STUDIES IN STUTTERING: V. A STUDY OF SIMULTANEOUS ANTITROPIC MOVEMENTS OF THE HANDS OF STUTTERERS

A previous study1 of this series showed that right-handed stutterers differed strikingly from right-handed normal speakers in the precedence of the action currents in the forearms during simultaneous voluntary flexion of the digits. These observations led us to make a study of the time of initiation of simultaneous antitropic movements of the hands in the two groups. We attempted to determine whether both hands start to move at exactly the same instant when the subject attempts to move them at the same time but in opposite directions. This apposition of direction was chosen in order to make use of the similarity of opposite movements which results from strict antitropism, that is, right and left pairing of the neuromuscular mechanisms. TECHNIC To record the movements of the two hands, we used a high speed kymograph. The drum revolved about a horizontal axis and carried a paper 8 feet (243.86 cm.)