatial characteristic of the retinal polarization obtained by electric field stimulation through a subretinally located monopolar electrode array and bipolar electrode array. By combining electric potential simulation through a boundary element method with a segmented cell model, we computed the membrane voltage at the axon terminal of the bipolar cells as a function of the axon length (50–110 $mu {rm m}$) and the electrode diameter. We found that short OFF bipolar cells are predominantly addressed by small bipolar electrodes (diameter between 60 and 100 $ mu{rm m}$) and by using... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3334987 Mon, 01 Feb 2010 00:00:00 +0100 3334987 http://www.medworm.com/index.php?rid=3334986&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5420312 (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=3334986 Mon, 01 Feb 2010 00:00:00 +0100 3334986 http://www.medworm.com/index.php?rid=3334985&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5420309%26arnumber%3D5420310 (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=3334985 Mon, 01 Feb 2010 00:00:00 +0100 3334985 http://www.medworm.com/index.php?rid=3185121&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5382609 (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=3185121 Tue, 01 Dec 2009 00:00:00 +0100 3185121 http://www.medworm.com/index.php?rid=3153162&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5371955 (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=3153162 Tue, 01 Dec 2009 00:00:00 +0100 3153162 http://www.medworm.com/index.php?rid=3153161&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5371952 (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=3153161 Tue, 01 Dec 2009 00:00:00 +0100 3153161 http://www.medworm.com/index.php?rid=3153160&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5371947 (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=3153160 Tue, 01 Dec 2009 00:00:00 +0100 3153160 http://www.medworm.com/index.php?rid=3153159&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5371950 (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=3153159 Tue, 01 Dec 2009 00:00:00 +0100 3153159 http://www.medworm.com/index.php?rid=3153158&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5368692 (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=3153158 Tue, 01 Dec 2009 00:00:00 +0100 3153158 http://www.medworm.com/index.php?rid=3153157&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5368706 In the above titled paper (ibid., vol. 17, no. 5, pp. 420-427, Oct. 09), Fig. 5 should have appeared as it is presented here. (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=3153157 Tue, 01 Dec 2009 00:00:00 +0100 3153157 http://www.medworm.com/index.php?rid=3153156&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5371963 In the above titled paper (ibid., vol. 17, no. 3, pp. 263-269, Jun. 09), the last paragraph of Section IV should appear as it is presented here. (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=3153156 Tue, 01 Dec 2009 00:00:00 +0100 3153156 http://www.medworm.com/index.php?rid=3153155&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5196802 Robot-assisted training is increasingly being investigated in upper limb rehabilitation for individuals with stroke. Many studies have suggested that an appropriate synchronization of voluntary motor commands and limb movement is critical for long-term efficacy. Bimanual training is one method for enhancing this synchronization or motor coordination. The purpose of the study was to evaluate the potential efficacy of bimanual robot-assisted movements by comparing the relative timing of muscle activation and forces to those generated during unimanual robot-assisted movement. A secondary goal was to compare bimanual robot-assisted movement to bimanual voluntary movement, where both limbs moved independently without robotics. Subjects performed reaching tasks while attached to one or two robot... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153155 Tue, 01 Dec 2009 00:00:00 +0100 3153155 http://www.medworm.com/index.php?rid=3153154&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5349073 This study investigated the classification accuracy of a combined surface electromyographic (sEMG) and accelerometer (ACC) sensor system for monitoring activities of daily living in patients with stroke. sEMG and ACC data (eight channels each) were recorded from 10 hemiparetic patients while they carried out a sequence of 11 activities of daily living (identification tasks), and 10 activities used to evaluate misclassification errors (nonidentification tasks). The sEMG and ACC sensor data were analyzed using a multilayered neural network and an adaptive neuro-fuzzy inference system to identify the minimal sensor configuration needed to accurately classify the identification tasks, with a minimal number of misclassifications from the nonidentification tasks. The results demonstrated that th... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153154 Tue, 01 Dec 2009 00:00:00 +0100 3153154 http://www.medworm.com/index.php?rid=3153153&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5061582 A high-level objective of neuromuscular electrical stimulation (NMES) is to enable a person to achieve some functional task. Towards this goal, the objective of the current effort is to develop a NMES controller to produce a knee position trajectory that will enable a human shank to track any continuous desired trajectory (or constant setpoint). A nonlinear control method is developed to control the human quadriceps femoris muscle undergoing nonisometric contractions. The developed controller does not require a muscle model and can be proven to yield asymptotic stability for a nonlinear muscle model in the presence of bounded nonlinear disturbances (e.g., spasticity, delays, fatigue). The performance of the controller is demonstrated through a series of closed-loop experiments on human sub... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153153 Tue, 01 Dec 2009 00:00:00 +0100 3153153 http://www.medworm.com/index.php?rid=3153152&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5299280 Effective clinical trials for neuroprotective interventions for Parkinson's disease (PD) require a way to quantify an individual's motor symptoms and analyze the change in these symptoms over time. Clinical scales provide a global picture of function but cannot precisely measure specific aspects of motor control. We have used commercially available sensors to create a protocol called Advanced Sensing for Assessment of Parkinson's disease (ASAP) to obtain a quantitative and reliable measure of motor impairment in early to moderate PD. The ASAP protocol measures grip force as an individual tracks a sinusoidal or pseudorandom target force under three conditions of increasing cognitive load. Thirty individuals with PD have completed the ASAP protocol. The ASAP data for 26 of these individuals ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153152 Tue, 01 Dec 2009 00:00:00 +0100 3153152 http://www.medworm.com/index.php?rid=3153151&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D4956985 Tactile sensory feedback is essential for dexterous object manipulation. Users of hand myoelectric prostheses without tactile feedback must depend essentially on vision to control their device. Indeed, improved tactile feedback is one of their main priorities. Previous research has provided evidence that conveying tactile feedback can improve prostheses control, although additional effort is required to solve problems related to pattern recognition learning, unpleasant sensations, sensory adaptation, and low spatiotemporal resolution. Still, these studies have mainly focused on providing stimulation to hairy skin regions close to the amputation site, i.e., usually to the upper arm. Here, we explored the possibility to provide tactile feedback to the glabrous skin of toes, which have mechan... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153151 Tue, 01 Dec 2009 00:00:00 +0100 3153151 http://www.medworm.com/index.php?rid=3153150&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5256298 Motions of the center of body mass (COM) and body segment acceleration signals are commonly used to indicate movement performance and stability during standing activities. The COM trajectory is usually calculated by video motion analysis, which has a time consuming setup and also is not readily available in all clinical settings. In this paper, we present a novel method to estimate the COM trajectory from the upper and lower limb accelerations, based on experimental data. We have modeled the relationships that exist between the 2-D hip and trunk acceleration data with the 2-D COM trajectory in the sagittal plane, during four trunk flexion–extension movement tasks and estimated the COM trajectory based on that model. The model accounted for between 93 $pm$ 9% to 97 $pm$ 3% of the res... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153150 Tue, 01 Dec 2009 00:00:00 +0100 3153150 http://www.medworm.com/index.php?rid=3153149&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5208177 The muscles of the hamstring group can produce different combinations of hip and knee torque. Thus, the ability to activate the different hamstring muscles selectively is of particular importance in eliciting functional movements such as stance and gait in a person with spinal cord injury. We investigated the ability of intrafascicular stimulation of the muscular branch of the sciatic nerve to recruit the feline hamstring muscles in a selective and graded fashion. A Utah Slanted Electrode Array, consisting of 100 penetrating microelectrodes, was implanted into the muscular branch of the sciatic nerve in six cats. Muscle twitches were evoked in the three compartments of biceps femoris (anterior, middle, and posterior), as well as semitendinosus and semimembranosus, using pulse-width modulat... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153149 Tue, 01 Dec 2009 00:00:00 +0100 3153149 http://www.medworm.com/index.php?rid=3153148&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5196803 The application of high-frequency alternating current (HFAC) stimulation to reversibly block conduction in peripheral nerves has been under investigation for decades. Computational studies have produced ambiguous results since they have been based on axon models that are perhaps not valid for the nerves in which the phenomenon has been demonstrated. Though simulations based on the Hodgkin–Huxley unmyelinated nerve cable model have been used to understand the phenomena, the isolated response of an unmyelinated nerve to HFAC waveforms has not been experimentally investigated. To understand the effect of HFAC waveforms in homogenous nerves, experiments were conducted on purely unmyelinated nerves of the sea-slug Aplysia californica. Sinusoidal waveforms in the range of 5–50 kHz ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153148 Tue, 01 Dec 2009 00:00:00 +0100 3153148 http://www.medworm.com/index.php?rid=3153147&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5256259 We have recently shown that click evoked auditory brainstem responses (ABRs) can be efficiently processed using a novelty detection paradigm. Here, ABRs as a large-scale reflection of a stimulus locked neuronal group synchronization at the brainstem level are detected as novel instance—novel as compared to the spontaneous activity which does not exhibit a regular stimulus locked synchronization. In this paper we propose for the first time Gabor frame operators as an efficient feature extraction technique for ABR single sweep sequences that is in line with this paradigm. In particular, we use this decomposition technique to derive the Gabor frame phase stability (GFPS) of sweep sequences of click and chirp evoked ABRs. We show that the GFPS of chirp evoked ABRs provides a stable disc... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153147 Tue, 01 Dec 2009 00:00:00 +0100 3153147 http://www.medworm.com/index.php?rid=3153146&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5166506 Current brain–computer interface (BCI) systems suffer from high complex feature selectors in comparison to simple classifiers. Meanwhile, neurophysiological and experimental information are hard to be included in these two separate phases. In this paper, based on the hierarchical observation model, we proposed an empirical Bayesian linear discriminant analysis (BLDA), in which the neurophysiological and experimental priors are considered simultaneously; the feature selection, weighted differently, and classification are performed jointly, thus it provides a novel systematic algorithm framework which can utilize priors related to feature and trial in the classifier design in a BCI. BLDA was comparatively evaluated by two simulations of a two-class and a four-class problem, and then i... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=3153146 Tue, 01 Dec 2009 00:00:00 +0100 3153146 http://www.medworm.com/index.php?rid=3153145&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5373720 (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=3153145 Tue, 01 Dec 2009 00:00:00 +0100 3153145 http://www.medworm.com/index.php?rid=3153144&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5349072%26arnumber%3D5373719 (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=3153144 Tue, 01 Dec 2009 00:00:00 +0100 3153144 http://www.medworm.com/index.php?rid=2967032&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5308703 (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=2967032 Thu, 01 Oct 2009 00:00:00 +0100 2967032 http://www.medworm.com/index.php?rid=2967031&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5308705 (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=2967031 Thu, 01 Oct 2009 00:00:00 +0100 2967031 http://www.medworm.com/index.php?rid=2967030&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5196799 Current neuroscience has identified several constructs to increase the effectiveness of upper extremity rehabilitation. One is the use of progressive, skill acquisition-oriented training. Another approach emphasizes the use of bilateral activities. Building on these principles, this paper describes the design and feasibility testing of a robotic/virtual environment system designed to train the arm of persons who have had strokes. The system provides a variety of assistance modes, scalable workspaces and hand–robot interfaces allowing persons with strokes to train multiple joints in three dimensions. The simulations utilize assistance algorithms that adjust task difficulty both online and offline in relation to subject performance. Several distinctive haptic effects have been incorpo... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967030 Thu, 01 Oct 2009 00:00:00 +0100 2967030 http://www.medworm.com/index.php?rid=2967029&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5196809 Over the past decade, research in the field of functional electrical stimulation (FES) has led to a new generation of high-electrode-count (HEC) devices that offer increasingly selective access to neural populations. Incorporation of these devices into research and clinical applications, however, has been hampered by the lack of hardware and software platforms capable of taking full advantage of them. In this paper, we present the first generation of a closed-loop FES platform built specifically for HEC neural interface devices. The platform was designed to support a wide range of stimulus-response mapping and feedback-based control routines. It includes a central control module, a 1100-channel stimulator, an array of biometric devices, and a 160-channel data recording module. To demonstra... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967029 Thu, 01 Oct 2009 00:00:00 +0100 2967029 http://www.medworm.com/index.php?rid=2967028&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5061590 Currently, stance-control knee orthoses require external control mechanisms to control knee flexion during stance and allow free knee motion during the swing phase of gait. A new angular-velocity control approach that uses a rotary-hydraulic device to resist knee flexion when the knee angular velocity passes a preset threshold is presented. This angular-velocity approach for orthotic stance control is based on the premise that knee-flexion angular velocity during a knee-collapse event, such as a stumble or fall, is greater than that during walking. The new hydraulic knee-flexion control device does not require an external control mechanism to switch from free motion to stance control mode. Functional test results demonstrated that the hydraulic angular-velocity activated knee joint provide... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967028 Thu, 01 Oct 2009 00:00:00 +0100 2967028 http://www.medworm.com/index.php?rid=2967027&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5196801 Although most brain–machine interface (BMI) studies have focused on decoding kinematic parameters of motion such as hand position and velocity, it is known that motor cortical activity also correlates with kinetic signals, including active hand force and joint torque. Here, we attempted to reconstruct torque trajectories of the shoulder and elbow joints from the activity of simultaneously recorded units in primary motor cortex (MI) as monkeys (Macaca Mulatta) made reaching movements in the horizontal plane. Using a linear filter decoding approach that considers the history of neuronal activity up to one second in the past, we found torque reconstruction performance nearly equal to that of Cartesian hand position and velocity, despite the considerably greater bandwidth of the torque ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967027 Thu, 01 Oct 2009 00:00:00 +0100 2967027 http://www.medworm.com/index.php?rid=2967026&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5308701 Cable theory is used to model fibers (neural or muscular) subjected to an extracellular stimulus or activating function along the fiber (longitudinal stimulation). There are cases however, in which activation from fields across a fiber (transverse stimulation) is dominant and the activating function is insufficient to predict the relative stimulus thresholds for cells in a bundle. This work proposes a general method of quantifying transverse extracellular stimulation using ideal cases of long fibers oriented perpendicular to a uniform field (circular cells in a 2-D extracellular domain). Several methods are compared against a fully coupled model to compute electrical potentials around each cell of a bundle and predict the magnitude of applied plate potential $({mitPhi}_{p})$ needed to acti... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967026 Thu, 01 Oct 2009 00:00:00 +0100 2967026 http://www.medworm.com/index.php?rid=2967025&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5288619 Many medical conditions are characterized by undesired or pathological peripheral neurological activity. The local delivery of high-frequency alternating currents (HFAC) has been shown to be a fast acting and quickly reversible method of blocking neural conduction and may provide a treatment alternative for eliminating pathological neural activity in these conditions. This work represents the first formal study of electrode design for high-frequency nerve block, and demonstrates that the interpolar separation distance for a bipolar electrode influences the current amplitudes required to achieve conduction block in both computer simulations and mammalian whole nerve experiments. The minimal current required to achieve block is also dependent on the diameter of the fibers being blocked and t... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967025 Thu, 01 Oct 2009 00:00:00 +0100 2967025 http://www.medworm.com/index.php?rid=2967024&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5288620 The peripheral nervous system carries sensory and motor information that could be useful as command signals for function restoration in areas such as neural prosthetics and functional electrical stimulation (FES). Nerve cuff electrodes provide a robust and safe technique for recording nerve signals. However, a method to separate and recover signals from individual fascicles is necessary. Prior knowledge of the electrode geometry was used to develop an algorithm which assumes neither signal independence nor detailed knowledge of the nerve's geometry/conductivity, and is applicable to any wide-band near-field situation. When used to recover fascicular activities from simulated nerve cuff recordings in a realistic human femoral nerve model, this beamforming algorithm separates signals as clos... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967024 Thu, 01 Oct 2009 00:00:00 +0100 2967024 http://www.medworm.com/index.php?rid=2967023&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5233787 We have demonstrated that micro-channel electrode arrays with $100 mu{rm m}times 100 mu{rm m}$ cross-section channels support axon regeneration well, and that micro-channels of similar calibre and up to 5 mm long can support axon regeneration and vascularisation. They may be microfabricated using silicon, silicone, or polyimide and thin metal films to form 3-D bundles of long micro-channels. Arrays of “mini-nerves,” i.e., miniature nerve fascicles with their own blood vessels, successfully grew through implants 0.5–5 mm long. Furthermore, guiding the regenerating nerve fibres into the small insulating channels allows for a significant increase of the extracellular (recordable) amplitude of action potentials, which promises considerable improvement for in vivo electroph... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967023 Thu, 01 Oct 2009 00:00:00 +0100 2967023 http://www.medworm.com/index.php?rid=2967022&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5256297 In this study, we explored the feasibility of estimating muscle length in passive conditions by interpreting nerve responses from muscle spindle afferents recorded with thin-film longitudinal intrafascicular electrodes. Afferent muscle spindle response to passive stretch was recorded in ten acute rabbit experiments. A newly proposed first-order model of muscle spindle response to passive sinusoidal muscle stretch manages to capture the relationship between afferent neural firing rate and muscle length. We demonstrate that the model can be used to track random motion trajectories with bandwidth from 0.1 to 1 Hz over a range of 4 mm with a muscle length estimation error of 0.3 mm (1.4$^circ$ of joint angle). When estimation is performed using four-channel ENG there is a 50% reduction in esti... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967022 Thu, 01 Oct 2009 00:00:00 +0100 2967022 http://www.medworm.com/index.php?rid=2967021&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5256278 This study quantified the ability of three amputee subjects who had undergone TR surgery on the chest (two subjects) and upper arm (one subject) to discriminate changes in graded force on their reinnervated skin over a range of 1–4 N using a stochastic staircase approach. These values were compared to those from sites on their intact contralateral skin and index fingers, and from the chests and index fingers of a control population $(n=10)$ . Weber's ratio (WR) was used to examine the subjects' abilities to discriminate between a baseline force and subsequent forces of different magnitudes. WRs of 0.22, 0.25, and 0.12 were measured on the reinnervated skin of the three TR subjects, whereas WRs of 0.25, 0.23, and 0.12 were measured on their contralateral skin. TR subjects did not hav... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967021 Thu, 01 Oct 2009 00:00:00 +0100 2967021 http://www.medworm.com/index.php?rid=2967020&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5256276 The objective of this study was to look at the long term nerve and muscle response to stimulation through nerve cuff electrodes. The nerve conduction velocity remained within the clinically accepted range for the entire testing period. The stimulation thresholds stabilized after approximately 20 weeks. The variability in the activation over time was not different from muscle-based electrodes used in implanted functional electrical stimulation systems. Three electrodes had multiple, independent contacts to evaluate selective recruitment of muscles. A single muscle could be selectively activated from each electrode using single-contact stimulation and the selectivity was increased with the use of field steering techniques. The selectivity after three years was consistent with selectivity mea... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967020 Thu, 01 Oct 2009 00:00:00 +0100 2967020 http://www.medworm.com/index.php?rid=2967019&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5061587 A 56-contact matrix nerve cuff electrode (seven rings with eight contacts each) was used to obtain recordings from the rat sciatic nerve, which were then discriminated as originating from one of three fascicles (tibial, peroneal, and sural branches). The influence of the number and location of the recording contacts on the classification accuracy was studied. The performance of a classifier was shown to be superior when data was available from all 56 contacts, compared to when only the eight contacts of the middle ring were used (as in previously proposed multicontact tripolar cuff designs). By examining the performance variations as contacts were included one at a time (in order of decreasing positive impact on performance), it was further shown that the matrix configuration could outperf... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2967019 Thu, 01 Oct 2009 00:00:00 +0100 2967019 http://www.medworm.com/index.php?rid=2967018&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5308702 (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=2967018 Thu, 01 Oct 2009 00:00:00 +0100 2967018 http://www.medworm.com/index.php?rid=2967017&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5308704 (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=2967017 Thu, 01 Oct 2009 00:00:00 +0100 2967017 http://www.medworm.com/index.php?rid=2967016&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5308700%26arnumber%3D5308706 (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=2967016 Thu, 01 Oct 2009 00:00:00 +0100 2967016 http://www.medworm.com/index.php?rid=2691335&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5200720 (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=2691335 Fri, 31 Jul 2009 23:00:00 +0100 2691335 http://www.medworm.com/index.php?rid=2691334&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5200719 (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=2691334 Fri, 31 Jul 2009 23:00:00 +0100 2691334 http://www.medworm.com/index.php?rid=2691333&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5200716 (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=2691333 Fri, 31 Jul 2009 23:00:00 +0100 2691333 http://www.medworm.com/index.php?rid=2691332&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D4813270 Conductive elastomers are a novel strain sensing technology which can be unobtrusively embedded into a garment's fabric, allowing a new type of sensorized cloths for motion analysis. A possible application for this technology is remote monitoring and control of motor rehabilitation exercises. The present work describes a sensorized shirt for upper limb posture recognition. Supervised learning techniques have been employed to compare classification models for the analysis of strains, simultaneously measured at multiple points of the shirt. The instantaneous position of the limb was classified into a finite set of predefined postures, and the movement was decomposed in an ordered sequence of discrete states. The amount of information given by the observation of each sensor during the executi... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691332 Fri, 31 Jul 2009 23:00:00 +0100 2691332 http://www.medworm.com/index.php?rid=2691331&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5061591 We investigated the influence of feedback conditions on the effectiveness of a balance prosthesis. The balance prosthesis used an array of 12 tactile vibrators (tactors) placed on the anterior and posterior surfaces of the torso to provide body orientation feedback related to several different combinations of angular position and velocity of body sway in the sagittal plane. Control tests were performed with no tactor activation. Body sway was evoked in subjects with normal sensory function by rotating the support surface upon which subjects stood with eyes closed. Body sway was analyzed by computing root mean square sway measures and by a frequency-response function analysis that characterized the amplitude (gain) and timing (phase) of body sway over a frequency range of 0.017–2.2 H... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691331 Fri, 31 Jul 2009 23:00:00 +0100 2691331 http://www.medworm.com/index.php?rid=2691330&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5061579 With the increased presence of microprocessor-based prostheses in the market place, the availability of a self-energizing system has practical applicability. At present, most commercially available systems require the user to routinely recharge on-board batteries, which reduces the utility of these prostheses. To address this limitation, we have proposed a unique system based on an electromechanical generator to not only continually recharge batteries that are on-board the prostheses, but to also serve as a real time swing-phase damper. A prototype system was developed and evaluated with three active individuals with above-knee amputations across four damping conditions and two gait speeds. Gait and power generation performance were assessed via selected temporal, kinematic and kinetic par... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691330 Fri, 31 Jul 2009 23:00:00 +0100 2691330 http://www.medworm.com/index.php?rid=2691329&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5061583 We measured the forces produced at the cat's hindpaw by microstimulation of the lumbar spinal cord and the movements resulting from those forces. We also measured the forces and movements produced by co- and sequential activation of two intraspinal sites. Isometric force responses were measured at nine limb configurations with the paw attached to a force transducer. The active forces elicited at different limb configurations were summarized as patterns representing the sagittal plane component of the forces produced at the paw throughout the workspace. The force patterns divided into the same distinct types found with the femur fixed. The responses during simultaneous activation of two spinal sites always resembled the response for activation of one of the two sites, i.e., winner-take-all,... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691329 Fri, 31 Jul 2009 23:00:00 +0100 2691329 http://www.medworm.com/index.php?rid=2691328&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5061589 The Kalman filter has been proposed as a model to decode neural activity measured from the motor cortex in order to obtain real-time estimates of hand motion in behavioral neurophysiological experiments. However, currently used linear state-space models underlying the Kalman filter do not take into account other behavioral states such as muscular activity or the subject's level of attention, which are often unobservable during experiments but may play important roles in characterizing neural controlled hand movement. To address this issue, we depict these unknown states as one multidimensional hidden state in the linear state-space framework. This new model assumes that the observed neural firing rate is directly related to this hidden state. The dynamics of the hand state are also allowed... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691328 Fri, 31 Jul 2009 23:00:00 +0100 2691328 http://www.medworm.com/index.php?rid=2691327&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D4982702 In this study we propose a new method for long-term correlation analysis of neuronal burst activity based on the periodogram $alpha$ slope estimation of the MEA signal. We applied our method to recordings taken from cultured networks of dissociated rat cortical neurons. We show the effectiveness of the method in analyzing the activity changes as well as the temporal dynamics that take place during the development of such cultures. Results demonstrate that the $alpha$ parameter is able to divide the network development in three well-defined stages, showing pronounced variations in the long-term correlation among bursts. (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=2691327 Fri, 31 Jul 2009 23:00:00 +0100 2691327 http://www.medworm.com/index.php?rid=2691326&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5061588 We have used a well-known technique in wireless communication, pulse width modulation (PWM) of time division multiplexed (TDM) signals, within the architecture of a novel wireless integrated neural recording (WINeR) system. We have evaluated the performance of the PWM-based architecture and indicated its accuracy and potential sources of error through detailed theoretical analysis, simulations, and measurements on a setup consisting of a 15-channel WINeR prototype as the transmitter and two types of receivers; an Agilent 89600 vector signal analyzer and a custom wideband receiver, with 36 and 75 MHz of maximum bandwidth, respectively. Furthermore, we present simulation results from a realistic MATLAB-Simulink model of the entire WINeR system to observe the system behavior in response to ch... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691326 Fri, 31 Jul 2009 23:00:00 +0100 2691326 http://www.medworm.com/index.php?rid=2691325&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D4813269 We present a low-power complementary metal–oxide semiconductor (CMOS) analog integrated biopotential detector intended for neural recording in wireless multichannel implants. The proposed detector can achieve accurate automatic discrimination of action potential (APs) from the background activity by means of an energy-based preprocessor and a linear delay element. This strategy improves detected waveforms integrity and prompts for better performance in neural prostheses. The delay element is implemented with a low-power continuous-time filter using a ninth-order equiripple allpass transfer function. All circuit building blocks use subthreshold OTAs employing dedicated circuit techniques for achieving ultra low-power and high dynamic range. The proposed circuit function in the submic... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691325 Fri, 31 Jul 2009 23:00:00 +0100 2691325 http://www.medworm.com/index.php?rid=2691324&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5067358 We have built a wireless implantable microelectronic device for transmitting cortical signals transcutaneously. The device is aimed at interfacing a cortical microelectrode array to an external computer for neural control applications. Our implantable microsystem enables 16-channel broadband neural recording in a nonhuman primate brain by converting these signals to a digital stream of infrared light pulses for transmission through the skin. The implantable unit employs a flexible polymer substrate onto which we have integrated ultra-low power amplification with analog multiplexing, an analog-to-digital converter, a low power digital controller chip, and infrared telemetry. The scalable 16-channel microsystem can employ any of several modalities of power supply, including radio frequency b... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691324 Fri, 31 Jul 2009 23:00:00 +0100 2691324 http://www.medworm.com/index.php?rid=2691323&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5061581 Neural prosthetic systems have the potential to restore lost functionality to amputees or patients suffering from neurological injury or disease. Current systems have primarily been designed for immobile patients, such as tetraplegics functioning in a rather static, carefully tailored environment. However, an active patient such as amputee in a normal dynamic, everyday environment may be quite different in terms of the neural control of movement. In order to study motor control in a more unconstrained natural setting, we seek to develop an animal model of freely moving humans. Therefore, we have developed and tested HermesC-INI3, a system for recording and wirelessly transmitting neural data from electrode arrays implanted in rhesus macaques who are freely moving. This system is based on t... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691323 Fri, 31 Jul 2009 23:00:00 +0100 2691323 http://www.medworm.com/index.php?rid=2691322&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5061585 We present benchtop and in vivo experimental results from an integrated circuit designed for wireless implantable neural recording applications. The chip, which was fabricated in a commercially available 0.6- $mu$m 2P3M BiCMOS process, contains 100 amplifiers, a 10-bit analog-to-digital converter (ADC), 100 threshold-based spike detectors, and a 902–928 MHz frequency-shift-keying (FSK) transmitter. Neural signals from a selected amplifier are sampled by the ADC at 15.7 kSps and telemetered over the FSK wireless data link. Power, clock, and command signals are sent to the chip wirelessly over a 2.765-MHz inductive (coil-to-coil) link. The chip is capable of operating with only two off-chip components: a power/command receiving coil and a 100-nF capacitor. (Source: IEE Transactions on... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691322 Fri, 31 Jul 2009 23:00:00 +0100 2691322 http://www.medworm.com/index.php?rid=2691321&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D4912399 This paper reports a 128-channel neural recording integrated circuit (IC) with on-the-fly spike feature extraction and wireless telemetry. The chip consists of eight 16-channel front-end recording blocks, spike detection and feature extraction digital signal processor (DSP), ultra wideband (UWB) transmitter, and on-chip bias generators. Each recording channel has amplifiers with programmable gain and bandwidth to accommodate different types of biological signals. An analog-to-digital converter (ADC) shared by 16 amplifiers through time-multiplexing results in a balanced trade-off between the power consumption and chip area. A nonlinear energy operator (NEO) based spike detector is implemented for identifying spikes, which are further processed by a digital frequency-shaping filter. The com... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2691321 Fri, 31 Jul 2009 23:00:00 +0100 2691321 http://www.medworm.com/index.php?rid=2691320&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5200717 (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=2691320 Fri, 31 Jul 2009 23:00:00 +0100 2691320 http://www.medworm.com/index.php?rid=2691319&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5200721 (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=2691319 Fri, 31 Jul 2009 23:00:00 +0100 2691319 http://www.medworm.com/index.php?rid=2691318&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5200715%26arnumber%3D5200718 (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=2691318 Fri, 31 Jul 2009 23:00:00 +0100 2691318 http://www.medworm.com/index.php?rid=2508344&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5089924 (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=2508344 Sun, 31 May 2009 23:00:00 +0100 2508344 http://www.medworm.com/index.php?rid=2508343&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5089926 (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=2508343 Sun, 31 May 2009 23:00:00 +0100 2508343 http://www.medworm.com/index.php?rid=2508342&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5089928 (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=2508342 Sun, 31 May 2009 23:00:00 +0100 2508342 http://www.medworm.com/index.php?rid=2508341&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5061576 The usefulness of motor subtypes of delirium is unclear due to inconsistency in subtyping methods and a lack of validation with objective measures of activity. The activity of 40 patients was measured over 24 h with a discrete accelerometer-based activity monitor. The continuous wavelet transform (CWT) with various mother wavelets were applied to accelerometry data from three randomly selected patients with DSM-IV delirium that were readily divided into hyperactive, hypoactive, and mixed motor subtypes. A classification tree used the periods of overall movement as measured by the discrete accelerometer-based monitor as determining factors for which to classify these delirious patients. This data used to create the classification tree were based upon the minimum, maximum, standard deviation... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508341 Sun, 31 May 2009 23:00:00 +0100 2508341 http://www.medworm.com/index.php?rid=2508340&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D4785180 This paper presents a new learning method for Gaussian mixture models (GMMs) to improve their generalization ability. A traditional maximum a posterior (MAP) parameter estimate is used to achieve regularization based on conjugate priors. Plus, a model order selection criterion is derived from Bayesian–Laplace approaches, using the conjugate priors to measure the uncertainty of the estimated parameters. As a result, the proposed learning method avoids the possibility of convergence toward the boundary of the parameter space, and is also capable of selecting the optimal order for a GMM with more enhanced stability than conventional methods using a flat prior. When applying the proposed learning method to construct a GMM classifier for electromyogram (EMG) pattern recognition, the prop... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508340 Sun, 31 May 2009 23:00:00 +0100 2508340 http://www.medworm.com/index.php?rid=2508339&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D4909040 This study undertakes a simulation and validation experiment to provide guidelines regarding pointing device usage for quadriplegic individuals assisted by a newly developed integrated pointing device apparatus (IPDA). The simulation experiment involving 30 normal subjects whose upper limb movement was restricted by splints. Another 15 subjects with high level cervical spinal cord injury (SCI) were recruited for the validation study. All normal subjects employed six control modes for target-acquisition and drag-and-drop tasks using an IPDA to integrate common pointing devices. A previously designed software was used to evaluate the operational efficiency (OE), expressed as “able performance” (%AP), of the subjects. The experimental results indicated that the OE of normal subj... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508339 Sun, 31 May 2009 23:00:00 +0100 2508339 http://www.medworm.com/index.php?rid=2508338&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5061575 This study reports a novel adaptive experiment on eight subjects that allowed repeated measures post-hoc comparison of four supervised and three unsupervised adaptation paradigms. All supervised adaptation paradigms reduced error over time by at least 26% compared to the nonadapting classifier. Most unsupervised adaptation paradigms provided smaller reductions in error, due to frequent uncertainty of the correct class. One method that selected high-confidence samples showed the most practical implementation, although the other methods warrant future investigation. Supervised adaptation should be considered for incorporation into any clinically viable pattern recognition controller, and unsupervised adaptation should receive renewed interest in order to provide transparent adaptation. (Sour... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508338 Sun, 31 May 2009 23:00:00 +0100 2508338 http://www.medworm.com/index.php?rid=2508337&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D4796313 The potential benefits of functional electrically stimulated (FES) cycling for people with spinal cord injury (SCI) are limited by the power output (PO) attainable. To understand why PO and metabolic efficiency are low, it is helpful to distinguish the effect of the SCI from the effects of electrical stimulation. The purpose of this study was to determine the performance of electrically stimulated (ES) muscle under simpler conditions and in able-bodied people in order to answer two questions about the causes of the poor efficiency in FES cycling. Fifteen able-bodied subjects (26.6 years, six male) performed 5 min of intermittent isometric quadriceps contractions at 40% maximum voluntary contraction during both voluntary and ES activation. Subsequently, nine of them performed 5 min of ES in... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508337 Sun, 31 May 2009 23:00:00 +0100 2508337 http://www.medworm.com/index.php?rid=2508336&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5061577 Brain–machine interfaces (BMIs) hold a lot of promise for restoring some level of motor function to patients with neuronal disease or injury. Current BMI approaches fall into two broad categories—those that decode discrete properties of limb movement (such as movement direction and movement intent) and those that decode continuous variables (such as position and velocity). However, to enable the prosthetic devices to be useful for common everyday tasks, precise control of the forces applied by the end-point of the prosthesis (e.g., the hand) is also essential. Here, we used linear regression and Kalman filter methods to show that neural activity recorded from the motor cortex of the monkey during movements in a force field can be used to decode the end-point forces applied by... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508336 Sun, 31 May 2009 23:00:00 +0100 2508336 http://www.medworm.com/index.php?rid=2508335&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5061578 In this study, we suggest improvements in the selection of parameters for the estimation of ${rm TE}$ that significantly enhance its accuracy and robustness in identifying the direction and the level of information flow between observed data series generated by coupled complex systems. We show the application of the improved ${rm TE}$ method to long (in the order of days; approximately a total of 600 h across all patients), continuous, intracranial electroencephalograms (EEG) recorded in two different medical centers from four patients with focal temporal lobe epilepsy (TLE) for localization of their foci. All patients underwent ablative surgery of their clinically assessed foci. Based on a surrogate statistical analysis of the ${rm TE}$ results, it is shown that the identified potential f... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508335 Sun, 31 May 2009 23:00:00 +0100 2508335 http://www.medworm.com/index.php?rid=2508334&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D4627453 In this study one recently proposed method, maximizing coherence, was applied into the coherence analysis to estimate the latency by which the extensor carpi radialis electromyographic signals lagged behind the electroencephalographic time series with seven subcortical stroke subjects. Significantly prolonged conduction time was found in affected sides compared with the unaffected sides. The interhemispheric spatial displacement was also calculated using electrodes projection optimization and spherical surface laplacian. The results showed that the CMCoh could help investigate the cerebral reorganization after stroke. (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=2508334 Sun, 31 May 2009 23:00:00 +0100 2508334 http://www.medworm.com/index.php?rid=2508333&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D4703284 In this paper, different linear and nonlinear methodologies for the estimation of cortical connectivity from neuroelectric and hemodynamic measurements are reviewed and applied on common data set in order to highlight similarities and differences in the results. Different effective and functional connectivity methods were applied to motor and cognitive data sets, including structural equation modeling (SEM), directed transfer function (DTF), partial directed coherence (PDC), and direct directed transfer function (dDTF). Comparisons were made between the results in order to understand if, for a same dataset, effective and functional connectivity estimators can return the same cortical connectivity patterns. An application of a nonlinear method [phase synchronization index (PSI)] to similar ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508333 Sun, 31 May 2009 23:00:00 +0100 2508333 http://www.medworm.com/index.php?rid=2508332&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D4627457 While temporal lobe epilepsy (TLE) has been treatable with anti-seizure medications over the past century, there still remain a large percentage of patients whose seizures remain untreatable pharmacologically. To better understand and treat TLE, our laboratory uses several in vivo analytical techniques to estimate connectivity in epilepsy. This paper reviews two different connectivity-based approaches with an emphasis on application to the study of epilepsy. First, we present effective connectivity techniques, such as Granger causality, that has been used to assess the dynamic directional relationships among brain regions. These measures are used to better understand how seizure activity initiates, propagates, and terminates. Second, structural techniques, such as magnetic resonance imagin... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508332 Sun, 31 May 2009 23:00:00 +0100 2508332 http://www.medworm.com/index.php?rid=2508331&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D4703283 Current multielectrode techniques enable the simultaneous recording of spikes from hundreds of neurons. To study neural plasticity and network structure it is desirable to infer the underlying functional connectivity between the recorded neurons. Functional connectivity is defined by a large number of parameters, which characterize how each neuron influences the other neurons. A Bayesian approach that combines information from the recorded spikes (likelihood) with prior beliefs about functional connectivity (prior) can improve inference of these parameters and reduce overfitting. Recent studies have used likelihood functions based on the statistics of point-processes and a prior that captures the sparseness of neural connections. Here we include a prior that captures the empirical finding ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2508331 Sun, 31 May 2009 23:00:00 +0100 2508331 http://www.medworm.com/index.php?rid=2508330&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5089929 (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=2508330 Sun, 31 May 2009 23:00:00 +0100 2508330 http://www.medworm.com/index.php?rid=2508329&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5089925 (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=2508329 Sun, 31 May 2009 23:00:00 +0100 2508329 http://www.medworm.com/index.php?rid=2508328&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D5089923%26arnumber%3D5089927 (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=2508328 Sun, 31 May 2009 23:00:00 +0100 2508328 http://www.medworm.com/index.php?rid=2330150&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4812308 (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=2330150 Fri, 17 Apr 2009 04:00:00 +0100 2330150 http://www.medworm.com/index.php?rid=2330149&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4812311 (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=2330149 Fri, 17 Apr 2009 04:00:00 +0100 2330149 http://www.medworm.com/index.php?rid=2330148&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4812309 (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=2330148 Fri, 17 Apr 2009 04:00:00 +0100 2330148 http://www.medworm.com/index.php?rid=2330147&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4785195 In this study, we show that the combination of these limitations causes transient instabilities under certain conditions. Through physical experiments and simulations, we show that dynamic clamp instability is directly related to the sampling delay and the maximum simulated conductance being injected. It is exaggerated by insufficient electrode series resistance and capacitance compensation. Increasing the sampling rate of the dynamic clamp system increases dynamic clamp stability; however, this improvement, is constrained by how well the electrode series resistance and capacitance are compensated. At present, dynamic clamp sampling rates are justified solely on the temporal dynamics of the models being simulated; here we show that faster rates increase the stable range of operation for th... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330147 Fri, 17 Apr 2009 04:00:00 +0100 2330147 http://www.medworm.com/index.php?rid=2330146&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4812313 The importance of body sensor networks to monitor patients over a prolonged period of time has increased with an advance in home healthcare applications. Sensor nodes need to operate with very low-power consumption and under the constraint of limited memory capacity. Therefore, it is wasteful to digitize the sensor signal at a constant sample rate, given that the frequency contents of the signals vary with time. Adaptive sampling is established as a practical method to reduce the sample data volume. In this paper a low-power analog system is proposed, which adjusts the converter clock rate to perform a peak-picking algorithm on the second derivative of the input signal. The presented implementation does not require an analog-to-digital converter or a digital processor in the sample selecti... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330146 Fri, 17 Apr 2009 04:00:00 +0100 2330146 http://www.medworm.com/index.php?rid=2330145&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4685628 One of the goals of peripheral nerve cuff electrode development is the design of an electrode capable of selectively activating a specific population of axons in a common nerve trunk. Several designs such as the round spiral electrode or the flat interface nerve electrode (FINE) have shown such ability. However, multiple contact electrodes require many leads, making the implantation difficult and potentially damaging to the nerve. Taking advantage of the flat geometry of the FINE, multiplexers were embedded within the cuff electrode to reduce the number of leads needed to control 32 channels. The circuit was implemented on a polyimide film using off-the-shelf electronic components. The electronic module was surface-mounted directly onto the electrode's flat substrate. Two circuit designs w... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330145 Fri, 17 Apr 2009 04:00:00 +0100 2330145 http://www.medworm.com/index.php?rid=2330144&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4773251 Neurological disorders such as stroke impair locomotor control and result in abnormal 3-D gait kinematics. Establishment of effective rehabilitation strategies requires an understanding of how individual muscles contribute to pathological movement. Forward dynamic simulations account for complexities of interjoint coupling and can be used to predict dynamic muscle function. However to date, limited experimental validations of dynamic models have been performed. Our objective was to measure 3-D movement induced by the biceps femoris (BF), rectus femoris (RF), and vastus lateralis (VL) in limb configurations corresponding to the swing phase of gait, and to assess the biomechanical factors that affect dynamic function. Subjects were positioned in a robotic gait orthosis that included a compli... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330144 Fri, 17 Apr 2009 04:00:00 +0100 2330144 http://www.medworm.com/index.php?rid=2330143&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4785182 The ability to walk without the help of a caretaker enhances the quality of life for those who are bed-ridden or confined to a wheelchair. At present, most of the available gait rehabilitation robot systems have been designed to support the body weight externally. For gait training to be effective, a mobile body weight support (BWS) mechanism is needed. In mobile gait training robot systems, functions such as patient path following and constant BWS are important issues, particularly in dynamic environments. In the present study, two types of robotic systems were developed for gait rehabilitation. The first is known as the mobile manipulator type and the second the mobile vehicle type. The differences between the two systems in design and control are discussed. A control algorithm based on ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330143 Fri, 17 Apr 2009 04:00:00 +0100 2330143 http://www.medworm.com/index.php?rid=2330142&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4801968 The electrolarynx (EL) is a common rehabilitative speech aid for individuals who have undergone total laryngectomy, but they typically lack pitch control and require the exclusive use of one hand. The viability of using neck and face surface electromyography (sEMG) to control the onset, offset, and pitch of an EMG-controlled EL (EMG-EL) was studied. Eight individuals who had undergone total laryngectomy produced serial and running speech using a typical handheld EL and the EMG-EL while attending to real-time visual sEMG biofeedback. Running speech tokens produced with the EMG-EL were examined for naturalness by 10 listeners relative to those produced with a typical EL using a visual analog scale. Serial speech performance was assessed as the percentage of words that were fully voiced and p... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330142 Fri, 17 Apr 2009 04:00:00 +0100 2330142 http://www.medworm.com/index.php?rid=2330141&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4785192 Conventional brain computer interfaces rely on a guided calibration procedure to address the problem of considerable variations in electroencephalography (EEG) across human subjects. This calibration, however, implies inconvenience to the end users. In this paper, we propose an online-adaptive-learning method to address this problem for P300-based brain computer interfaces. By automatically capturing subject-specific EEG characteristics during online operation, this method allows a new user to start operating a P300-based brain–computer interface without guided (supervised) calibration. The basic principle is to first learn a generic model termed subject-independent model offline from EEG of a pool of subjects to capture common P300 characteristics. For a new user, a new model terme... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330141 Fri, 17 Apr 2009 04:00:00 +0100 2330141 http://www.medworm.com/index.php?rid=2330140&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4773249 Induced hypothermia has been broadly applied in neurological intensive care unit (NICU). Meanwhile, accidental hypothermia is also a threatening condition in daily life. It is meaningful to investigate the influences of temperature change on the cerebral blood flow (CBF). In the present study, temporal laser speckle image contrast analysis (tLASCA) was implemented to study the relative CBF change in cerebral artery, vein and capillary level under mild (35 $^{circ} {rm C}$) and moderate (32 $^{circ} {rm C}$) hypothermia. Twelve male Sprague-Dawley rats ($300 pm 50~{rm g}$) were anesthetized with sodium pentobarbital and randomly assigned to mild and moderate hypothermia groups ( ${ n}=9$ each). Laser speckle imaging (LSI) trials were acquired from baseline ( 37 $, ^{circ} {rm C}$ ), hypothe... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330140 Fri, 17 Apr 2009 04:00:00 +0100 2330140 http://www.medworm.com/index.php?rid=2330139&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4773250 Multivariate point processes are increasingly being used to model neuronal response properties in the cortex. Estimating the conditional intensity functions underlying these processes is important to characterize and decode the firing patterns of cortical neurons. This paper proposes a new approach for estimating these intensity functions directly from a compressed representation of the neurons' extracellular recordings. The approach is based on exploiting a sparse representation of the extracellular spike waveforms, previously demonstrated to yield near-optimal denoising and compression properties. We show that by restricting this sparse representation to a subset of projections that simultaneously preserve features of the spike waveforms in addition to the temporal characteristics of the... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330139 Fri, 17 Apr 2009 04:00:00 +0100 2330139 http://www.medworm.com/index.php?rid=2330138&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4685904 Single trial electroencephalogram (EEG) classification is essential in developing brain–computer interfaces (BCIs). However, popular classification algorithms, e.g., common spatial patterns (CSP), usually highly depend on the prior neurophysiologic knowledge for noise removing, although this knowledge is not always known in practical applications. In this paper, a novel tensor-based scheme is proposed for single trial EEG classification, which performs well without the prior neurophysiologic knowledge. In this scheme, EEG signals are represented in the spatial-spectral-temporal domain by the wavelet transform, the multilinear discriminative subspace is reserved by the general tensor discriminant analysis (GTDA), redundant indiscriminative patterns are removed by Fisher score, and th... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2330138 Fri, 17 Apr 2009 04:00:00 +0100 2330138 http://www.medworm.com/index.php?rid=2330137&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4785188 We present the 3-D EEG source images reconstructed by using the minimum norm least square (MNLS) method in combination with the functional magnetic resonance imaging (fMRI) statistical parametric mapping. For a group of five normal subjects, electroencephalogram (EEG) and fMRI signals responding to the full-view checkerboard pattern-reversal visual stimulation were recorded simultaneously and separately. The electrical activities in V1/V2 and V5 were successfully imaged in the N75-P100-N145 and P100-N145 components, respectively. The present results demonstrate the merits of high-resolution spatiotemporal functional neuroimaging by integrating the simultaneously recorded fMRI and EEG data. (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=2330137 Fri, 17 Apr 2009 04:00:00 +0100 2330137 http://www.medworm.com/index.php?rid=2330136&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4812310 (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=2330136 Fri, 17 Apr 2009 04:00:00 +0100 2330136 http://www.medworm.com/index.php?rid=2330135&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4812307%26arnumber%3D4812312 (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=2330135 Fri, 17 Apr 2009 04:00:00 +0100 2330135 http://www.medworm.com/index.php?rid=2261104&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4782183 (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=2261104 Sat, 14 Feb 2009 05:00:00 +0100 2261104 http://www.medworm.com/index.php?rid=2261103&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4782185 (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=2261103 Sat, 14 Feb 2009 05:00:00 +0100 2261103 http://www.medworm.com/index.php?rid=2261102&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4703207 The aim of the research is to develop an objective evaluation tool for use in stroke rehabilitation clinical practice. Stroke patients are prone to particularly high risk of fall, which may differ for various directions of movement. An apparatus enabling perturbations and postural response assessment in eight directions in transversal plane during standing was used to assess data in seven neurologically intact volunteers and 10 stroke patients before and after the rehabilitation. Ground reaction force and center of pressure were acquired during the perturbation, signal processed and compared to Berg Balance Scale (BBS), a clinical outcome measure of balance. The results of the weight load ratio between the affected and unaffected lower extremity demonstrated objective positive outcomes of ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261102 Sat, 14 Feb 2009 05:00:00 +0100 2261102 http://www.medworm.com/index.php?rid=2261101&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4703287 The overarching goal of this project is to provide shoulder and elbow function to individuals with C5/C6 spinal cord injury (SCI) using functional electrical stimulation (FES), increasing the functional outcomes currently provided by a hand neuroprosthesis. The specific goal of this study was to design a controller based on an artificial neural network (ANN) that extracts information from the activity of muscles that remain under voluntary control sufficient to predict appropriate stimulation levels for several paralyzed muscles in the upper extremity. The ANN was trained with activation data obtained from simulations using a musculoskeletal model of the arm that was modified to reflect C5 SCI and FES capabilities. Several arm movements were recorded from able-bodied subjects and these kin... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261101 Sat, 14 Feb 2009 05:00:00 +0100 2261101 http://www.medworm.com/index.php?rid=2261100&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4627454 Open loop and force controllers are compared experimentally with three robust parallel force-velocity controllers that are developed for a prosthetic hand. Robust sliding mode, backstepping, and hybrid sliding mode-backstepping (HSMBS) parallel force-velocity controllers are tested by ten able-bodied subjects. Results obtained with a myoelectrically controlled prosthesis indicate that all three robust controllers offer a statistically significant improvement over linear hand prosthesis control schemes. The robust controllers enable the human operators to more easily manipulate a delicate object. Bench top experiments combined with quantitative and qualitative evaluations from ten test subjects reveal the HSMBS controller to be the best choice to improve control of powered prosthetic hands.... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261100 Sat, 14 Feb 2009 05:00:00 +0100 2261100 http://www.medworm.com/index.php?rid=2261099&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4703282 An improved biomechanical model has been implemented for use in gait simulations and functional electrical stimulation (FES). The novelty includes longitudinal bending of the foot which implements geometrical changes that appear “healthy-like” during the stance phase of gait. The simulation uses optimal control which minimizes the activation of flexor and extensor muscles, as well as the tracking error. Correspondingly, the results of the bending foot model, contrasted against a rigid foot biomechanical model, show that torques in the knee during foot contact were as much as 36.9 Nm (46.1%) lower, while muscle excitation was on average 6.1% lower. The simulation also shows that the shank angle of the bending foot model was virtually identical to that of the rigid foot model. ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261099 Sat, 14 Feb 2009 05:00:00 +0100 2261099 http://www.medworm.com/index.php?rid=2261098&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4703285 A methodology is investigated for determining the location of active pathways in a peripheral nerve using measurements from a multicontact cuff electrode. The problem is treated as an inverse problem of source localization and solved using the sLORETA algorithm, developed for the electroencephalogram/magnetoencephalogram source localization problem. Simulated measurements are generated corresponding to action potentials traveling along either one or three pathways in a rat sciatic nerve. The performance of the proposed methodology using these measurements is evaluated in terms of localization error, missed pathways, and spurious pathways. The source localization performance when assuming an idealized nerve anatomy is compared to that when the correct anatomy is known. The effect of a spati... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261098 Sat, 14 Feb 2009 05:00:00 +0100 2261098 http://www.medworm.com/index.php?rid=2261097&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4703281 Auditory evoked cortical potentials (AECPs) have been consolidated as a diagnostic tool in audiology. Further applications of this technique are in experimental neuropsychology, neuroscience, and psychiatry, e.g., for the attention deficit disorder, schizophrenia, or for studying the tinnitus decompensation. In particular, numerous psychophysiological studies have emphasized their dynamic characteristics in relation to exogenous and endogenous attention. However, the effect of corticothalamic feedback dynamics to neural correlates of focal and nonfocal attention and its large-scale effect reflected in AECPs is far from being understood. To address this issue, we model neural correlates of auditory selective attention reflected in AECPs by using corticothalamic feedback dynamics. In our fra... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261097 Sat, 14 Feb 2009 05:00:00 +0100 2261097 http://www.medworm.com/index.php?rid=2261096&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4668437 This paper presents a novel reeducation device for paraplegics that combines hybrid orthoses and closed-loop electrical muscle stimulation. Based on the so called Cyberthosis concept, the WalkTrainer enables an active muscular participation of the subject in the walking reeducation process by the mean of closed-loop muscle stimulation. The WalkTrainer is also equipped with a leg and pelvic orthosis, an active bodyweight support, and motorized wheels to allow true over ground deambulation. This paper will focus on the development of the WalkTrainer, the presentation of the control strategies, and also give some preliminary results of the first clinical trials. (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=2261096 Sat, 14 Feb 2009 05:00:00 +0100 2261096 http://www.medworm.com/index.php?rid=2261095&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4668436 A previous study from our laboratory showed that when soleus electromyography was used to control the amount of plantar flexion assistance from a robotic ankle exoskeleton, subjects significantly reduced their soleus activity to quickly return to normal gait kinematics. We speculated that subjects were primarily responding to the local mechanical assistance of the exoskeleton rather than directly attempting to reduce exoskeleton mechanical power via decreases in soleus activity. To test this observation we studied ten healthy subjects walking on a treadmill at 1.25 m/s while wearing a robotic exoskeleton proportionally controlled by medial gastrocnemius activation. We hypothesized that subjects would primarily decrease soleus activity due to its synergistic mechanics with the exoskeleton. ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261095 Sat, 14 Feb 2009 05:00:00 +0100 2261095 http://www.medworm.com/index.php?rid=2261094&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4668434 This study showed that CLME ensures stable gait. In a second study, to be presented in this paper, healthy subjects walk with both their own legs to assess the interference with self-determined walking. Evaluation criteria are: Power delivered to the joints by the robot, electromyography (EMG) distortions, and kinematic distortions, all compared to zero torque control, which is the baseline of minimum achievable interference. Results indicate that interference of the robot is lower with CLME than with a fixed reference trajectory, mainly in terms of lowered exchanged power and less alteration of EMG. This implies that subjects can walk more naturally with CLME, and they are assisted less by the robot when it is not needed. Future studies with patients are yet to show whether these properti... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261094 Sat, 14 Feb 2009 05:00:00 +0100 2261094 http://www.medworm.com/index.php?rid=2261093&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4668435 Visual biofeedback with information about the patients' degree of activity is a valuable adjunct to robot-assisted gait training as means of increasing the motivation and participation of the patients during highly repetitive training sessions. In the driven gait orthosis (DGO) Lokomat, an estimation of the patient's activity level was based on man–machine interaction forces as measured at the hip and knee actuators of the exoskeletal device. In an early approach, theoretical assumptions about the expected man–machine interaction forces, due to the varying behavior of the patients, were formulated for the calculation of quantitative biofeedback. In contrast to this theory-based approach, we have developed a novel method where the biofeedback calculations were based on measure... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261093 Sat, 14 Feb 2009 05:00:00 +0100 2261093 http://www.medworm.com/index.php?rid=2261092&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4703286 This study presents a method that can be used by clinicians facing the challenge of prescribing and assessing walking aids to restore the locomotion of lower limb amputees in the framework of an evidence-based practice. (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=2261092 Sat, 14 Feb 2009 05:00:00 +0100 2261092 http://www.medworm.com/index.php?rid=2261091&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4663875 Gait training of stroke survivors is crucial to facilitate neuromuscular plasticity needed for improvements in functional walking ability. Robot assisted gait training (RAGT) was developed for stroke survivors using active leg exoskeleton (ALEX) and a force-field controller, which uses assist-as-needed paradigm for rehabilitation. In this paradigm undesirable gait motion is resisted and assistance is provided towards desired motion. The force-field controller achieves this paradigm by effectively applying forces at the ankle of the subject through actuators on the hip and knee joints. Two stroke survivors participated in a 15-session gait training study each with ALEX. The results show that by the end of the training the gait pattern of the patients improved and became closer to a healthy ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2261091 Sat, 14 Feb 2009 05:00:00 +0100 2261091 http://www.medworm.com/index.php?rid=2261090&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4782187 The six contributed papers in this special issue focus on the theme of lower extremity exoskeletons for gait rehabilitation. (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=2261090 Sat, 14 Feb 2009 05:00:00 +0100 2261090 http://www.medworm.com/index.php?rid=2261089&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4782184 (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=2261089 Sat, 14 Feb 2009 05:00:00 +0100 2261089 http://www.medworm.com/index.php?rid=2261088&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4782182%26arnumber%3D4782186 (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=2261088 Sat, 14 Feb 2009 05:00:00 +0100 2261088 http://www.medworm.com/index.php?rid=2184399&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4536579 Despite growing interest in applying machine learning to neuroimaging analyses, few studies have gone beyond classifying sensory input to directly predicting behavioral output. With spatial resolution on the order of millimeters and temporal resolution on the order of seconds, functional magnetic resonance imaging (fMRI) is a promising technology for such applications. However, fMRI data's low signal-to-noise ratio, high dimensionality, and extensive spatiotemporal correlations present formidable analytic challenges. Here, we apply different machine-learning algorithms to previously acquired data to examine the ability of fMRI activation in three regions—the nucleus accumbens (NAcc), medial prefrontal cortex (MPFC), and insula—to predict purchasing. Our goal was to improve sp... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2184399 Sun, 14 Dec 2008 05:00:00 +0100 2184399 http://www.medworm.com/index.php?rid=2102117&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4747402 (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=2102117 Sun, 14 Dec 2008 05:00:00 +0100 2102117 http://www.medworm.com/index.php?rid=2102116&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4747404 (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=2102116 Sun, 14 Dec 2008 05:00:00 +0100 2102116 http://www.medworm.com/index.php?rid=2102115&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4747401 (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=2102115 Sun, 14 Dec 2008 05:00:00 +0100 2102115 http://www.medworm.com/index.php?rid=2102114&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4747504 (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=2102114 Sun, 14 Dec 2008 05:00:00 +0100 2102114 http://www.medworm.com/index.php?rid=2102113&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4747400 (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=2102113 Sun, 14 Dec 2008 05:00:00 +0100 2102113 http://www.medworm.com/index.php?rid=2102112&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4747405 (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=2102112 Sun, 14 Dec 2008 05:00:00 +0100 2102112 http://www.medworm.com/index.php?rid=2102111&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4599231 Visually impaired people are often discouraged in using electronic aids due to complexity of operation, large amount of training, nonoptimized degree of information provided to the user, and high cost. In this paper, a new multisensor architecture is discussed, which would help blind people to perform urban mobility tasks. The device is based on a multisensor strategy and adopts smart signal processing. (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=2102111 Sun, 14 Dec 2008 05:00:00 +0100 2102111 http://www.medworm.com/index.php?rid=2102110&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4731273 We have developed a robotic interface to train hand and finger function. HandCARE is a Cable-Actuated REhabilitation system, in which each finger is attached to an instrumented cable loop allowing force control and a predominantly linear displacement. The device, whose designed is based on biomechanical measurements, can assist the subject in opening and closing movements and can be adapted to accommodate various hand shapes and finger sizes. Main features of the interface include a differential sensing system, and a clutch system which allows independent movement of the five fingers with only one actuator. The device is safe, easily transportable, and offers multiple training possibilities. This paper presents the biomechanical measurements carried out to determine the requirements for a ... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2102110 Sun, 14 Dec 2008 05:00:00 +0100 2102110 http://www.medworm.com/index.php?rid=2102109&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4731275 This study evaluated the effects of fascicle perineurial thickness, diameter, and position on axonal excitation thresholds and population recruitment using finite element models and NEURON simulations. The perineurial thickness of human fascicles was found to be 3.0% $pm$ 1.0% of the fascicle diameter. Increased perineurial thickness and fascicle diameter increased activation thresholds. The presence of a large neighboring fascicle caused a significant change in activation of a smaller target fascicle by as much as 80% $pm$ 11% of the total axon population. Smaller fascicles were recruited at lower amplitudes than neighboring larger fascicles. These effects were further illustrated in a realistic model of a human femoral nerve surrounded by a nerve cuff electrode. The data suggest that fas... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2102109 Sun, 14 Dec 2008 05:00:00 +0100 2102109 http://www.medworm.com/index.php?rid=2102108&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4731274 The basic reciprocity between individual parts and collective organization constitutes a key scientific question spanning the biological and social sciences. Such reciprocity is accompanied by the absence of direct linkages between levels of description giving rise to what is often referred to as the aggregation or nonequivalence problem between levels of analysis. This issue is encountered both in neuroscience and economics. So far, in spite of being identified and extensively discussed in various (other) scientific fields, the problem of understanding the nature of the interactions and coordination dynamics between individual (neuron $sim$ agent) and collective (neural networks $sim$ population of humans) behaviors has received little, if any attention in the growing field of neuroeconom... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2102108 Sun, 14 Dec 2008 05:00:00 +0100 2102108 http://www.medworm.com/index.php?rid=2102107&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4537154 This study aims to characterize the electroencephalography (EEG) correlates of exploratory behavior. Decision making in an uncertain environment raises a conflict between two opposing needs: gathering information about the environment and exploiting this knowledge in order to optimize the decision. Exploratory behavior has already been studied using functional magnetic resonance imaging (fMRI). Based on a usual paradigm in reinforcement learning, this study has shown bilateral activation in the frontal and parietal cortex. To our knowledge, no previous study has been done on it using EEG. The study of the exploratory behavior using EEG signals raises two difficulties. First, the labels of trial as exploitation or exploration cannot be directly derived from the subject action. In order to a... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2102107 Sun, 14 Dec 2008 05:00:00 +0100 2102107 http://www.medworm.com/index.php?rid=2102106&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4685630 Recently, a rapidly growing approach within consumer research has developed under the label of “consumer neuroscience.” Its goal is to use insights and methods from neuroscience to enhance the understanding of consumer behavior. In this paper we aim to provide an overview of questions of interest to consumer researchers, to present initial research findings, and to outline potential implications for consumer research. In order to do so, we first discuss the term “consumer neuroscience” and give a brief description of recently discussed issues in consumer research. We then provide a review and short description of initial empirical evidence from past studies in consumer neuroscience. Next, we present an example of how consumer research or, more specifically, cust... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2102106 Sun, 14 Dec 2008 05:00:00 +0100 2102106 http://www.medworm.com/index.php?rid=2102105&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4685627 We investigated brain activity during the observation of TV commercials by tracking the cortical activity and the functional connectivity changes in normal subjects. The aim was to elucidate if the TV commercials that were remembered by the subjects several days after their first observation elicited particular brain activity and connectivity compared with those generated during the observation of TV commercials that were quickly forgotten. High-resolution electroencephalogram (EEG) recordings were performed in a group of healthy subjects and the cortical activity during the observation of TV commercials was evaluated in several regions of interest coincident with the Brodmann areas (BAs). The patterns of cortical connectivity were obtained in the four principal frequency bands, Theta (3&#... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=2102105 Sun, 14 Dec 2008 05:00:00 +0100 2102105 http://www.medworm.com/index.php?rid=2102104&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4731272 The five papers in this special section are devoted to the topic of neuroeconomics. (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=2102104 Sun, 14 Dec 2008 05:00:00 +0100 2102104 http://www.medworm.com/index.php?rid=2102103&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4731271%26arnumber%3D4747403 (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=2102103 Sun, 14 Dec 2008 05:00:00 +0100 2102103 http://www.medworm.com/index.php?rid=1931040&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4666775 (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=1931040 Sat, 04 Oct 2008 04:00:00 +0100 1931040 http://www.medworm.com/index.php?rid=1931039&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4666774 (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=1931039 Sat, 04 Oct 2008 04:00:00 +0100 1931039 http://www.medworm.com/index.php?rid=1931038&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4595651 Virtual scanning keyboards are commonly used augmentative communication aids by persons with severe speech and motion impairments. Designers of virtual scanning keyboards face problems in evaluating alternate designs and hence in choosing the better design among alternatives. Automatic evaluation of designs will be helpful to designers in making the appropriate design choice. In this paper, we present performance models for virtual scanning keyboards that can be used for automatic evaluation. The proposed models address the limitations present in the reported work on similar models. We compared the model predictions with results from user trials and established the validity of the proposed models. (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=1931038 Sat, 04 Oct 2008 04:00:00 +0100 1931038 http://www.medworm.com/index.php?rid=1931037&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4595647 A technique is described for correcting for subject movement while imaging the residual limb of a person with a transtibial amputation. Small reflective markers were placed on the residual limb, and then their motions tracked during scanning using two stationary cameras. The marker position measurements were used to generate appropriate translational and rotational transformation matrices so that limb motion could be corrected for during the 1.5-s scan interval. Evaluation tests showed good performance for moderate (2–4 mm) to high (5–8 mm) motion cases. The difference in mean absolute cross-sectional area between the test scan and a stationary reference scan was reduced by approximately one half when motion correction was used compared with when motion correction was not use... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931037 Sat, 04 Oct 2008 04:00:00 +0100 1931037 http://www.medworm.com/index.php?rid=1931036&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4595652 We have developed a noninvasive, unobtrusive magnetic wireless tongue-computer interface, called “Tongue Drive,” to provide people with severe disabilities with flexible and effective computer access and environment control. A small permanent magnet secured on the tongue by implantation, piercing, or tissue adhesives, is utilized as a tracer to track the tongue movements. The magnetic field variations inside and around the mouth due to the tongue movements are detected by a pair of three-axial linear magneto-inductive sensor modules mounted bilaterally on a headset near the user's cheeks. After being wirelessly transmitted to a portable computer, the sensor output signals are processed by a differential field cancellation algorithm to eliminate the external magnetic field int... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931036 Sat, 04 Oct 2008 04:00:00 +0100 1931036 http://www.medworm.com/index.php?rid=1931035&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4627455 We investigated the performance of three user interfaces for restoration of cursor control in individuals with tetraplegia: head orientation, electromyography (EMG) from face and neck muscles, and a standard computer mouse (for comparison). Subjects engaged in a 2-D, center-out, Fitts' Law style task and performance was evaluated using several measures. Overall, head orientation commanded motion resembled mouse commanded cursor motion (smooth, accurate movements to all targets), although with somewhat lower performance. EMG commanded movements exhibited a higher average speed, but other performance measures were lower, particularly for diagonal targets. Compared to head orientation, EMG as a cursor command source was less accurate, was more affected by target direction and was more prone t... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931035 Sat, 04 Oct 2008 04:00:00 +0100 1931035 http://www.medworm.com/index.php?rid=1931034&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4595648 Accelerometry has the potential to measure balance, defined as high-frequency body sway, ambulatorily in a simple and inexpensive way. The aim of this study was to determine and compare the sensitivity of accelerometric balance parameters during the sit-to-stand (STS) movement. Eleven healthy subjects (four males, $28.2 pm 7.9$ years) and 31 patients with stroke (21 males; $63.3pm 12.8$ years) were included. The healthy subjects performed STS movements in four conditions with different levels of difficulty. Data of the patients were compared 1) with healthy subjects, 2) between patient subgroups, and 3) between different phases of recovery to assess the sensitivity of accelerometry for differences in balance control. Accelerometers were attached to the trunk, and force plate measurements w... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931034 Sat, 04 Oct 2008 04:00:00 +0100 1931034 http://www.medworm.com/index.php?rid=1931033&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4595646 This paper describes the performance of a 16-channel implanted neuroprosthesis for standing and transfers after spinal cord injury including four-contact nerve-cuff electrodes stimulating the femoral nerve for knee extension. Responses of the nerve-cuffs were stable and standing times increased by 600% over time-matched values with a similar eight-channel neuroprosthesis utilizing muscle-based electrodes on vastus lateralis for knee extension. (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=1931033 Sat, 04 Oct 2008 04:00:00 +0100 1931033 http://www.medworm.com/index.php?rid=1931032&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4633628 Significant strides have been recently made to develop highly sensorized cybernetic prostheses aimed at restoring sensorimotor limb functions to those who have lost them because of a traumatic event (amputation). In these cases, one of the main goals is to create a bidirectional link between the artificial devices (e.g., robotic hands, arms, or legs) and the nervous system. Several human–machine interfaces (HMIs) are currently used to this aim. Among them, interfaces with the peripheral nervous system and in particular longitudinal intrafascicular electrodes can be a promising solution able to improve the current situation. In this paper, the potentials and limits of the use of this interface to control robotic devices are presented. Specific information is provided on: 1) the neuro... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931032 Sat, 04 Oct 2008 04:00:00 +0100 1931032 http://www.medworm.com/index.php?rid=1931031&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4627452 The extraction of the salient characteristics from brain connectivity patterns is an open challenging topic since often the estimated cerebral networks have a relative large size and complex structure. Since a graph is a mathematical representation of a network, which is essentially reduced to nodes and connections between them, the use of a theoretical graph approach would extract significant information from the functional brain networks estimated through different neuroimaging techniques. The present work intends to support the development of the “brain network analysis:” a mathematical tool consisting in a body of indexes based on the graph theory able to improve the comprehension of the complex interactions within the brain. In the present work, we applied for demonstrat... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931031 Sat, 04 Oct 2008 04:00:00 +0100 1931031 http://www.medworm.com/index.php?rid=1931030&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4595650 We report the design and performance of a brain–computer interface (BCI) system for real-time single-trial binary classification of viewed images based on participant-specific dynamic brain response signatures in high-density (128-channel) electroencephalographic (EEG) data acquired during a rapid serial visual presentation (RSVP) task. Image clips were selected from a broad area image and presented in rapid succession (12/s) in 4.1-s bursts. Participants indicated by subsequent button press whether or not each burst of images included a target airplane feature. Image clip creation and search path selection were designed to maximize user comfort and maintain user awareness of spatial context. Independent component analysis (ICA) was used to extract a set of independent source time-c... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931030 Sat, 04 Oct 2008 04:00:00 +0100 1931030 http://www.medworm.com/index.php?rid=1931029&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4595649 It is of wide interest to study the brain activity that correlates to the control of brain–computer interface (BCI). In the present study, we have developed an approach to image the cortical rhythmic modulation associated with motor imagery using minimum-norm estimates in the frequency domain (MNEFD). The distribution of cortical sources of mu activity during online control of BCI was obtained with the MNEFD. Contralateral decrease (event-related desynchronization) and ipsilateral increase (event-related synchronization) are localized in the sensorimotor cortex during online control of BCI in a group of human subjects. Statistical source analysis revealed that maximum correlation with movement imagination is localized in sensorimotor cortex. (Source: IEE Transactions on Neural Syste... IEE Transactions on Neural Systems and Rehabilitation Engineering journals http://www.medworm.com/rss/comments.php?id=1931029 Sat, 04 Oct 2008 04:00:00 +0100 1931029 http://www.medworm.com/index.php?rid=1931028&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4666776 (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=1931028 Sat, 04 Oct 2008 04:00:00 +0100 1931028 http://www.medworm.com/index.php?rid=1931027&cid=s_37229_168_f&fid=37229&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Fisnumber%3D4666773%26arnumber%3D4666778 (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=1931027 Sat, 04 Oct 2008 04:00:00 +0100 1931027