Divided visual attention and left hemisphere activation among psychopathic and nonpsychopathic offenders

Recent divided attention studies suggest the impulsive antisocial behavior of psychopaths may be related to deficient processing of information under conditions that place substantial demands on left-hemisphere-specific processing resources (left hemisphere activation (LHA) hypothesis; D. S. Kosson [1996, 1998]). To examine performance under conditions constraining eye movements and covert shifts of attention, 26 psychopathic and 46 nonpsychopathic inmates completed a divided attention task in which lateralized stimuli appeared briefly and simultaneously in the left visual field (LVF) and right visual field (RVF) of a monitor. Targets were either presented primarily in the RVF to induce LHA or were equiprobable in LVF and RVF to promote equal activation (EA) of left and right hemisphere resources. Psychopaths were less accurate than nonpsychopaths only under LHA conditions; within-group comparisons also revealed a substantial decrement from EA to LHA only in psychopaths. Thus, psychopaths' performance deficits were specific to conditions priming left hemisphere resources asymmetrically.