Hand dominance and the modification of the acoustically elicited startle response by a vibrotactile prepulse

Abstract

The acoustic startle eyeblink was measured in 10 right-handed and 10 left-handed college students, in response to an 85-dB SPL, 50-msec broadband noise burst preceded on some trials by either a 50- or a 250-Hz vibrotactile prepulse to the hand (20 msec duration, 20 dB SL, 50-msec onset-to-onset interval). Eyeblink amplitude and latency were generally facilitated by the prepulses, and latency was shorter when prepulses were presented to the dominant rather than the nondominant hand. Responding was more probable in the no-prepulse condition when subjects had the dominant hand in position to receive the prepulses. All subjects responded equally often when prepulses were applied to the dominant hand, but right-handers responded less often than left-handers when prepulses were applied to the nondominant hand. Females responded more often than males in the prepulse conditions, and vibrotactile thresholds were lower in females than in males. © 1991, Psychonomic Society, Inc.. All rights reserved.