An Observation of Jaw Tapping Movement Commanded by Acoustic Signals with Random Interval

Abstract

Conditions of repetitive jaw tapping movements in time to acoustic signals with 1.3 Hz fixed cycle (fixed cycle tapping), in time to acoustic signals with random interval (observation on 1.3Hz parts: random interval tapping), ad lib tappingwere observed. The subjects were 16 healthy dentulous young adults, and their mean age was 25.0 years. They were instructed to make tooth contact close to the signals. Observation was made on the relation among Mm EMG, MKG, and acoustic signal. The results were as follows:
1. In random interval tapping, it was found that the subjects began jaw tapping after they recognized acoustic signals.
2. Though in random interval tapping they could not anticipate time relation, there was proficiency in the movement control by experience in trials. It was considered that the proficiency depended on spatial anticipation of the task.
3.These characteristics in random interval tapping were similar to those in 0.3 Hzfixed cycle jaw tapping. It was confirmed that both tasks hardly depend on anticipation and depended greatly on “an instant performance control”.
4. It was suggested that to remove many influences by anticipation was one of characteristics of 0.3 Hz fixed cycle tapping and that when it was used it had some advantages of diagnosis of movement control of the jaw.