Changes in muscular tension during learning.

Abstract

The relationship between progress in sensorimotor learning (mirror drawing) and muscular tension were studied. Time and errors were taken as criteria of learning. Force exerted by the writing hand on a pneumatic stylus was the measure of muscular tension. One hundred trials were made by each of 25 subjects at the rate of fifteen runs per day. Nine subjects made a series of "fatigue" runs following the completion of the original one hundred trials. Analysis of the results shows that muscular tension decreases for the first 15-20 trials and then increases regularly as learning progresses. Points of increased difficulty in the tracing pattern are associated with increased muscular tension. Normally the occurrence of an error results in increased tension. Fatigue and excessive motivation increase muscular tension. The results are interpreted as indicating that in the learning process there occurs a reduction in the initially high generalized diffuse tension with a subsequent increased localization of the tension in the muscle groups specifically involved in the performance of the task at hand.