Behavioral evidence of prolonged interhemispheric transfer time among psychopathic offenders.

Abstract

Several lines of evidence suggest the possibility of abnormal interhemispheric communication in psychopathy, but there have been few direct empirical studies. To address this gap in the literature, we examined one important aspect of interhemispheric communication, the efficiency with which information is transferred across the corpus callosum. Using Poffenberger's (1912) paradigm for estimating interhemispheric transfer time (IHTT) from simple motor responses to lateralized stimuli, we found a substantially prolonged IHTT among psychopathic criminals relative to nonpsychopathic criminals. This prolonged IHTT was somewhat more pronounced when participants were using their right hand to respond. This study provides initial behavioral evidence of slowed interhemispheric transfer in psychopathy.

Psychopathy and instrumental aggression: Evolutionary, neurobiological, and legal perspectives

“…They suggest that impaired connectivity between hemispheres may cause functions primarily mediated by the left hemisphere (e.g. approach behavior and language processing) to be relatively unmodulated by functions mediated predominantly by the right hemisphere (e.g., behavioral inhibition and emotion processing) and vice versa (Hiatt & Newman, 2007).…”

“…The corpus callosum is the major connection between the two hemispheres. Recently, Hiatt and Newman (2007) found that the time required to transfer information from one hemisphere to the other is significantly prolonged in criminal psychopaths compared to criminal non-psychopaths. This effect was more pronounced in right-handed response conditions, which are controlled by the left hemisphere.…”

The Early Attachment Experiences are the Roots of Psychopathy

“…According to them even the less lateralized emotion processing also reflects poor hemispheric integration and a greater distribution of functions that are usually lateralized in the right hemisphere. Hiatt & Newman (2007) documented that trials in which the psychopaths used their right hands showed evidence of slowed interhemispheric transfer. A finding which is not consistent with the LHA as the psychopaths' deficits were specific to interhemispheric transfer rather than their overall performance.…”

Abnormal interhemispheric connectivity in male psychopathic offenders

“…In addition, the results also suggest that signal transfer from the right to the left frontal cortex connectivity may be specifically affected in psychopathic offenders. 10 However, direct neurophysiological evidence providing substantiation of right to left interhemispheric connectivity abnormalities in psychopathic offenders is lacking.…”

“…Indirect evidence from functional magnetic resonance imaging (fMRI) in the same study suggests that functional interhemispheric connectivity is increased in psychopathic offenders. 9 Using behavioural measurements, Hiatt and Newman 10 suggest a possible directional component to these connectivity abnormalities, as psychopathic offenders have a prolonged interhemispheric transfer time. In addition, the results also suggest that signal transfer from the right to the left frontal cortex connectivity may be specifically affected in psychopathic offenders.…”