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80 The left hemisphere activation hypothesis of psychopathy
Abstracts
SYMPOSIUM
/International
Journal
14: Psychophysiology of Aggression
80 THE LEFT HEMISPHERE SIS OF PSYCHOPATHY
ACTIVATION
HYPOTHE-
David S. KOSSOII Finch Univ of Health Sciences;/Chicago Medical School, Department of Psychology/The Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064 USA The left hemisphere activation hypothesis proposes that psychopaths are characterized by inefficient cognition under several specific conditions that activate left hemisphere-specific processing resources. In particular, both situations that engender approach motivational states and situations that induce sustained deployment of left hemisphere-specific cognitive resources are proposed to produce relative performance deficits for psychopathic individuals. Several recent studies of psychopaths’ divided attention performance provide evidence consistent with this hypothesis. In particular, studies of incarcerated male inmates identified as psychopathic or nonpsychopathic on the basis of Hare’s Psychopathy Checklist - Revised demonstrate that psychopathic offenders are characterized by relatively general deficits under conditions designed to activate left hemisphere-specific resources. Several of these studies provide independent evidence that experimental manipulations designed to activate hemisphere-specific resources affect the performance of nonpsychopaths as expected on tasks associated with hemisphere-specific advantages. Under conditions that appear to activate left hemisphere resources, psychopaths display deficits in intermodal attention, divided visual attention, nonverbal dichotic listening, facial affect recognition, and selective attention. Thus, these findings suggest a dynamic framework for explaining psychopaths’ adequate cognitive function in many situations that do not place substantial demands on left hemisphere resources, as well as psychopaths’ documented deficits in divided attention, selective attention, language function, and emotional processing. Finally, the hypothesis presents novel implications for our attempts to treat psychopaths’ antisocial behavior.
81 GENDER DIFFERENCES IN BRAIN ACTIVATION DURING AGGRESSIVE IMAGERIES: A PET STUDY P. Pietrinir’~ ‘), M. Guazzelli(3), J. Grafmano) “‘Cognitive Neuroscience Section, NINDS, NIH, Bethesda MD (USA); (2)Department of Human and Environmental Sciences, University of Pisa, Pisa (Italy); ‘3’Department of Psychiatry, University of Pisa, Pisa (Italy) Novel neuroimaging
techniques, including positron emission
of Psychophysiology
30 (1998)
33
7-94
tomography (PET), have made it possible to investigate the brain functional response to sensory and cognitive stimulation and to emotional probing in a non-invasive fashion in humans. The aim of the present study was to examine which cerebral regions are involved in aggressive behavior in healthy subjects and if there are differences between males and females in the pattern of brain response. Eight male (mean age f SD: 22 f 3 yr.; education 16 + 1 yr.) and seven female (22 + 1 yr.; education: 15 + 1 yr.) healthy volunteers were screened to ensure good imagery abilities and exclude history of any medical, neurological or psychiatric disease, substance abuse or behavioral disturbances. Regional cerebral blood flow (rCBF) was measured by using 15-O-water PET while subjects imagined situations involving neutral (control) or distinct aggressive behaviors. Each scan lasted for approximately two minutes; the sequence of presentation of the conditions was randomized and counterbalanced to control for any order effect. Changes in heart rate and blood pressure were measured during each scan through an automatic blood pressure machine. Analogic rating scales were admistered at the end of each scan to measure the capability to imagine the distinct scenes and the degree of emotional response elicited by each condition. Both groups produced detailed and equally clear mental representations for each situation as indicated by the imagery scale scores, and reported significantly greater anger, frustration and anxiety during the aggressive conditions compared to the neutral one. Significant increases in rCBF were seen bilaterally in the cingulate cortex during the aggressive conditions as compared to the neutral scan in the female but not in the male group. In contrast, males but not females, showed significant rCBF increases mainly in the primary and association visual cortical regions. These preliminary results indicate that, despite similar imagery abilities and degrees of emotional response, females imagining aggressive behavior elicited a far more selective response in brain areas crucial for emotional processes whereas the male response was limited to visual cortical areas. These results are consistent with, and further expand on, a previous report (George et al., Biol Psychiatry 40:859, 1996) indicating greater limbic activation in women than in men during transient sadness and may contribute to explain the greater likelihood of females to develop affective disorders as compared to males.
82 EEG CARTOGRAPHY OF ASPERGER’S DROME AND PSYCHOPATHY COMPARED HEALTHY CONTROLS P. Flor-Henry Alberta Hospital, Edmonton, T5J 257, Canada
SYNTO
Box 307, Edmonton, Alberta,
Four subjects with Asperger’s syndrome, two of whom had committed gruesome, senseless and bizarre homicides were compared to each other and to 4 psychopaths who satisfied Hare Psychopathy Check List (score 30 or over) and to 47
SYMPOSIUM
/International
Journal
14: Psychophysiology of Aggression
80 THE LEFT HEMISPHERE SIS OF PSYCHOPATHY
ACTIVATION
HYPOTHE-
David S. KOSSOII Finch Univ of Health Sciences;/Chicago Medical School, Department of Psychology/The Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064 USA The left hemisphere activation hypothesis proposes that psychopaths are characterized by inefficient cognition under several specific conditions that activate left hemisphere-specific processing resources. In particular, both situations that engender approach motivational states and situations that induce sustained deployment of left hemisphere-specific cognitive resources are proposed to produce relative performance deficits for psychopathic individuals. Several recent studies of psychopaths’ divided attention performance provide evidence consistent with this hypothesis. In particular, studies of incarcerated male inmates identified as psychopathic or nonpsychopathic on the basis of Hare’s Psychopathy Checklist - Revised demonstrate that psychopathic offenders are characterized by relatively general deficits under conditions designed to activate left hemisphere-specific resources. Several of these studies provide independent evidence that experimental manipulations designed to activate hemisphere-specific resources affect the performance of nonpsychopaths as expected on tasks associated with hemisphere-specific advantages. Under conditions that appear to activate left hemisphere resources, psychopaths display deficits in intermodal attention, divided visual attention, nonverbal dichotic listening, facial affect recognition, and selective attention. Thus, these findings suggest a dynamic framework for explaining psychopaths’ adequate cognitive function in many situations that do not place substantial demands on left hemisphere resources, as well as psychopaths’ documented deficits in divided attention, selective attention, language function, and emotional processing. Finally, the hypothesis presents novel implications for our attempts to treat psychopaths’ antisocial behavior.
81 GENDER DIFFERENCES IN BRAIN ACTIVATION DURING AGGRESSIVE IMAGERIES: A PET STUDY P. Pietrinir’~ ‘), M. Guazzelli(3), J. Grafmano) “‘Cognitive Neuroscience Section, NINDS, NIH, Bethesda MD (USA); (2)Department of Human and Environmental Sciences, University of Pisa, Pisa (Italy); ‘3’Department of Psychiatry, University of Pisa, Pisa (Italy) Novel neuroimaging
techniques, including positron emission
of Psychophysiology
30 (1998)
33
7-94
tomography (PET), have made it possible to investigate the brain functional response to sensory and cognitive stimulation and to emotional probing in a non-invasive fashion in humans. The aim of the present study was to examine which cerebral regions are involved in aggressive behavior in healthy subjects and if there are differences between males and females in the pattern of brain response. Eight male (mean age f SD: 22 f 3 yr.; education 16 + 1 yr.) and seven female (22 + 1 yr.; education: 15 + 1 yr.) healthy volunteers were screened to ensure good imagery abilities and exclude history of any medical, neurological or psychiatric disease, substance abuse or behavioral disturbances. Regional cerebral blood flow (rCBF) was measured by using 15-O-water PET while subjects imagined situations involving neutral (control) or distinct aggressive behaviors. Each scan lasted for approximately two minutes; the sequence of presentation of the conditions was randomized and counterbalanced to control for any order effect. Changes in heart rate and blood pressure were measured during each scan through an automatic blood pressure machine. Analogic rating scales were admistered at the end of each scan to measure the capability to imagine the distinct scenes and the degree of emotional response elicited by each condition. Both groups produced detailed and equally clear mental representations for each situation as indicated by the imagery scale scores, and reported significantly greater anger, frustration and anxiety during the aggressive conditions compared to the neutral one. Significant increases in rCBF were seen bilaterally in the cingulate cortex during the aggressive conditions as compared to the neutral scan in the female but not in the male group. In contrast, males but not females, showed significant rCBF increases mainly in the primary and association visual cortical regions. These preliminary results indicate that, despite similar imagery abilities and degrees of emotional response, females imagining aggressive behavior elicited a far more selective response in brain areas crucial for emotional processes whereas the male response was limited to visual cortical areas. These results are consistent with, and further expand on, a previous report (George et al., Biol Psychiatry 40:859, 1996) indicating greater limbic activation in women than in men during transient sadness and may contribute to explain the greater likelihood of females to develop affective disorders as compared to males.
82 EEG CARTOGRAPHY OF ASPERGER’S DROME AND PSYCHOPATHY COMPARED HEALTHY CONTROLS P. Flor-Henry Alberta Hospital, Edmonton, T5J 257, Canada
SYNTO
Box 307, Edmonton, Alberta,
Four subjects with Asperger’s syndrome, two of whom had committed gruesome, senseless and bizarre homicides were compared to each other and to 4 psychopaths who satisfied Hare Psychopathy Check List (score 30 or over) and to 47