Veterans are at higher risk than non-Veterans of falling ill with amyotrophic lateral sclerosis (ALS). ALS causes degeneration of motor neurons in both the brain and the spinal cord. Evidence from studies in people with spinal cord injury suggests that activating spared nerve circuits with electromagnetic stimulation improves nerve transmission. With this goal, the investigators have developed a novel method of noninvasive cervical (neck) electrical stimulation (CES). In this study, the investigators will investigate CES for its potential to strengthen nerve circuits to the hands in ALS. To the investigators' knowledge, electrical spinal stimulation for ALS has never been tested previously. This study will be performed in two stages: First, basic experiments will be performed to better understand how CES interacts with other types of electrical and magnetic stimulations over the brain and peripheral nerves. Second, experiments will be performed to determine the types of CES that can facilitate active arm and hand movements. These experiments will improve understanding of electrical stimulation in ALS, and may set the table for future treatments. Both United States Veterans and non-Veterans are eligible to participate in this study.