Recovery of Motor Performance following Startle

The present study was designed to provide information concerning the extent to which startle disrupts motor performance, the rate of recovery, and characteristics of Ss who differ in susceptibility to startle. 30 Ss were trained on both reaction time and tracking tasks. Continuous recordings were taken of heart rate and skin conductance. During a subsequent period of continuous tracking, “startle” stimuli (115 db random noise) were unexpectedly presented. Results showed the recovery of tracking performance following startle to be quite rapid; performance returned to pre-stimulus levels within 15 sec. following stimulation. Contrary to several previous studies, reaction times to the startle stimuli decreased relative to nonstartle reaction times. Ss with the greatest increase in tracking error following startle were least proficient prior to startle. There was also an indication that these Ss reacted more strongly to startle, in terms of both their subjective response and heart-rate acceleration, than those Ss whose tracking was least impaired by startle. An apparent covariation between recovery curves for heart rate and tracking error was found following startle.