THE SAMPLE OF 64 INMATES WAS DIVIDED INTO GROUPS ON THE BASIS OF SOCIALIZATION SCALE RATINGS OF PSYCHOPATHY FROM THE CALIFORNIA PSYCHOLOGICAL INVENTORY. THE GROUPS WERE PRESENTED WITH A RANDOM SERIES OF FAST AND SLOW RISE-TIME AUDITORY TONES RANGING IN INTENSITY FROM 80 TO 120DB. A BECKMAN TYPE R DYNOGRAPH WAS USED TO RECORD BILATERAL PALMAR SKIN CONDUCTANCE; HEART RATE, RESPIRATION AND VALOMETER ACTIVITY WERE MONITORED, AND AUDITORY STIMULI WERE PRODUCED BY AN AUDIO OSCILLATOR. BOTH TESTS WERE CONDUCTED UNDER DOUBLE-BLIND CONDITIONS. RESULTS SHOW THAT THE GROUP CONSIDERED TO BE MOST PSYCHOPATHIC GAVE SMALLER SKIN CONDUCTANCE RESPONSES THAN DID THE OTHER GROUPS, BUT ONLY TO THE 120DB TONES. THESE FINDINGS ARE CONSISTENT WITH THE HYPOTHESIS THAT PSYCHOPATHS ARE ELECTRODERMALLY HYPORESPONSIVE TO INTENSE NONSIGNAL RESPONSE. HIGH RATINGS OF PSYCHOPATHY WERE ASSOCIATED WITH SLOW RECOVERY OF THE SKIN CONDUCTANCE RESPONSE, BUT ONLY WITH THE 120DB FAST RISE-TIME TONES, AND ONLY IN THE LEFT HAND. STUDY DATA AND REFERENCES ARE PROVIDED. (AUTHOR ABSTRACT MODIFIED--DAG)