YOUNG MALE SUBJECTS FROM A PRISON POPULATION WERE DIVIDED INTO GROUPS ACCORDING TO THEIR MINNESOTA MULTIPHASIC PERSONALITY INVENTORY (MMPI) ANXIETY (PD) SCORE AND THEN SUBDIVIDED ON THE BASIS OF MMPI WELSH ANXIETY SCALE (WAS) SCORES. FROM AN INITIAL POOL OF 121, 4 GROUPS OF 16 SUBJECTS WERE FORMED ON THE BASIS OF WHETHER THEY WERE ABOVE OR BELOW THE MEAN ON EACH SCALE. THEN THE 16 SUBJECTS WHO REPRESENTED THE MOST EXTREME VALUES ON BOTH SCALES WERE SELECTED FROM EACH OF THESE 4 GROUPS. FINALLY, EACH OF THESE FOUR GROUPS WAS SUBDIVIDED INTO GROUPS OF EIGHT RANDOMLY-ASSIGNED SUBJECTS PER GROUP TO OBSERVE EIGHT HIGH OR LOW LEVELS OF MODELED STRESS. SUBJECTS IN EACH GROUP OBSERVED A MODEL EXHIBITING EITHER MILD OR SEVERE DISTRESS IN RESPONSE TO ELECTRIC SHOCK. IT WAS HYPOTHESIZED THAT THE DIFFERENT CLINICAL GROUPS WOULD EXHIBIT DIFFERENT PHYSIOLOGICAL EMOTIONAL RESPONSE PATTERNS. PHYSIOLOGICAL RESPONSES OF THE SUBJECTS WERE RECORDED ON A GRASS MODEL-5 POLYGRAPH. RESULTS SHOWED THAT LOW PD SUBJECTS WERE MORE AUTONOMICALLY RESPONSIVE TO AN EMOTIONAL STIMULUS (MODELED DISTRESS) THAN HIGH PD SUBJECTS FROM THE SAME PRISON POPULATION. MOREOVER, HIGH WAS SUBJECTS WERE MORE RESPONSIVE THAN LOW WAS SUBJECTS. THE LEVEL OF DISTRESS EXHIBITED BY THE MODEL HAD NO EFFECT. RESULTS OF THE EXPERIMENT ARE GENERALLY CONSISTENT WITH THE HYPOTHESIS WHICH SUGGESTS THAT PSYCHOPATHS MAY BE CHRONICALLY UNDERREACTIVE SO THAT THEIR AUTONOMIC RESPONSE THRESHOLD IS HIGHER THAN THAT FOR NONPSYCHOPATHS. REFERENCES AND GRAPHIC AND TABULAR DATA ARE PROVIDED. (RCB)