Heart rate responsivity to a high intensity auditory stimulus: a comparison of male alcoholics and normal controls

Previous research has demonstrated the presence of two heart rate acceleration responses to high intensity auditory stimuli. Both responses, the short latency acceleration peaking at 3-4 beats poststimulus and the long latency acceleration peaking at approximately 30-35 sec poststimulus, have been related to defensive responding to aversive stimuli and thus were employed to examine a stress-related hypothesis of alcoholism. A group of male alcoholics (n = 15) and a group of male controls (m = 15) received a 100 dB tone while heart rate was recorded. While both groups exhibited equal amplitudes on the short latency component, alcoholics exhibited a slower initial response time and relative to normal controls, failed to exhibit a secondary acceleration response. The results are discussed with respect to previous findings of hypo-responsivity observed in alcoholics.