Effects of Stress on Motor Performance and Learning

Abstract

Male college students were tested on a motor learning task that involved balancing for 12 trials on the pivoted platform of a stabilometer. The task was made easy for 40 of the subjects by placing the platform 10 in. below the pivot and made difficult for 80 of the subjects by placing it 10 in. above the pivot. Half of the easy task subjects were given electric shocks irregularly during the learning period to produce tension. Their performance or learning did not differ appreciably from the control subjects. Under the same conditions, except that difficult task was used, the experimental subjects achieved the same amount of learning as the controls but showed poorer performance throughout the test. When the application of the tension-producing shock was delayed until the third trial, it produced a lesser amount of performance impairment for that trial but full impairment for later trials. The results support the hypothesis (based on earlier studies) that increased tension impairs performance of a difficult motor task and that rate of learning is independent of the state of tension for either difficult or easy skills—except that predicted better performance under tension for the easy task did not occur.