Precision hypothesis and the end-state comfort effect

Abstract

Recently, motor control research has emphasized the planning of macroscopic aspects of control. In object manipulation studies, when participants complete a movement in a comfortable posture, an end-state comfort effect is attained. One explanation for this effect is the precision hypothesis, which states that precision increases when participants are in a comfortable position. This research directly tests the precision hypothesis in two experiments. In Experiment 1, participants picked up a dowel and touched a large or small target on a wall. For the second experiment, the same procedure was followed using a pinpoint target. The probability analyses of the first experiment indicated that the end-state comfort effect was magnified in the small target condition and that the point-of-change effect (Short and Cauraugh, 1997) appeared only when end-state comfort was magnified. Error analyses in Experiment 2 showed that participants were more accurate when in a more comfortable position. The present findings indicate that the precision hypothesis plays a significant role in the end-state comfort effect.