A man with an amputated arm is fitted with a device that reads electrical impulses to help him control an artificial limb. The man sits behind a large mechanical prosthetic arm and uses his abdominal muscles to control the artificial arm with electrical impulses. The arm raises and touches a ball hanging above the device. Another experiment is shown where a man sits in front of a drawing of a human figure and uses muscle contractions to create an electrical current used to turn on corresponding lights on the model.