Journal of Neural Engineering

Restoring sensorimotor function in individuals with severe paralysis remains an important challenge in the field of medicine. Here we show, for the first time, an individual with severe upper-limb sensorimotor impairment can interact with real-world objects through another individual using an implanted brain-computer interface (iBCI) and wireless muscle activation, while also engaging in cooperative rehabilitation. This human avatar paradigm enabled the iBCI study participant to generate motor ...

Intracortical brain-computer interfaces (iBCI) have the potential to restore independence for individuals with significant motor or communication impairments. One of the most realistic avenues for clinical translation of iBCI technology is to enable control of a computer cursor--i.e. movement-related neural activity is interpreted (decoded) and used to drive cursor function. Both nonhuman primate and human studies have demonstrated high-level cursor translation control using attempted upper limb...

Vision and proprioception regulate motor output during reaching. To study the effects of sensory input on motor control, brain computer interfaces (BCIs) offer particular advantages. As part of a long-term clinical BCI trial, we implanted two 96-channel microelectrode arrays into M1 of a person who was completely paralyzed below the neck but retained intact somatosensation. Neural recordings from M1 were transformed into a 2-dimensional velocity control signal for a robotic arm using an optimal ...

This study presents a heterogeneous embedded architecture that addresses a fundamental gap in wearable myoelectric systems: the inability of existing platforms to simultaneously provide high-density signal acquisition, computational flexibility, and autonomy. The platform integrates two 64-channel RHD2164 front-ends (128 channels total) with a Zynq UltraScale+ multiprocessor system-on-chip for heterogeneous processing. A PYNQ-based Python/Linux framework enables scalable algorithm development. E...

Most daily tasks require simultaneous control of both hands. Here we demonstrate simultaneous classification of gestures in both hands using multi-unit activity recorded from bilateral motor and somatosensory cortices of a tetraplegic participant. Attempted gestures were classified using hierarchical linear discriminant models trained separately for each hand. In an online experiment, gestures were continuously classified and used to control two robotic arms in a center-out movement task. Bimanu...

While recent advances in intracortical brain-computer interfaces (iBCI) have demonstrated the ability to restore motor and communication functions, such demonstrations have generally been confined to controlled experimental settings and have required bulky laboratory hardware. Here, we developed and evaluated a self-contained portable iBCI that enabled the user to interact with various computer programs. The iBCI, which weighs 1.5 kg, consists of digital headstages, a small signal processing hub...

Limb loss leads to severe sensorimotor deficits and requires the use of a prosthetic device, especially in lower-limb amputees. While direct recording from residual nerves offers a biomimetic route for an effective prosthetic control, the low amplitude and noisy nature of these neural signals together with the challenge of establishing a reliable nerve interfacing, have hindered its adoption. Intraneural multichannel electrodes could potentially establish an effective interface with the nerve fi...

ObjectiveA major challenge for controlling a prosthetic arm is communication between the device and the users phantom limb. We show the ability to enhance amputees phantom limb perception and improve movement decoding through targeted transcutaneous electrical nerve stimulation (tTENS). ApproachTranscutaneous nerve stimulation experiments were performed with four amputee participants to map phantom limb perception. We measured myoelectric signals during phantom hand movements before and after a...

This study aimed to optimize intracortical microelectrode array implantation sites for grasp-related motor decoding by integrating anatomical, functional, and vascular imaging with preoperative 3D modeling. A participant with C5 tetraplegia underwent anatomical MRI, diffusion-weighted imaging, and task-based fMRI to identify grasp-related cortical regions while avoiding vasculature and speech-critical areas. Quicktome software was used to refine target selection by integrating structural connec...

Haptic feedback can play a useful role in rehabilitation and brain-computer interface applications by providing users with information about their system or performance. One challenge delivering tactile stimulation is not knowing how the haptic sensation is actually perceived, irrespective of the stimulation amplitude, during real-world use and beyond controlled psychophysical experiments. In a participant with chronically implanted electrocorticography arrays, we observed that perceived intensi...

ObjectiveWe developed and validated a detection-guided artifact removal framework for clinical electroencephalography (EEG). It corrects only the contaminated segments and preserves artifact-free data. ApproachThe framework employs convolutional neural network (CNN) detectors trained on the Temple University Hospital (TUH) Artifact Corpus of 150 recordings from 105 patients. For eye movement artifacts (20 second windows), it uses independent component analysis (ICA) and canonical correlation an...

Defining eloquent cortex intraoperatively, traditionally performed by neurosurgeons to preserve patient function, can now help target electrode implantation for restoring function. Brain-machine interfaces (BMIs) have the potential to restore upper-limb motor control to paralyzed patients but require accurate placement of recording and stimulating electrodes to enable functional control of a prosthetic limb. Beyond motor decoding from recording arrays, precise placement of stimulating electrodes...

AO_SCPLOWBSTRACTC_SCPLOWO_ST_ABSObjectiveC_ST_ABSEnable neural control of individual prosthetic fingers for participants with upper-limb paralysis. ApproachTwo tetraplegic participants were each implanted with a 96-channel array in the left posterior parietal cortex (PPC). One of the participants was additionally implanted with a 96-channel array near the hand knob of the left motor cortex (MC). Across tens of sessions, we recorded neural activity while the participants attempted to move indivi...

Neurological diseases and neuropsychiatric disorders are often characterized by abnormal neural oscillations, such as exaggerated synchronization or suppression within a narrow frequency band and complex oscillation coupling which disrupt normal brain function and contribute to debilitating symptoms. Phase-dependent stimulation (PDS) offers a promising solution by synchronizing electrical stimulation with specific phases of neural oscillations, thereby enhancing therapeutic precision and efficac...

Both intracortical microstimulation (ICMS) and peripheral nerve stimulation (PNS) can restore tactile sensation to people living with physical disabilities, such as spinal cord injury (SCI) or amputation. While both techniques have demonstrated success in evoking meaningful sensations in the upper limb, they have only been investigated in separate studies with different patient populations, and thus their perceptual characteristics have never been systematically compared to determine the relativ...

IntroductionDynamic modulation of grip occurs mainly within the major structures of the brain stem, in parallel with cortical control. This basic, but fundamental level of the brain, is robust to ill-formed feedback and to be useful, it may not require all the perceptual information of feedback we are consciously aware. This makes it viable candidate for using peripheral nerve stimulation (PNS), a form of tactile feedback that conveys intensity and location information of touch well but does not...

BackgroundTranscutaneous electrical nerve stimulation (TENS) has been a commonly used modality to relieve aches and pain for over 40 years. Commercially available devices provide multiple therapy modes involving a different combination of frequency and pulse width with intensity. While frequency sets sensation, intensity helps determine tolerability, longer pulse width is reported to induce a feeling of deeper stimulation. In fact, longer pulse width has been empirically shown to deliver current...

Recent advances in deep brain stimulation (DBS) devices have enabled the ability to capture continuous neural recordings concurrently with stimulation therapy in the background of everyday life. These recordings provide the opportunity to investigate neural biomarkers of various behaviors or clinical status. However, they are susceptible to artifacts that can obscure and limit our ability to interpret neural signals. In a cohort of 23 patients who underwent DBS for obsessive-compulsive disorder ...

AO_SCPLOWBSTRACTC_SCPLOWElectrical stimulation of tactile nerve fibers that innervated an amputated hand results in vivid sensations experienced at a specific location on the phantom hand, a phenomenon that can be leveraged to convey tactile feedback through bionic hands. Ideally, electrically evoked tactile sensations would be experienced on the appropriate part of the hand: Touch with the bionic index fingertip, for example, would elicit a sensation experienced on the index fingertip. However,...

PurposeVisual function testing in retinal prosthesis users relies on repetitive psychophysical tasks that are cognitively demanding and fatiguing. Gamification may increase engagement, but its effects on perceptual performance in implanted users remain unclear. MethodsThree Argus II users completed circle localization and motion direction discrimination in clinical and gamified versions. Visual stimuli, trial structure, and response requirements were matched within each participant; gamified ve...