Psychopathy and cerebral asymmetry in semantic processing

Phonological processing in psychopathic offenders

Recent research has demonstrated that psychopathic offenders exhibit dynamic cognitive and behavioral deficits on a variety of lab tasks that differentially activate left hemisphere resources. The Left Hemisphere Activation (LHA) hypothesis is a cognitive perspective that aims to address these deficits by conceptualizing psychopathy as a disorder in which behavior and cognitive processing change dynamically as a function of the differential taxation of left hemisphere resources. This study aimed to investigate whether psychopathic traits are associated with electrophysiological anomalies under conditions that place differential demands on left hemisphere language processing systems. We examined in a sample of 43 incarcerated indivdiuals the evocation of the N320, an event-related potential (ERP) elicited by nontarget stimuli during a phonological/phonetic decision task that has been shown to elicit greater activation and cognitive processing within the left hemisphere than the right hemisphere. Findings for a subsample of 18 offenders low in psychopathic traits were generally consistent with previous findings in healthy individuals, suggesting similar electrophysiological activity during phonological processing. However, psychopathic traits impacted the amplitude of the N320. Higher levels of psychopathic traits were associated with reduced left-lateralization in phonological processing as well as enhanced ERP differentiation between pronounceable and nonpronounceable stimuli. These findings provide physiological evidence of a relationship between psychopathic traits and anomalous language processing at the phonological level of word processing.

Personality and psychopathy of males with a history of early criminal behaviour

Data from three personality inventories—the Eysenck Personality Questionnaire (EPQ) including an Impulsivity scale from the IVE inventory, a short version of two Chapman scales, and the Karolinska Scales of Personality (KSP)—were studied for a group of 199 male subjects (age range 32–40 years) subdivided ( 1 ) according to the level of Psychopathy Check List (PCL) scores at adult age and (2) according to criminal activity during the age period of 11–14 years. Intelligence scores from the age of 11–14 and ratings of mental health, both from age 11–14 and from adult life, were examined in relation to the PCL and early criminal groupings, respectively. Furthermore, a dimensional description of the PCL was performed on the total sample. Subjects with high PCL scores formed a risk group for developing ‘disinhibitory psychopathology’. They manifested a personality pattern of markedly high impulsivity, monotony avoidance, and psychoticism, and low socialization in combination with high proneness to somatic anxiety. A significant quadratic trend was found for PCL group on the IVE Impulsiveness scale. The early ‘high criminal’ and early ‘low criminal’ groups had significantly lower socialization scores and higher PCL impulsivity item scores than the control group indicating ‘vulnerability’ for developing psychosocial disorders. Furthermore, the early ‘high criminal’ group displayed higher scores on the three PCL factors obtained, denoted ‘Sensation seeking and impulsivity’, ‘Callousness/lack of deep emotions’, and ‘Narcissistic appearance/manipulative’. The results are discussed in terms of usefulness of a classification according to PCL scores, as compared with early criminal activity, when focusing on risk subjects for disinhibitory tendencies.

Untangling Intelligence, Psychopathy, Antisocial Personality Disorder, and Conduct Problems: A Meta–Analytic Review

Substantial research has investigated the association between intelligence and psychopathic traits. The findings to date have been inconsistent and have not always considered the multidimensional nature of psychopathic traits. Moreover, there has been a tendency to confuse psychopathy with other closely related, clinically significant disorders. The current study represents a meta–analysis conducted to evaluate the direction and magnitude of the association of intelligence with global psychopathy, as well as its factors and facets, and related disorders (i.e. antisocial personality disorder, conduct disorder, and oppositional defiant disorder). Our analyses revealed a small, significant, negative relationship between intelligence and total psychopathy ( r = −.07, p = .001). Analysis of factors and facets found differential associations, including both significant positive (e.g. interpersonal facet) and negative (e.g. affective facet) associations, further affirming that psychopathy is a multidimensional construct. Additionally, intelligence was negatively associated with antisocial personality disorder ( r = −.13, p = .001) and conduct disorder ( r = −.13, p = .001) but positively with oppositional defiant disorder ( r = .06, p = .001). There was significant heterogeneity across studies for most effects, but the results of moderator analyses were inconsistent. Finally, bias analyses did not find significant evidence for publication bias or outsized effects of outliers. © 2019 European Association of Personality Psychology

Relationships between trait impulsivity and cognitive control: the effect of attention switching on response inhibition and conflict resolution

This study examined the relationship between trait impulsivity and cognitive control, as measured by the Barratt Impulsiveness Scale (BIS) and a focused attention dichotic listening to words task, respectively. In the task, attention was manipulated in two attention conditions differing in their cognitive control demands: one in which attention was directed to one ear at a time for a whole block of trials (blocked condition) and another in which attention was switched pseudo-randomly between the two ears from trial to trial (mixed condition). Results showed that high impulsivity participants exhibited more false alarm and intrusion errors as well as a lesser ability to distinguish between stimuli in the mixed condition, as compared to low impulsivity participants. In the blocked condition, the performance levels of the two groups were comparable with respect to these measures. In addition, total BIS scores were correlated with intrusions and laterality index in the mixed but not the blocked condition. The findings suggest that high impulsivity individuals may be less prone to attentional difficulties when cognitive load is relatively low. In contrast, when attention switching is involved, high impulsivity is associated with greater difficulty in inhibiting responses and resolving cognitive conflict than is low impulsivity, as reflected in error-prone information processing. The conclusion is that trait impulsivity in a non-clinical population is manifested more strongly when attention switching is required than during maintained attention. This may have important implications for the conceptualization and treatment of impulsivity in both non-clinical and clinical populations.

Neurocriminology

In the past several decades there has been an explosion of research into the biological correlates to antisocial behavior. This chapter reviews the state of current research on the topic, including a review of the genetics, neuroimaging, neuropsychological, and electrophysiological studies in delinquent and antisocial populations. Special attention is paid to the biopsychosocial model and gene-environment interactions in producing antisocial behavior.

The neurobiology of psychopathy: a neurodevelopmental perspective

We provide an overview of the neurobiological underpinnings of psychopathy. Cognitive and affective-emotional processing deficits are associated with abnormal brain structure and function, particularly the amygdala and orbitofrontal cortex. There is limited evidence of lower cortisol levels being associated with psychopathic personality. Initial developmental research is beginning to suggest that these neurobiological processes may have their origins early in life. Findings suggest that psychopathic personality may, in part, have a neurodevelopmental basis. Future longitudinal studies delineating neurobiological correlates of the analogues of interpersonal-affective and antisocial features of psychopathy in children are needed to further substantiate a neurodevelopmental hypothesis of psychopathy.

Evidence of deviant emotional processing in psychopathy: a FMRI case study

In this case-report we describe a prototypical criminal psychopath by clinical characteristics and functional magnetic resonance imaging (fMRI). To study emotional disability in psychopathy we compared fMRI-BOLD (blood oxygen level dependent) responses to healthy controls. In a block-design subjects were exposed to drawings of facial expressions alternated with scrambled drawings. Exposure to facial expressions activated brain regions of older origin in the psychopath, whereas all activated regions in controls were neocortical. Our findings support the notion that the processing of emotional stimuli in psychopathy is atypical.

Testing neuropsychological hypotheses for cognitive deficits in psychopathic criminals: a study of global-local processing

Competing hypotheses about neuropsychological mechanisms underlying psychopathy are seldom examined in the same study. We tested the left hemisphere activation hypothesis and the response modulation hypothesis of psychopathy in 172 inmates completing a global-local processing task under local bias, global bias, and neutral conditions. Consistent with the left hemisphere activation hypothesis, planned comparisons showed that psychopathic inmates classified local targets more slowly than nonpsychopathic inmates in a local bias condition and exhibited a trend toward similar deficits for global targets in this condition. However, contrary to the response modulation hypothesis, psychopaths were no slower to respond to local targets in a global bias condition. Because psychopathic inmates were not generally slower to respond to local targets, results are also not consistent with a general left hemisphere dysfunction account. Correlational analyses also indicated deficits specific to conditions presenting most targets at the local level initially. Implications for neuropsychological conceptualizations of psychopathy are considered.

They know the words, but not the music: Affective and semantic priming in individuals with psychopathy

Previous work has indicated dysfunctional affect-language interactions in individuals with psychopathy through use of the lexical decision task. However, it has been uncertain as to whether these deficits actually reflect impaired affect-language interactions or a more fundamental deficit in general semantic processing. In this study, we examined affective priming and semantic priming (dependent measures were reaction times and error rates) in individuals with psychopathy and comparison individuals, classified according to the psychopathy checklist revised (PCL-R) [Hare, R.D., 1991. The Hare Psychopathy Checklist-Revised. Multi-Health Systems, Toronto, Ont] Individuals with psychopathy showed significantly less affective priming relative to comparison individuals. In contrast, the two groups showed comparable levels of semantic priming. The results are discussed with reference to current models of psychopathy.

Forming, switching, and maintaining mental sets among psychopathic offenders during verbal and nonverbal tasks: another look at the left-hemisphere activation hypothesis

Three hypotheses for cognitive deficits among psychopaths were tested: executive dysfunction, left hemisphere activation, and an interaction between the two. Twenty-one psychopathic and 23 nonpsychopathic criminal offenders identified with the Hare Psychopathy Checklist-Revised participated in verbal and visual-spatial tasks during which the level of executive processing demands was manipulated. Consistent with prior research, psychopathic offenders made more errors than controls, but only during the verbal task and only on trials with high executive demand. Within those trials, most errors occurred when set-maintenance demands were the highest. No response latency differences between groups were found.

A cognitive neuroscience perspective on psychopathy: evidence for paralimbic system dysfunction

Psychopathy is a complex personality disorder that includes interpersonal and affective traits such as glibness, lack of empathy, guilt or remorse, shallow affect, and irresponsibility, and behavioral characteristics such as impulsivity, poor behavioral control, and promiscuity. Much is known about the assessment of psychopathy; however, relatively little is understood about the relevant brain disturbances. The present review integrates data from studies of behavioral and cognitive changes associated with focal brain lesions or insults and results from psychophysiology, cognitive psychology and cognitive and affective neuroscience in health and psychopathy. The review illustrates that the brain regions implicated in psychopathy include the orbital frontal cortex, insula, anterior and posterior cingulate, amygdala, parahippocampal gyrus, and anterior superior temporal gyrus. The relevant functional neuroanatomy of psychopathy thus includes limbic and paralimbic structures that may be collectively termed 'the paralimbic system'. The paralimbic system dysfunction model of psychopathy is discussed as it relates to the extant literature on psychopathy.

Neuropsychological implications of selective attentional functioning in psychopathic offenders

Several core characteristics of the psychopathic personality disorder (i.e., impulsivity, failure to attend to interpersonal cues) suggest that psychopaths suffer from disordered attention. However, there is mixed evidence from the cognitive literature as to whether they exhibit superior or deficient selective attention, which has led to the formation of several distinct theories of attentional functioning in psychopathy. The present experiment investigated participants' abilities to purposely allocate attentional resources on the basis of auditory or visual linguistic information and directly tested both theories of deficient or superior selective attention in psychopathy. Specifically, 91 male inmates at a county jail were presented with either auditory or visual linguistic cues (with and without distractors) that correctly indicated the position of an upcoming visual target in 75% of the trials. The results indicated that psychopaths did not exhibit evidence of superior selective attention in any of the conditions but were generally less efficient in shifting attention on the basis of linguistic cues, especially in regard to auditory information. Implications for understanding psychopaths' cognitive functioning and possible neuropsychological deficits are addressed.

State-dependent executive deficits among psychopathic offenders

Three hypotheses for cognitive deficits among psychopaths were tested: Response modulation, left hemisphere activation, and an interaction between the 2. Twenty-six psychopathic and 32 nonpsychopathic criminal offenders identified with the Hare Psychopathy Checklist-Revised were randomly assigned to left- and right-hemisphere activation groups. An auditory processing task was administered, such that the ability to classify nonverbal auditory signals and the ability to manage subgoals were assessed under left- and right-hemisphere activation conditions. The results showed that psychopaths' information processing in general, including response modulation, was deleteriously affected by left-hemisphere activation, supporting 2 of the 3 hypotheses tested. These results offer an explanation for inconsistent findings of executive deficits among psychopaths.

Temporal lobe abnormalities in semantic processing by criminal psychopaths as revealed by functional magnetic resonance imaging

We tested the hypothesis that psychopathy is associated with abnormalities in semantic processing of linguistic information. Functional magnetic resonance imaging (fMRI) was used to elucidate and characterize the neural architecture underlying lexico-semantic processes in criminal psychopathic individuals and in a group of matched control participants. Participants performed a lexical decision task in which blocks of linguistic stimuli alternated with a resting baseline condition. In each lexical decision block, the stimuli were either concrete words and pseudowords or abstract words and pseudowords. Consistent with our hypothesis, psychopathic individuals, relative to controls, showed poorer behavioral performance for processing abstract words. Analysis of the fMRI data for both groups indicated that processing of word stimuli, compared with the resting baseline condition, was associated with neural activation in bilateral fusiform gyrus, anterior cingulate, left middle temporal gyrus, right posterior superior temporal gyrus, and left and right inferior frontal gyrus. Analyses confirmed our prediction that psychopathic individuals would fail to show the appropriate neural differentiation between abstract and concrete stimuli in the right anterior temporal gyrus and surrounding cortex. The results are consistent with other studies of semantic processing in psychopathy and support the theory that psychopathy is associated with right hemisphere abnormalities for processing conceptually abstract material.

Temporal lobe abnormalities in semantic processing by criminal psychopaths as revealed by functional magnetic resonance imaging

We tested the hypothesis that psychopathy is associated with abnormalities in semantic processing of linguistic information. Functional magnetic resonance imaging (fMRI) was used to elucidate and characterize the neural architecture underlying lexico-semantic processes in criminal psychopathic individuals and in a group of matched control participants. Participants performed a lexical decision task in which blocks of linguistic stimuli alternated with a resting baseline condition. In each lexical decision block, the stimuli were either concrete words and pseudowords or abstract words and pseudowords. Consistent with our hypothesis, psychopathic individuals, relative to controls, showed poorer behavioral performance for processing abstract words. Analysis of the fMRI data for both groups indicated that processing of word stimuli, compared with the resting baseline condition, was associated with neural activation in bilateral fusiform gyrus, anterior cingulate, left middle temporal gyrus, right posterior superior temporal gyrus, and left and right inferior frontal gyrus. Analyses confirmed our prediction that psychopathic individuals would fail to show the appropriate neural differentiation between abstract and concrete stimuli in the right anterior temporal gyrus and surrounding cortex. The results are consistent with other studies of semantic processing in psychopathy and support the theory that psychopathy is associated with right hemisphere abnormalities for processing conceptually abstract material.

Stroop tasks reveal abnormal selective attention among psychopathic offenders

Selective attention among offenders with psychopathy was investigated using 3 Stroop paradigms: a standard color-word (CW) Stroop, a picture-word (PW) Stroop, and a color-word Stroop in which the word and color were spatially separated (separated CW). Consistent with "overselective" attention, offenders with psychopathy displayed reduced Stroop interference on the separated CW and PW tasks relative to offenders who were not psychopathic. However, offenders with psychopathy displayed normal Stroop interference on the standard CW Stroop. Further, the reduced interference of offenders with psychopathy on the separated CW Stroop was accompanied by normal facilitation. These findings suggest a circumscribed attentional deficit in psychopathy that hinders the use of unattended information that is (a) not integrated with deliberately attended information and (b) not compatible with current goal-directed behavior.

Commission error rates on a continuous performance test are related to deficits measured by the Benton Visual Retention Test

This study is one in a series investigating the relationship between impulsive behavior on a Continuous Performance Test (i.e., the Immediate and Delayed Memory Task) and other cognitive deficits measured by clinical instruments. Forty-two adolescents were selected for two groups, controls and hospitalized patients with disruptive behavior disorders. Each adolescent completed the Immediate and Delayed Memory Task and the Benton Visual Retention Test. Our main findings were that, even when controlling for IQ, the Immediate and Delayed Memory Task commission errors were associated with adverse Benton performance, but only in the patient group. These results may be explained by a shared association between processes of impulsivity and other deficits of executive control that may interfere with successful performance of the Benton.

Deficient response modulation and emotion processing in low-anxious Caucasian psychopathic offenders: results from a lexical decision task

The clinical and research literatures on psychopathy have identified an emotion paradox: Psychopaths display normal appraisal but impaired use of emotion cues. Using R. D. Hare's (1991) Psychopathy Checklist-Revised and the G. S. Welsh Anxiety Scale (1956), the authors identified low-anxious psychopaths and controls and examined predictions concerning their performance on a lexical-decision task. Results supported all the predictions: (a) low-anxious psychopaths appraised emotion cues as well as controls; (b) their lexical decisions were relatively unaffected by emotion cues; (c) their lexical decisions were relatively unaffected by affectively neutral word-frequency cues; and (d) their performance deficits were specific to conditions involving right-handed responses. The authors propose that deficient response modulation may underlie both the emotional and cognitive deficits associated with low-anxious psychopaths.

Left-hemisphere activation and deficient response modulation in psychopaths

Psychopathic offenders have difficulty processing contextual or secondary cues once they have initiated goal-directed behavior or allocated attention to a primary task. To test the hypothesis that this deficit in response modulation is specific to conditions in which psychopaths' left-hemisphere resources are engaged, we administered a serial recall task to 21 incarcerated psychopaths and 21 control subjects. Subjects were instructed to memorize eight words that were presented one at a time, each in one of the four corners of the visual display. Subjects' primary task was to recall the words in serial order. Then, without forewarning, they were asked to recall the words' locations. As predicted, psychopaths performed as well as control subjects in recalling words from the left and right spatial fields, but recalled significantly fewer locations from the right spatial field. Thus, psychopaths' deficient response modulation was specific to conditions in which their left-hemisphere resources were actively engaged.

Reduced P300 responses in criminal psychopaths during a visual oddball task

BACKGROUND

Clinicians have long recognized that psychopaths show deficits in cognitive function, but there have been few experimental studies exploring these deficits. We present here the first in a series of event-related potential (ERP) experiments designed to elucidate and characterize the neural correlates of cognitive processes of psychopaths.

METHODS

We recorded ERPs from a topographic array from 11 psychopathic and 10 nonpsychopathic prison inmates, assessed with the Hare Psychopathy Checklist-Revised, during performance of a visual oddball task. ERPs to target (25% of trials) and nontarget (75% of trials) visual stimuli were analyzed.

RESULTS

Consistent with previous research, there were no group differences in the latency or amplitude of the ERPs for the nontarget stimuli. For nonpsychopaths, the P300 amplitude was larger when elicited by the target stimuli than when elicited by the nontarget stimuli. In contrast, psychopaths failed to show reliable P300 amplitude differences between the target and nontarget conditions. Psychopaths had a smaller amplitude P300 to target stimuli than did nonpsychopaths. In addition, the amplitude of the P300 was less lateralized in psychopaths than in nonpsychopaths. Psychopaths also had a larger centrofrontal negative wave (N550) during the target condition than did nonpsychopaths.

CONCLUSIONS

The results of this study indicate that there are substantial differences between psychopaths and others in the processing of even simple cognitive tasks and provide support for information processing models of psychopathy.

Psychopathy--a neurobiological perspective

BACKGROUND

Diagnostic and conceptual issues relating to psychopathy are widely debated, but advances in our understanding of the aetiology are limited.

METHOD

A PSYCHLIT computerised database search of publications covering five decades was supplemented by tracing back through references from existing review work.

RESULTS

Over 200 articles were extracted, and 95 were selected for review.

CONCLUSIONS

It is timely to evaluate the rôle of brain dysfunction. Biological determinants are under-researched and the lack of consistency in operational definitions in published research precludes anything more than tentative conclusions about the genetic, biochemical or electrophysiological correlates of psychopathy and antisocial behaviour. A multi-modal research programme is required in the search for a comprehensive model of psychopathy that can guide both research efforts and clinical interventions.

Relationship between CNV asymmetries and individual differences in cognitive performance, personality and gender

This study used verbal and spatial variants of a cognitive 'match/mismatch' paradigm to explore relationships between functional brain asymmetries and individual differences in cognitive performance, personality and gender. Contingent negative variation (CNV) elicited in the 'match/mismatch' paradigm was recorded from central (Cz, C3 and C4) derivations in two male and one female samples. Results indicated gender differences in both the degree and direction of CNV asymmetries. Males showed a left hemisphere asymmetry in the verbal task and a right hemisphere asymmetry in the spatial task, with significant laterality (C3-C4) differences between tasks across the foreperiod. Females showed a left hemisphere asymmetry in both tasks with laterality differences between tasks confined to the early part of the foreperiod. CNV amplitude in the verbal task correlated with verbal memory performance and verbal I.Q. CNV amplitude in the spatial task correlated with visuospatial memory performance. Social extraversion was associated with greater left-hemisphere asymmetry in both tasks, while behavioural extraversion was associated with left-hemisphere asymmetry in the verbal task only, and with smaller verbal than spatial CNVs.

Abnormal processing of affective words by psychopaths

We tested the hypothesis that psychopathy is associated with abnormal processing of affective verbal material. Criminal psychopaths and nonpsychopaths, defined by the Psychopathy Checklist, performed a lexical decision task ("Is it a word or not?") while we recorded reaction time and event-related potentials in response to letter-strings consisting of affective and neutral words and pronounceable nonwords. On the assumption that they do not make efficient use of affective information, our primary prediction was that psychopaths would show less behavioral and event-related potential differentiation between affective and neutral words than would nonpsychopaths. The results were in accordance with this prediction. The lexical decisions of nonpsychopaths were significantly faster, and relevant event-related potential components were significantly larger, to affective words than to neutral words. In sharp contrast, psychopaths failed to show reaction time facilitation or larger amplitude event-related potentials to affective words. We suggest that psychopaths extract less information from affective words than do other individuals. Possible implications of these and related findings for understanding the behavior of psychopaths are discussed.

Psychopathy and P3 amplitude: a commentary on Raine

Raine (1989) reviewed the literature on event-related potentials (ERPs) in psychopathic adults and antisocial adolescents and concluded that findings support an extended sensation-seeking model of psychopathy. Specifically, he suggested that P3 findings were indicative of unusually enhanced attentional processing in psychopaths. It will be argued in this paper that evidence from recent ERP studies is insufficient to challenge notions of information processing deficit in psychopathy, and that an extended 'cortical immaturity' hypothesis can better account for psychopathic behaviour than the model proposed by Raine.