Brain–computer interfaces (BCIs) enable users to control devices with electroencephalographic (EEG) activity from the scalp or single-neuron within brain. Both methods have disadvantages: EEG has limited resolution and requires extensive training, while recording entails significant clinical risks stability. We demonstrate here for first time that electrocorticographic (ECoG) recorded surface of brain can a one-dimensional computer cursor rapidly accurately. identified ECoG signals were...

The motor cortical substrate associated with reaching was studied as monkeys moved their hands from a central position to one of eight targets spaced around circle. Single-cell activity patterns were recorded in the proximal arm area cortex during task. In addition well-studied average directional selectivity ("preferred direction") single-cell activity, we also found time-varying speed movement be represented activity. A single equation relating discharge rate these two parameters...

In the first large study of its kind, we quantified changes in electrocorticographic signals associated with motor movement across 22 subjects subdural electrode arrays placed for identification seizure foci. Patients underwent a 5–7 d monitoring period array placement, before focus resection, and during this time they participated study. An interval-based motor-repetition task produced consistent quantifiable spectral shifts that were mapped on Talairach-standardized template cortex. Maps...

Signals from the brain could provide a non-muscular communication and control system, brain–computer interface (BCI), for people who are severely paralyzed. A common BCI research strategy begins by decoding kinematic parameters signals recorded during actual arm movement. It has been assumed that these can be derived accurately only intracortical microelectrodes, but long-term stability of such electrodes is uncertain. The present study disproves this widespread assumption showing in humans...

We show here that a brain–computer interface (BCI) using electrocorticographic activity (ECoG) and imagined or overt motor tasks enables humans to control computer cursor in two dimensions. Over brief training period of 12–36 min, each five human subjects acquired substantial particular ECoG features recorded from several locations over the same hemisphere, achieved average success rates 53–73% two-dimensional four-target center-out task which chance accuracy was 25%. Our results support...

Brain-computer interface (BCI) technology aims to help individuals with disability control assistive devices and reanimate paralyzed limbs. Our study investigated the feasibility of an electrocorticography (ECoG)-based BCI system in individual tetraplegia caused by C4 level spinal cord injury. ECoG signals were recorded a high-density 32-electrode grid over hand arm area left sensorimotor cortex. The participant was able voluntarily activate his cortex using attempted movements, distinct...

We have prepared conductive core-sheath nanofibers via a combination of electrospinning and aqueous polymerization. Specifically, electrospun from poly(ε-caprolactone) (PCL) poly((L)-lactide) (PLA) were employed as templates to generate uniform sheaths polypyrrole (PPy) in situ These offer unique system for studying the synergistic effect different cues on neurite outgrowth vitro. found that explanted dorsal root ganglia (DRG) adhered well generated neurites across surface when there was...

There are few effective therapies to achieve functional recovery from motor-related disabilities affecting the upper limb after stroke. This feasibility study tested whether a powered exoskeleton driven by brain-computer interface (BCI), using neural activity unaffected cortical hemisphere, could affect motor in chronic hemiparetic stroke survivors. novel system was designed and configured for home-based setting test of BCI-driven neurorehabilitation outpatient environments.Ten survivors...

Activity was recorded extracellularly from single cells in motor and premotor cortex as monkeys traced figure-eights on a touch-sensitive computer monitor using the index finger. Each unit individually, responses collected four hemispheres (3 primary 1 dorsal premotor) were analyzed population. Population vectors constructed this activity accurately isomorphically represented shape of drawn figures showing that they represent spatial aspect task well. These observations extended by examining...

A bi-directional neural interface (NI) system was designed and prototyped by incorporating a novel recording processing subsystem into commercial stimulator architecture. The NI prototype leverages the infrastructure from an existing neurostimulator to ensure reliable operation in chronic implantation environment. In addition providing predicate therapy capabilities, device adds key elements facilitate research, such as four channels of electrocortigram/local field potential amplification...

This study examines motor cortical representation of hand position and its relationship to the velocity during reaching movements. In all, 978 neurons were recorded from proximal arm area rostral cortex. The results demonstrate that are simultaneously encoded by single in an additive fashion relative weights signals change dynamically reaching. two variables--hand velocity--are highly correlated standard center-out task. A new task (standard reaching) is introduced minimize these...

Recent advancement in electrocorticography (ECoG)-based brain-computer interface technology has sparked a new interest providing somatosensory feedback using ECoG electrodes, i.e., cortical surface electrodes. We conducted 28-day study of stimulation an individual with arm paralysis due to brachial plexus injury examine the sensation produced by electrical cortex. A high-density grid was implanted over and motor cortices. Stimulation through electrodes cortex successfully elicited hand...

Single-unit activity in area M1 was recorded awake, behaving monkeys during a three-dimensional (3D) reaching task performed virtual reality environment. This study compares motor cortical discharge rate to both the hand's velocity and arm's joint angular velocities. Hand is considered parameter of extrinsic space because it measured Cartesian coordinate system monkey's workspace. Joint intrinsic relative adjacent arm/body segments. In initial analysis, as difference hand position or posture...

A motor illusion was created to separate human subjects' perception of arm movement from their actual during figure drawing. Trajectories constructed cortical activity recorded in monkeys performing the same task showed that represented primary cortex, whereas visualized, presumably perceived, trajectories were found ventral premotor cortex. Perception and action representations can be differentially recognized brain may contained structures.

Monkeys traced spirals on a planar surface as unitary activity was recorded from either premotor or primary motor cortex. Using the population vector algorithm, hand's trajectory could be accurately visualized with cortical throughout task. The time interval between this prediction and corresponding movement varied linearly instantaneous radius of curvature; longer when path finger more curved (smaller radius). intervals in cortex fell into two groups, whereas those formed single group. This...

In this paper, intracortical local field potentials (LFPs) and single units were recorded from the motor cortices of monkeys (Macaca fascicularis) while they preformed a standard three-dimensional (3-D) center-out reaching task. During task, subjects held their hands at location central target then reached to one eight peripheral targets forming corners virtual cube. The spectral amplitudes LFPs calculated, with high-frequency LFP (HF-LFP) defined as average amplitude change baseline 60 200...

In this study human motor cortical activity was recorded with a customized micro-ECoG grid during individual finger movements.The quality of the neural signals characterized in frequency domain from three different perspectives: (1) coherence between electrodes, (2) modulation by movement, and (3) accuracy movement decoding.It found that, for high band , neighboring electrodes 0.3.In addition,

Glial-derived neurotrophic factor (GDNF) and nerve growth (NGF) have both been shown to enhance peripheral regeneration following injury target different neuronal populations. The delivery of either at the site may, therefore, result in quantitative differences motor functional recovery. In this study we evaluated effect affinity-based GDNF or NGF from fibrin-filled guidance conduits (NGCs) on recovery a 13 mm rat sciatic defect. Seven experimental groups were consisting system (DS) within...

Brain-computer interface (BCI) technology decodes neural signals in real time to control external devices. In this study, chronic epidural micro-electrocorticographic recordings were performed over primary motor (M1) and dorsal premotor (PMd) cortex of three macaque monkeys. The differential gamma-band amplitude (75-105 Hz) from two arbitrarily chosen 300 μm electrodes (one located each cortical area) was used for closed-loop a one-dimensional BCI device. Each monkey rapidly learned period...