Shock therapy? electrical pulses aim to restore movement in paralysis

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Healthy Volunteer Inclusion Criteria: * Individuals between 18 and 75 years of age * Individuals without physical disabilities or conditions/diseases that may make them incapable of completing the physical study tasks or otherwise places them at a greater risk of harm * Individuals that are considered English Proficient due to the study requirements to follow verbal commands during sessions * Individuals that are able to comprehend the study goals and procedures, and are able to provide informed consent for participation * Individuals that are willing and able to visit the study center for study procedures, which may be up to 5 sessions a week for up to 1 year (at least 2 months) at up to 4 hours per session Stroke and Spinal Cord Injury Participant Inclusion Criteria: * Individuals between 18 and 75 years of age * Individuals with a limited ability to use at least one hand due to a spinal cord injury or stroke * Individuals that are at least six months from their initial stroke or one year from their initial spinal cord injury * Individuals that are considered English Proficient due to the study requirements to follow verbal commands during testing sessions * Individuals that are able to comprehend the study goals and procedures, and are able to provide informed consent for participation * Individuals that are willing and able to visit the study center for study procedures, which may be up to 5 sessions a week for up to 1 year (at least 2 months) at up to 4 hours per session Brain or Nerve Injury Participant Inclusion Criteria: * Individuals between 18 and 75 years of age * Individuals with a limited ability or no ability to use at least one limb due to a brain or nerve injury such as a traumatic brain injury, brachial plexus injury, peripheral nerve damage, or Parkinson's Disease. * Individuals that are considered English Proficient due to the study requirements to follow verbal commands during testing sessions * Individuals that are able to comprehend the study goals and procedures, and are able to provide informed consent for participation * Individuals that are willing and able to visit the study center for study procedures, which may be up to 5 sessions a week for up to 1 year (at least 2 months) at up to 4 hours per session Exclusion Criteria for All Study Participants: * Individuals participating in another study that may affect the conduct or results of this study * Individuals having or exhibiting any of the following, as specified by self-report: * Stage III-IV pressure ulcers that adversely interfere with study involvement (i.e., pressure ulcer on the extremity of interest or prohibits extended bouts of sitting) * History of epilepsy * Chronically-implanted electronic medical device (e.g. deep brain stimulator, epidural stimulator, cardiac pacemaker, vagus nerve stimulator, or other) * Abnormalities of the arms/hands, legs/feet, or spinal column that would prevent electrical stimulation * Ventilator dependence * History of serious mood or thought disorder * Uncontrolled autonomic dysreflexia * Severe spasticity in extremities of interest that are uncontrolled by pharmacological methods or prevents electrical stimulation * Botulinum toxin injections to the extremity of interest within 3 months * Presence of active cancer at or near the areas of transcutaneous stimulation * History of heart or kidney disease * History of additional neurologic diseases (e.g., multiple strokes, multiple sclerosis, etc.) * Presence of other serious infections, diseases, or disorders that could affect ability to participate in this study (e.g., uncontrolled hypertension, uncontrolled diabetes, rheumatic disease, peripheral neuropathy, HIV or AIDS, etc.) * Individuals with a substance abuse (alcoholism or other) problem * Pregnant women * Prisoners