Handbook of Psychopathy Chapter 14 Notes: Neuroanatomical Bases of Psychopathy

Chapter 14 Neuroanatomical Bases of Psychopathy

Regarding function, during an aversive conditioning paradigm (distinct
concept), psychopaths w/APD show atypically increased activation in
the amygdala (Schneider et al., 2000). In contrast, Kiehl et al.,
2001, using fMRI found reduced activation in the amygdala-hippocampal
complex in criminal psychopaths when processing affective stimuli. Muller et
al., 2003, observed reduced activation in the left parahippocampal
gyrus in psychopaths in response to negative affect stimuli. Soderstrom et
al., 2000, failed to observe significant correlations between both
amygdala and hippocampal frontal blood flow in relation to total
psychopathy scores (Soderstrom et al., 2002).
p. 281.

angular gyrus (parietal lobe) deficits = cognitive dysfunctions =
violent offenders
Reductions in glucose metabolism in the left angular gyrus in parietal
lobe (http://en.wikipedia.org/wiki/Angular_gyrus) in violent offenders
(Raine et al., 1977) have been correlated with reduced verbal ability
(Gur et al., 1994), while damage to the left angular gyrus has been
linked to deficits in reading and arithmetic. Such cognitive
dysfunctions could predispose to educational and occupational failure,
which in turn might predispose to crime and violence. Such learning
deficits have been found to be common in violent offenders who also
have low verbal IQs (Raine, 1993).
p. 288.

angular gyrus activation in murders v Factor 1 psychopathy scores
Two studies have assessed functioning in the angular gyrus within the
parietal lobe though none has studied psychopaths in particular . Raine et al.,
1997, found reduced glucose metabolism in the left – not right –
angular gyrus in murders. In a SPECT study, Soderstrom et al., 2000,
found violent offenders showed reduced functioning in the angular
gyrus; the deficit was to the right – not left – angular gyrus. There
are correlations between reduced left angular gyrus functioning and
increased Factor 1 psychopathy scores.
p. 282.

baby prefrontal cortex injuries
cause-effect relationship. Anderson, Damasio, Tranel & Damasio (2001)
reported 2-individuals who suffered selective lesions to the
prefrontal cortex in the first-16-months of life: female: bilateral
polar and ventromedial; male: right polar-medial-dorsal
Both showed early antisocial behavior that progressed into delinquency in
adolescence and criminal behavior in adulthood and included
impulsive-aggressive and nonaggressive forms of AB. Both had
autonomic deficits, poor decision making skills, and deficits on
learning from feedback.
p. 286.

Brain deficits in psychopaths causes
Environmental factors may play a role in shaping structural brain
deficits in psychopaths. Head injuries from child abuse, accidents,
fights and sports are an important source of brain damage. Closed
head injuries are particularly likely to create damage to the frontal
and temporal poles, and thus it is not surprising that anterior
(frontal and temporal) abnormalities are particularly implicated in
psychopathic and antisocial behavior.
p. 288.

Brain deficits in psychopaths causes: birth oxygen shortage =
hippocampus cell death
Early Health factors could be a source of brain impairment. Birth
complications have been associated with violence (Raine, 2002b), and a
lack of oxygen at birth leads to cell death, particularly in the
hippocampus [located in the medial temporal lobe]
(http://en.wikipedia.org/wiki/Hippocampus), a brain region linked to
violence in psychopathy (Laakso et al., 2001; Raine et al., 2004).
p. 289.

Brain deficits in psychopaths causes: corpus callosum trauma
Raine et al., 1997) revealed a trend in a study of murderers
with a history of head injury to have lower functioning of the corpus
callosum than murderers w/out head injury; it is known that long white
nerve fivers are susceptible to sheering during closed head injuries.
Other brain deficits found included reduced prefrontal glucose
metabolism, were not linked to a history of head injury.
p. 288-289.

Brain deficits in psychopaths causes: early environmental health
factors & genetics
In all likelihood, brain deficits in psychopaths are likely caused by
a combination of early environmental health factors and genetic
processes. Twin and adoption studies have demonstrated beyond doubt
that there is heritability for criminal behavior (Raine, 2002a); it is
likely that psychopathic behavior has a significant heritable
component (cf. Waldman & Rhee, Ch. 11: Genetic & Environmental
Influences on Psychopathy). In an MRI study (Thompson et al., 2001),
90-95% of the variance in prefrontal volume is determined by genetic
factors. Consequently, genetic factors are likely to play some role
in producing the type of structural prefrontal gray deficits found in
those w/psychopathic behavior & APD.
p. 289.

Brain deficits in psychopaths causes: fetal alcohol syndrome & smoking
during pregnancy
Fetal alcohol syndrome in which the fetus is exposed to alcohol in
utero results in significant structural and functional brain deficits
and could contribute to brain deficits in psychopaths. Smoking during
pregnancy is linked to outcome for adult violence (Brennan, Mednick &
Hodgins, 2000) and can lead to brain impairments by reducing oxygen to
the fetal brain (Raine, 2002b).
p. 289.

Brain deficits in psychopaths causes: murderers w/child abuse relative
to w/out child abuse
Raine, Park et al., 2001, did an fMRI study that found that violent
offenders with a history of child abuse had greater brain dysfunction
than nonabused violent offenders, suggesting the potential importance
of environmental factors in the etiology of functional brain
impairments. Conclusion: murderers w/serious child abuse early in
childhood were not found to suffer from brain deficits relative to
murderers w/out such abuse (Raine, Stoddard, et al., 1998).
p. 289.

Brain deficits in psychopaths causes: protein deficiency = corpus
callosum & forebrain impairments
Protein deficiency leads to poor brain development which has been
linked to AB problems (Liu, Raine, Venablis & Mednick, 2004);
Neugebauer, Hock & Susser, 1999). Rats fed a low-protein diet during
pregnancy show impairments in corpus callosum functioning (Soto-Moyano
et al., 1998) and reduction in DNA concentration in the forebrain
(Bennis-Taleb, Remacle, Hoet & Reusens, 1999), two brain areas found
to be impaired in psychopaths.
p. 289.

Brain deficits in psychopaths causes: structural & functional brain
deficits not from substance abuse
Drug & alcohol abuse in theory could contribute to brain deficits in
psychopaths. But these factors may not be as salient as they first
appear. For example, APD individuals w/high psychopathy scores show
significant prefrontal gray reductions not only compared to normal
controls but also compared w/group w/alcohol- and drug-dependence
individuals not diagnosed w/APD – indicating that substance abuse does
not account for the structural brain deficits (Raine et al., 2000).
Critchley et al., 2000; Hirono et al., 2000, Kuruoghu et al., 1996;
showed that when drug/alcohol abuse is controlled for, structural &
functional brain deficits in violent offenders argues against this
conclusion.
p. 289.

corpus callosum dysfunction & concurrent limbic and cortical
abnormalities
Both Sperry (1974) & Diamond commented on the inappropriate nature of
emotional expression and the inability to grasp long-term implications
of a situation in split-brain patients. Parallel influences may
contribute to inappropriate and emotional egression of violent
psychopaths and their lack of long term planning. But, corpus
callosum dysfunction per se is unlikely to cause aggression and
psychopathy; instead it may contribute to psychopathy in those with
concurrent limbic system& cortical abnormalities.
p. 287.

child head injuries = behavior problems
cause-effect relationship. Studies of the behavioral sequelae that
follow head injuries in children. Overwhelmingly, studies on
childhood head injuries reveal that conduct disorder (CD) and
externalizing behavior problems are common after head trauma (Raine,
2002a), although some children develop internalizing v externalizing
behavior problems v other remain relatively unaffected.
p. 286.

child head injuries = CD or labile/uncontrollable behavior
cause-effect relationship. Pennington & Bennetto (1993) reported on
9-cases of children suffering frontal brain lesions in the first
10-years of life. All 9 suffered behavioral problems; 7-of-9 having
CD or conduct disorder, 2 exhibiting labile or uncontrollable
behavior.
p. 286.

corpus callosum deficits disrupt left-hemisphere inhibitory processes
Deficits to the corpus callosum and the consequent abnormal
interhemispheric transfer may result in the right hemisphere, which
has been implicated in the generation of negative affect (Davidson &
Fox, 1989), undergoing less regulation and control by left-hemisphere
inhibitory processes. This impairment in affect regulation may in
turn contribute to the expression of aggressive and unregulated
behavior. Rats that are stressed early un life are right-hemisphere
dominant for mice killing (Garbanati et al., 1983). Severing the
corpus callosum in these rats leads to an increase in muricide
((biology) A mouse-killing instinct in rats.) (Denenberg, Gall,
Berrebi & Yutzey, 1986), indicating that the left hemisphere acts to
inhibit the right-hemisphere mediated killing via an intact corpus
callosum.
See: BAS & BIS.
p. 287.

corpus callosum neurodevelopmental failure = social insight &
self-perception deficits
Individual who suffer from neurodevelopmental mental failure of the
corpus callosum, while not showing gross psychopathology, do show
deficits in social insight and self-perception (Brown & Paul, 2000),
deficits which also characterize psychopaths. As such, abnormal
interhemispheric connectivity may partly account for the social,
insight, autonomic, and emotion deficits observed in psychopaths.
p. 288.

corpus callosum structural abnormalities
Raine et al., 1997, using PET found that murderers exhibited decreased
metabolic activity in the corpus callosum compared to normal controls. Raine, Lencz & colleagues (2003) found that compared to controls, psychopathic-AB individuals showed
pronounced corpus callosum structural abnormalities. Larger callosal
volumes were associated w/affective & interpersonal deficits, low
autonomic stress reactivity, and low spatial ability.
p. 282.

Corpus Callosum white matter volume = Deficient Affect factor of
psychopathy
Key feature of psychopathy is blunted affect, and low autonomic
activity during emotional and social stressors is a well-replicated
correlate of psychopathy (Hare, 1982; Patrick, Zempolich & Levenston,
1997). Callosal white matter volume was significantly related to the
Deficient Affect factor of psychopathy, and to a lesser extent the
Impulsive-Irresponsible factor, but not the Arrogant/Deceptive factor.
Similarly, autonomic measures & personality measures reflecting
blunted affect, lack of social closeness, and no close friends were
related to callosal abnormalities.
p. 287-288.

frontal & prefrontal dysfunction in affective, impulsive murderers
There may be different brain bases to impulsive, affective violence v
predatory, planned violence (Davidson et al., 2000; ; Scarpa & Raine,
2000). Frontal abnormalities may be more pronounced in individuals
engaging in impulsive v premeditated aggression. Raine, Meloy et al.,
1998, found prefrontal dysfunction to be specific to affective,
impulsive murders v predatory, instrumental murderers.
p. 282.

frontal activation in psychopaths during negative affect challenge
Psychopaths have shown increased activation to negative affect picures
in the right medial prefrontal cortex along with increased left orbitofronal
activation (Muller et al., 2003). In a resting state using SPECT, no
significant correlations were observed between frontal blood flow and
total psychopathy scores in violent offenders (Soderstrom et al.,
2002). Taken together, studies using negative affect emotional
challenge indicate if anything increased, NOT decreased, frontal
activation in psychopaths (Schneifer et al., 2000). It is possible
that psychopaths may paradoxically show enhanced activity because they
have fear conditioning and emotional deficits; thus, to perform the
behavioral activation task as well as controls, greater
neurophysiological activation is required.
p. 280.

frontotemporal
A SPECT study (Intrator et al., 1977) found that psychopaths show
increased bilateral blood flow in frontotemporal regions during the
processing of emotional words. But, studies suggest that this effect
may be specific to the frontal contribution to the effect. In a
resting state, a SPECT study found no correlations between bilateral
blood flows in a group of violent psychopathic offenders (Soderstrom
et al., 2002). But, activation was reduced (not increased) in the
right temporal gyrus (A longitudinal gyrus on the lateral surface of the temporal lobe of
the brain, between the superior and inferior temporal sulci; middle
temporal gyrus.) in psychopaths in response to negative stimuli
(Muller et al., 2003). So, unlike broad-based antisocial personality
(AB, ASPD), psychopathy may not be associates with temporal lobe
functioning.
p. 281

frontotemporal dementia (FTD) = AB behavior
cause-effect relationship. A SPECT study (Mychack, Kramer, Boone &
Milller,2001) of patients w/right-sided – not left-sided –
frontotemporal dementia revealed evidence of socially undesirable
behavior, including criminality, aggression, and sexually deviant
behavior among these patients.
p. 286.

frontotemporal dementia (FTD) = aggressive dementia patients
cause-effect relationship. Raine (2002b) diagnosed patients
w/degenerating brain diseases like frontotemporal dementia (FTD) are
significantly more likely to engage in inappropriate aggressive,
sexual, and AB than patients with Alzheimer’s disease (Miller,Darby,
Benson & Cummings, 1997. Aggressive dementia patients (i.e.,
Alzheimer’s disease & vascular dementia) show significant
hypoperfusion (i.e., left activation) in the left and right
dorsolateral frontal areas, left anterior temporal cortex
and right superior parietal areas compared to
nonaggressive dementia patients (Hirono et al., 2000). p. 286.
hippocampus asymmetry in psychopaths
Regarding structure, Laakso et al., 2001, in an MRI study, found
reductions in the volume of the posterior hippocampus to be associated
with increased psychopathy scores in AB alcoholics. More complex
structural abnormalities are reported by Raine et al., 2004,
implicating abnormal asymmetry in the anterior hippocampus. Tiihonen,
Hodgins & Vaurio, 2000, reported reduced amygdala volume to be
associated with increased psychopathy scores.
pp. 281-282.

Increased activation: rCBF of frontotemporal regions, dorsolateral: =
less activation in subcortical regions
Drug-abusing psychopaths compared to drug-abusing nonpsychopaths and
controls show increased rCBF [Relative Cerebral Blood Flow (magnetic
resonance)] bilaterally in frontotemporal
(http://en.wikipedia.org/wiki/Frontotemporal_dementia) regions during
the processing of negative affect words. During and aversive
condition paradigm (One that serves as a pattern or model),
psychopaths with APD show atypically increased activation in the
dorsolateral prefrontal cortex
(http://www.psych-it.com.au/Psychlopedia/article.asp?id=191). In an
affective memory task, psychopaths show overactivation of
frontotemporal regions, and in this study showed decreased activation
in subcortical regions. Kiehl et al., 2001.
p. 280.

AB abnormal brain areas
To date, the key brain areas that have been shown to be abnormal in AB
individuals: prefrontal cortex, temporal cortex, amygdala-hippocampal
complex (http://pbmo.wordpress.com/2011/05/21/amygdala/), the corpus
callosum and angular gyrus
p. 278

lying & brain activation areas in normal individuals
Spence et al., 2001, using a computer based interrogation procedure
fund that lying was associated w/both a longer response time and
greater activation in bilateral ventrolateral prefrontal cortices
Lee et al., 2002, found normals who feign memory impairments when
tested using a forced-choice format showed greater activation in a
prefrontal-parietal-subcortical circuit. A study of 2-types of lying – well-rehearsed v spontaneous lies – found that both types elicited more bilateral activation in the anterior prefrontal cortex bilateral parahippocampal gyrus, the right precuneus and left
cerebellum/ (Ganis, Kosslyn, Stose, Thompson & Yurgelun-Todd, 2003). Common to these studies is increased activation in the prefrontal cortex during lying.
p. 283.

murderers from benign backgrounds = right orbitofrontal cortex low
functioning
In a PET study, Raine, Stoddard, Bihrle & Buchsbaum (1988), used PET:
frontal deficits were found to be particularly pronounced in violent
individuals who had not been exposed to significant social stressors.
Murderers from nondeprived home backgrounds (benign background, high
SES) showed a 14.2% reduction in functioning of the right
orbitofrontal cortex relative to murderers from deprived home backgrounds characterized by abuse, neglect, and marital violence. It is argued that neurobiological deficits are more pounced in violent individuals who lack the psychosocial deprivation that normally provides a “social push” toward violence. The dependent variable is brain functioning.
p. 284-285.

neurodevelopment abnormal: anterior hippocampus asymmetry from fetal
development
Asymmetry in the structure of the anterior hippocampus in
psychopaths may have a neurodevelopmental explanation (Raine et al.,
2004). Atypical brain asymmetries are thought to in part reflect
disrupted neurodevelopmental processes. The disruptions occur early
in life as brain asymmetries first emerge during fetal development and
the overall degree of structural change attributable to environmental
influences is limited by early morphogenesis. A neurodevelopmental
perspective of psychopathy is consistent w/the facts that has its
roots early in life, unfolds relatively consistently over childhood
and adolescence, is impervious to conventional treatments, and is in
part genetically determined (Raine et al., 2004).
p. 288.

neurodevelopment abnormal: corpus callosum asymmetry in psychopaths
Regardless of the ways in which impairments to specific brain regions
can give rise to cognitive and behavioral alterations that predispose
to psychopathy, one single process may underlie these multiple
processes. Specifically, structural and functional brain impairments
in psychopaths may be caused by abnormal neurodevelopment (Raine et
al., 1005, 2004; Raine, Lencz, et al., 2003). Research on monkeys,
cats and hamsters shows about 2/3rds of callosal axons are eliminated
postnatally through adulthood, w/most of pruning being to excitatory
rather than inhibitory fibers (Raine, Lencz et al., 2003). Early
arrest of the pruning could contribute to the increased callosal white
matter volume and functional over-connectedness of the hemispheres
bereaved in psychopaths (Raine, Lencz et al., 2003).
p. 288.

neurodevelopment abnormal: life-long persistent AB/psychopathy
Regarding frontal impairments, it has been hypothesized (Raine et al.,
2000b) that the social and executive function demands of late
adolescence place an overload on the late-developing prefrotal cortex,
giving rise to a lack of inhibitory control over antisocial,
aggressive behavior which reaches maximal expression at this age.
This prefrontal overload is hypothesized to be particularly likely in
individuals with developmental delays in prefrontal maturation or in
hyperactive children w/preexisting prefrontal deficits. Furthermore,
persistence into adulthood of antisocial and psychopathic behavior is
thought to be especially likely in those who have suffered head trauma
that may prevent a maturational catchup of the prefrontal cortex in
adulthood.
p. 288.

prefrontal damage = AB/psychopathic traits
Patients w/prefrontal damage fail to give anticipatory autonomic
responses to choice options that are risky and make bad choices even
when they are aware of the more advantageous response option (Bechara,
Damasio, Tranel & Damasio, 1997). This inability to reason and to
make appropriate decisions in risky situations is likely to contribute
to the impulsivity; rule breaking; poor behavioral control; lack of
realistic, long-term goals; and irresponsible behavior that
characterize psychopaths (Hare, 1991).
pp. 286-287.

prefrontal damage = arousal regulation abnormalities
Prefrontal dysfunction may result in abnormalities in arousal
regulation which in turn predispose to psychopathy. The prefrontal
cortex is involved in the regulation of arousal (Dahl, 1997). Low
physiological arousal has been associated w/stimulation-seeking
behavior to compensate for such underarousal (Eysenck, 1977;
Zuckerman, 1994), behavior which characterizes both psychopathic and
AB populations (Gatzke, Raine, Loeber, Steinhauer &
Strouthamer-Loeber, 2002; Raine, 1993).
p. 287.

prefrontal damage = electrodermal arousal & prefrontal gray integrity
Those w/lowest skin conductance had the lowest prefrontal gray
volumes, indicating a link between electrodermal arousal and
prefrontal gray integrity. This arousal and stress reactivity
dysregulation produced by damage to the prefrontal cortex may
contribute to emotional regulation problems that in turn contribute to
emotion regulation problems that in turn contribute to aggressive and
psychopathic behavior (Davidson et al., 2000; Scarpa & Raine, 2000).
p. 287.

prefrontal damage = poor fear conditioning
Prefrontal abnormalities may result in poor fear conditioning which
has been consistently found in psychopathic and AB groups (Hare &
Quinn, 1971; Lykken, 1957; Raine, 1993; Patrick, 1994). The
prefrontal cortex is part of a neural circuit that plays a central
role in fear conditioning and stress responsivity (Frysztak & Neafsey,
2002; Hugdahl, 1998).
p. 287.

prefrontal damage = psychopathy predisposition
Poor conditioning is theorized to be associated w/poor conscience
development (Eysenck, 1977; Raine, 1993), and individuals who are less
autonomically responsive to averse stimuli such as parental verbal and
physical punishment during childhood would be less susceptible to
socializing punishments and hence become predisposed to psychopathy.
p. 287.

prefrontal damage = reduced prefrontal gray matter
Raine et al., (2003) reported that individuals w/APD have reduced
prefrontal gray volume and also showed lower autonomic activity (both
skin conductance and hear rate) during a social stressor task in which
subjects had to prepare and give a speech about their worst faults – a
task well suited to eliciting secondary emotions such as shame, guild
and embarrassment, which are though to be mediatged by the
ventromedial prefrontal cortex (Damasio, 1994).
p. 287.

prefrontal gray volume low, psychosocial deficits, autonomic
responsivity low = violence
Do brain deficits combine w/psychosocial deficits in predisposing to
violence? When the outcome variable is psychopathy/violence, it
appears that brain deficits can combine w/family deficits in the
prediction of AB. An aMRI study (anatomic MRI for volumetric
measurement) of APD individuals & high psychopathy scores (Raine et
al., 2000) showed that the combination of reduced prefrontal gray
volume, low autonomic responsivity, and a set of 10 psychosocial
deficits (e.g., abuse, single family, & parental criminality)
correctly classified 88.5% of subjects into APD or control groups
(compared to 73.0% for psychosocial predictors only and 76.9% for
biological predictors only).
p. 284-285

prefrontal gray volume reduced = psychopathy
Yang et al., 2005, using an MRI in a community sample w/wide range of
psychopathy scores, found significant negative correlations between
prefrontal gray volume and total PCL-R scores, Factor 1 scores, and
Factor 2 scores, indicating reduced prefrontal gray volume in those
w/high psychopathy scores. Similar correlations were observed between
prefrontal gray volume and 3-factors of psychopathy defined by Cooke
& Michie (2001) as Arrogant and Deceitful Interpersonal Style,
Deficient Affective Experience,and Impulsive & Irresponsible
Behavioral Style. The size of the correlations was similar across the
psychopathy factors, indicating that reduced prefrontal gray was a
common denominator to all features of psychopathy.
p. 283-284.

prefrontal inhibitory control of subcortical activity: premeditated v
impulsive murderers
Common to impulsive and premeditated murderers is increased
subcortical activity (midbrain,amygdala, hippocampus, and thalamus)
compared to controls. While premeditated murderers may have
sufficient prefrontal regulation to control the excess aggressive
feelings generated subcortically, this inhibitory control may be
lacking in the affective, impulsive murderers. Frequency of impulsive
aggression is associated with reduced glucose metabolism in the
frontal cortex of patients w/personality disorders (Goyer et al.,
1994). Impulsive violent offenders also exhibit reduced
frontotemporal cerebral blood flow (Soderstrom et al., 2000).
p. 282.

prefrontal ventral damage = executive function & autonomic deficits, &
sociopathic behavior
Damage to the brain can indeed directly contribute to the etiology of
psychopathic and antisocial behavior. Individual once normal who
suffered brain lesions allows cause-effect relationships to be teased
out. Damasio & colleagues (Damasio, 1994; Damasio, Tranel & Damasio,
1990) have convincingly demonstrated that damage to the ventral
regions of the prefrontal cortex results in poor decision making, autonomic deficits and sociopathic behavior.
p. 285-286.

prefrontal white high v gray in psychopathic & APD liars
Prefrontal gray and white matter volumes were assessed w/MRI in 12
liars, 16 AB subjects, and 21 normal controls, Yang et al., in press).
liar definition: 1) psychopathic lying on PCL-R; 2)
conning/manipulative on PCL-R; 3) DSM-IV APD criterion; 4) admitted to
malingering (lying to get sickness benefits). Liars showed a 22-26%
increase in prefrontal white matter, a 36-42% reduction in prefrontal
gray/white rations compared to both AB and normal controls. The
findings provide evidence of a structural brain deficit in liars and
indicate that excessive prefrontal white matter relative to gray may
act as a predisposition to specific features of psychopathy. p. 283.

psychopaths v impulsives show normal/increased brain activation
Contrasting with impulsive affective violent offenders, psychopaths
appear to show normal or increased (not decreased) patterns of brain
activation v nonpsychopathic offenders and controls. Noted earlier,
psychopaths show increased bilateral blood flow in frontotemporal
regions during the processing of emotional words (Intrator et al.,
1997), increased activation in both the dorsolateral prefrontal cortex
and amygdala during an aversive conditioning paradigm (Schneider et
al., 2000), and over activation of frontotemporal regions (Kiehl et
al., 2001).
p. 283.

Psychopathy & Brain Functioning
A study deserving attention correlates the 2-factor & 3-factor
psychopathy structure to resting blood flow throughout the brain and
observed effects for subfactors that were not observed for total
psychopathy scores.
p. 284.

psychosocial risk factors w/ corpus callosum measure =
psychopathic/antisocial behavior
A structural (volumetric) brain imaging study of the corpus callosum
in psychopaths showed that the combination of psychosocial risk
factors w/callosum measures accounted for 81.5% of the variance. But
in both studies, it should be noted that structural brain measures
accounted for the significant increase in the variance of
psychopathic/antisocial behavior over and above psychosocial risk
factors (Raine et al., 2000).
p. 285.

reduced blood flow & glucose metabolism from PET & SPECT scans
Reviews of brain imaging studies of violent and AB populations
conclude that the brain region most likely to be compromised is the
prefrontal cortex. PET (Positron emission tomography) scans in an
auditory activation condition, showed that an increased number of
impulsive-aggressive acts was associated with reduced glucose in the
frontal cortex in patients w/personality disorders. Another PET in a
nonactivation, eyes open, resting state observed reduced glucose
metabolism in both prefrontal and medial temporal regions. Using
SPECT(Single Photon Emission Computed Tomography), found reduced blood
flow in both the frontal and temporal lobes in individuals convicted
of impulsive violent offenders.
p. 279-280.

reduced hippocampal functioning in violent offenders
Functional impairments of the hippocampus and amygdala
have been observed in violent offenders. Abnormal asymmetries of functioning were found in a PET study of murderers, w/murderers showing lower left and increased right
functioning in both the amygdala and hippocampus compared to controls
(Raine et al., 1997). Soderstrom et al. 2000, in a SPECT study found
bilaterally reduced hippocampal functioning in violent offenders.
p. 281

reduced prefrontal gray matter
The first aMRI (anatomic MRI) [volumetric measurements] of APD w/high
scores on the PCL-R showed an 11% reduction in the volume of gray
matter in the prefrontal cortex compared w/normal controls and a
substance dependance control group (Raine et al., 2000). The deficit
was specific to prefrontal gray matter as opposed to white. Laakso et
al., 2002, found reduced MRI left prefrontal gray volumes
(dorsolateral, orbitofrontal and medial prefrontal) in alcoholics w/AB
personalities compared to controls.
p. 280.

supportive environment buffers prefrontal cortex damage
Neurological case studies hint at a possible role of a structured,
benign home background in buffering against an antisocial outcome
after prefrontal damage. Phineas Gage did not engage in significant
criminal or violent activities; he was taken in by his family. In
Spain, a man like Phineas, had a spike destroy his prefrontal cortex,
was taken in by his family and employed and married and had 2-healthy
children; the family protected him the rest of his life. Patient MSG
(Dimitrov, Phipps, Zahn & Grafman, 2002) suffered from the frontal
lesions in early adulthood but was rehabilitated and cared for in a
structured, supportive environment and did not exhibit criminal,
violent behavior.
p. 285.

temporal lobe abnormalities
Poor cortical temporal functioning is related to AB. Reduced glucose
metabolism has been found in medial temporal regions of violent patients (Volkow et al., 1995). The number of localized temporal lobe changes identified through
electroencephalograph (EEG) and CT (computerized tomography) have been
associated positively w/severity ratings for preadmission violence
among offenders w/mental disorders (Wong, Lumsden, Fenton & Fenwick,
1994). In two brain imaging studies, temporal lobe abnormalities are
more prevalent in aggressive v nonaggressive psychiatric patients
(Amen, Stubblefield, Carmichael & Thisted, 1996; Wong, Lumsden, Fenton
& Fenwick, 1997). Aggressive dementia patients have also been found
to show reduced blood flow in the left anterior temporal lobe
(http://interaxon.ca/blog/wp-content/uploads/2011/02/anteriortemporallobe.jpg)
as measured by SPECT (Hirono, Mega, Dinov, Mishkin & Cummings, 2000).
p. 280-281.

temporal lobe dysysfunction = frontotemporal dysfunction
Many temporal lobe (http://en.wikipedia.org/wiki/Temporal_lobe)
functional abnormalities in aggressive populations may reflect
frontotemporal dysfunction as evidenced by the fact that studies found coexisting frontal deficits. Different imaging technologies may be sensitive to dysfunction in different
regions: EEG found abnormalities in the temporal lobes of murderers;
PET scans did not reveal evidence for temporal lobe dysfunction. In
terms of structure, Donlan et al., 2002, found 20% in temporal lobe
volume in impulsive-aggressive patients with personality disorders.
p. 281.

two- & three factor psychopathy structure correlated in SPECT study I
Soderstrom et al., 2002, in a SPECT study of 32 violent offenders,
correlated both the 2- & 3-factor psychopathy structure to resting
blood flow throughout the brain & observed subfactors not observed for
total psychopathy scores. Significant correlations were observed
between high scores on Hare’s Factor 1 (affective/interpersonal) &
reduced left basal prefrontal, left overall prefrontal, and
bilateral temporal blood flow.
P. 284.

two- & three factor psychopathy structure correlated in SPECT study II
This pattern of result was replicated for Cooke’s Factor 1
(arrogant/deceptive) w/addition of reduced blood flow in the right –
not left – basal prefrontal cortex, reduced left – not right – angular
gyrus, the right head of the caudate, and the left. High scores on Cooke’s Factor 2 (affective) were associated w/reduced left hippocampal and caudate functioning. No other effects were observed for Hare’s Factor 2 (antisocial life style) or Cooke’s Factor 2
(affective) and Factor 3 (impulsive/unstable).
P. 284.

unsuccessful psychopaths & hippocampus volumes
Raine et al., 2004, assessed left & right hippocampus volumes w/aMRI
(anatomic MRI, volumetric measurements) in 23 controls, 16
unsuccessful (caught) psychopaths, & 12 successful (uncaught)
community psychopaths. Unsuccessful psychopaths showed exaggerated
structural hippocampal asymmetry (right > left) relative to both
successful psychopaths & controls, findings which were localized to
the anterior region. This effect could not be explained by environmental or diagnostic
confounds. Atypical anterior hippocampal asymmetries in unsuccessful
psychopathy may reflect underlying neurodevelopmental abnormality that
disrupts hippocampal-prefrontal circuitry, resulting in affect dysregulation, poor contextual fear conditioning, and insensitivity to cues predicting capture.
p. 284.

Yang, Raine, Lencz, LaCasse and Colletti, 2005, using an aMRI
(anatomic MRI, volumetric measurements) on 23 controls, 16
unsuccessful (caught) psychopaths, & 12 successful (uncaught)
community psychopaths, revealed a significant 18-23% reduction in
prefrontal gray matter only in unsuccessful psychopaths compared to
both successful psychopaths and controls. These findings understood
in the context of the Somatic Marker Hypothesis of Damasio, 1994,
which argues that intact prefrontal functioning plays a role in good
decision making, autonomic anticipatory fear, and social regulation.
p. 284.

unsuccessful psychopaths have prefrontal gray reduced
Ishikawa, Raine, Lencz, Bihrle & LaCasse (2001) have shown reduced
autonomic stress reactivity and executive function deficits in this
same group of unsuccessful psychopaths. Poor decision making, reduced
autonomic reactivity to cues predictive of punishment, and reduced
prefrontal gray may render unsuccessful psychopaths less sensitive to
environmental cues signaling danger and capture and hence make them
more prone to conviction. Previous correlations between high
psychopathy scores and reduced prefrontal gray volume may be specific
to unsuccessful not successful psychopaths.
p. 284.

ventromedial v orbitofrontal lesions
cause-effect relationship. A quasi-experimental group study on head
injuries in soldiers revealed that individuals with ventromedial
(http://www.nimh.nih.gov/images/pubs/ptsd-brain.gif) lesions showed
greater aggressive, violent, and/or antisocial behavior than
individuals with nonfrontal lesions,or nonlesion controls (Grafman et
al., 1996). Of these ventromedial patients, those w/local frontal
medial lesions were generally aware of and able to self-report the
increase in their aggressive behavior v those with focal orbitofrontal
lesions were aware of the behavioral change.
p. 286.

violent offenders = amygdala-hippocampal volume reductions
In a study of repetitively violent patients, Critchley et al., 2000,
showed reduced NAA (N-acetyl aspartate) in the amygdala-hippocampal
complex, which in turn indicates reduced neural density. Laakso et
al., (2000) demonstrated reduced right hippocampal volume reductions
in violent offenders w/APD who were also early-onset alcoholics
compared to controls.
p. 281

violent severly abused offenders = temporal lobe functioning poor
Raine, Park et al. (2001), showed that violent offenders who had been
severely abused as children were more likely to show poor temporal
lobe functioning (http://en.wikipedia.org/wiki/Temporal_lobe) compared
to violent offenders lacking abuse. The dependent variable is brain
functioning. p. 285.

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