Neuromodulation of the Cortex and Spinal Cord

The participant will undergo a battery of clinical assessments to identify the upper extremity motor performance, sensory acuity, and ability to complete activities of daily living. Tests 1-5 will be completed separately for each hand. All participants will be video recorded while completing these assessments. The recordings will be used for grading tasks and data analysis: Box and Blocks, 9-hold peg board, Test of Arm Selective Control, Sensory Acuity Testing, KINARM End-Point Lab Sensory Test, Section GG of the inpatient Rehabilitaion Facility-Patient Assessment Instrument, NEURO-QOL Upper Extremity Function Scale, Edinburgh Handed Inventory

Resting state, brain-spinal cord activity, spinal cord microstructure, magnetic resonance spectroscopy

Hmax 20-50 stimulations of increasing intensity. Next, the participant will sit quietly as 10 stimulations will be delivered at the participant's Hmax with an interstimulus interval of 15 seconds. Subsequently, stimulations at the participant's Hmax will be applied as the participants produce a contraction of 10-20% of their maximum voluntary contraction (MVC). The target contraction level will be shown in real-time based on the FCR EMG activity. The participant maintains their EMG activity at the target level for 6.5 seconds as 10 stimulations are delivered at the participants Hmax.

Resting state, somatosensory, isometric force matching, entrainment

Cortical stimulation, spinal cord stimulation - sham and stim