APA Dictionary of Psychology

a tactile perceptual disorder characterized by an inability to recognize one’s own hand, usually the left. Individuals may be able to write with the left hand but do not believe the writing is their own or, when clasping the two hands, may be unable to acknowledge the left hand as their own without visual clues. The disorder is caused by a defect of the corpus callosum of the brain. It is similar to, and is often considered a synonym for, alien hand syndrome.