Pharmacological Agents for Chronic Spinal Cord Injury (SCI)

Inclusion Criteria: * Male or female between 18 and 65 years of age; clinically stable chronic (\> 12 months) SCI at or above C8 spinal segment; * Motor-incomplete with a score of 2 or more (out of 5) on manual muscle testing (MMT) of finger extension, finger flexion, or finger abduction in left or right hand(s); or able to perform thumb-index finger pinch of the left or right hand; * Detectable stimulation-evoked muscle responses of the left or right first dorsal interosseous (FDI) and/or abductor pollicis brevis (APB); Detectable FDI/APB surface electromyography (EMG) muscle activity during thumb-index finger pinch; * Must have stable: medication \[≥ 30 days prior\]; rehabilitation regimen \[≥ 15 days prior\]; * Must be able to: abstain from alcohol, smoking and caffeine consumption on the day prior/of each experiment; abstain from recreational drugs for the entirety of the study; commit to study requirements (i.e., 7 visits); provide informed consent. Exclusion Criteria: * History of moderate or severe head trauma (loss of consciousness for greater than one hour or evidence of brain contusion or hemorrhage or depressed skull fracture on prior imaging); * History of other serious central or peripheral neurological injury; * History of implanted brain/spine/nerve stimulators, aneurysm clips, ferromagnetic metallic implants in the head (except inside mouth); cochlear implants; cardiac pacemaker/defibrillator; intracardiac lines; currently increased intracranial pressure; o…