Emotion and attention in the psychopath : an investigation of affective response and facilitated attention using event related potentials.

Abstract

A prominent concern in psychopathy research is a deficit in processing emotionally relevant information, which may occur in the very early neural processing stages of stimulus evaluation. While contemporary functional imaging techniques like fMRI have unparalleled spatial resolution, their poor temporal resolution makes them inadequate for measuring the time-course of very early stages of information processing. Conversely, electrocortical measures, particularly event related potentials (ERPs), are capable of determining the time-course of such processing on the order of milliseconds. The goal of this investigation was to establish the existence of differences between psychopaths and controls in their integration of emotional information in the very early stages of information processing as indexed by ERP waveform differences, and determine whether manipulations of attentional focus are capable of modulating these differences. In a series of presentations of emotionally evocative pictures and words, psychopaths and controls indeed displayed robust differences in their ERP waveforms. Psychopaths lacked a persistent emotion-related positivity present in controls beginning around 200 ms into the processing stream and continuing throughout the 900 ms epoch of interest. Under conditions where the emotional information was relevant to an ongoing task, psychopaths showed moderate changes in ERPs for emotional stimuli, yet these waveforms remained dissimilar from those of controls. These data provide evidence that psychopaths present with deficits in early-stage discrimination of emotionally salient information, which may be partially sensitive to manipulations of effortful attention. These outcomes have implications for later-stages of processing such as the integration of this information into memory systems and the utilization of this information for the modification of ongoing behavior.