RESPONSE MODULATION IN PSYCHOPATHS

Abstract

Psychopathy is characterised by selfishness, callousness, remorseless use of others and social deviance. There has been much speculation that psychopaths do not change or modulate their behaviour in response to external contingencies (response modulation). Empirically, there are mixed findings on whether psychopaths consistently display response modulation deficits, specifically the inability in inhibit dominant responses. A cue-target task that utilised reward and punishment contingencies was used. Participants had to inhibit their responses when either the colour or location of the target was not consistent with the cue. Impulsivity and family history of alcoholism did not affect response modulation. Secondary psychopaths reflected for a longer time following punishment than primary psychopaths. Two behavioural indices emerged to be the best predictors of psychopathy: right hand responses on trials where the left cues preceded right targets (psychopaths had more errors and this was not observed with left responses) and frequency of correct responses on trials following punishment (psychopaths had more errors than nonpsychopaths). These results are interpreted in tenns attentional biases in the two hemispheres. Neurophysiological studies will be necessary to elucidate these mechanisms.