An experimental study of the motor theory of consciousness. III. Action-current responses in deaf-mutes during sleep, sensory stimulation and dreams.

Abstract

Photographs were taken of action currents in the muscles of the arm of sleeping deaf mutes. The recording system consisted of microvolt-sensitive amplifiers in connection with string galvanometers. The transition from the waking to the sleep state was accompanied by a progressive diminution in frequency of action currents in the peripheral musculature. A complete absence of action currents during sleep, however, was found in only a small proportion of the cases. It was noted that external stimuli applied during sleep tended to evoke action currents in the peripheral musculature. The onset of dreams could be detected in most instances by the appearance of large action-current responses in the arm and finger muscles.