A DELAYED, DIFFERENTIAL PARADIGM WAS USED TO INVESTIGATE ELECTRODERMAL AND VASOMOTOR CONDITIONING IN 54 BRITISH MALE PENITENTIARY INMATES DIVIDED INTO THREE GROUPS--PSYCHOPATHS, NONPSYCHOPATHS, AND BORDERLINE PSYCHOPATHS. THREE TONES, EACH 10 SECONDS LONG, WERE PRESENTED SIXTEEN TIMES EACH IN RANDOM ORDER TO THE GROUPS OF INMATES. ONE TONE WAS ALWAYS FOLLOWED BY A SHOCK, ANOTHER BY A SLIDE OF A NUDE FEMALE, AND THE THIRD WAS ALWAYS PRESENTED ALONE. THE RESULTS INDICATE THAT THE PSYCHOPATHS GAVE VERY LITTLE EVIDENCE OF DIFFERENTIAL ELECTRODERMAL CONDITIONING. HOWEVER, THEY ACQUIRED DIFFERENTIAL CARDIAC AND DIGITAL VASOMOTOR RESPONSES JUST AS READILY AS DID THE NONPSYCHOPATHS BOTH TO THE CONDITIONED STIMULUS FOLLOWED BY SHOCK AND THE CONDITIONED STIMULUS FOLLOWED BY SLIDES. NEITHER GROUP GAVE ANY EVIDENCE OF DIFFERENTIAL CEPHALIC VASOMOTOR CONDITIONING. THE PSYCHOPATHS EXHIBITED LOWER LEVELS OF TONIC ELECTRODERMAL ACTIVITY AND WERE LESS ELECTRODERMALLY RESPONSIVE THAN WERE THE OTHER GROUPS. THERE WERE NO DIFFERENCES BETWEEN GROUPS IN TONIC HEART RATE OR IN CARDIAC OR DIGITAL VASOMOTOR RESPONSIVITY. HOWEVER, THE PSYCHOPATHS RESPONDED TO SHOCK WITH CEPHALIC VASODILATION WHILE THE NONPSYCHOPATHS RESPONDED WITH VASOCONSTRICTION. IT IS CLEAR FROM THESE RESULTS THAT SIMPLE GENERALIZATIONS ABOUT THE PSYCHOPATH'S CONDITIONABILITY ARE NOT WARRANTED UNLESS THEY ARE RESTRICTED TO ELECTRODERMAL ACTIVITY--PREVIOUS STUDIES SHOW THAT ELECTRODERMAL CONDITIONING IS SUCCESSFUL WITH PSYCHOPATHS. REFERENCES AND TABULAR DATA ARE PROVIDED. (AUTHOR ABSTRACT MODIFIED--DAG)