Dysfunctions of Medial and Lateral Orbitofrontal Cortex in Psychopathy

Psychopathy is a developmental disorder marked by emotional hypo-responsiveness and an increased risk for instrumental and reactive aggression. In this paper, it will be argued that the developmental origins of psychopathy do not lie in orbitofrontal cortex (OFC) dysfunction. This is because the key functional impairments seen in psychopathy are associated with amygdala damage, not with OFC damage. However, it will be argued that the role played by the integrated functioning of the amygdala and medial OFC in stimulus-reinforcement learning and decision making is disrupted in psychopathy. Impaired learning of stimulus-reinforcement associations and representation of reinforcement expectations are thought to underlie the impairments in socialization and appropriate decision making seen in psychopathy. It is suggested that the impairment in the role of medial OFC in prediction error signaling and the detection of contingency change may underlie the impairments in flexible behavioral change seen in psychopathy.

Instrumental learning and relearning in individuals with psychopathy and in patients with lesions involving the amygdala or orbitofrontal cortex

Previous work has shown that individuals with psychopathy are impaired on some forms of associative learning, particularly stimulus-reinforcement learning (Blair et al., 2004; Newman & Kosson, 1986). Animal work suggests that the acquisition of stimulus-reinforcement associations requires the amygdala (Baxter & Murray, 2002). Individuals with psychopathy also show impoverished reversal learning (Mitchell, Colledge, Leonard, & Blair, 2002). Reversal learning is supported by the ventrolateral and orbitofrontal cortex (Rolls, 2004). In this paper we present experiments investigating stimulus-reinforcement learning and relearning in patients with lesions of the orbitofrontal cortex or amygdala, and individuals with developmental psychopathy without known trauma. The results are interpreted with reference to current neurocognitive models of stimulus-reinforcement learning, relearning, and developmental psychopathy.

Psychopathy: cognitive and neural dysfunction

Psychopathy is a developmental disorder marked by emotional deficits and an increased risk for antisocial behavior. It is not equivalent to the diagnosis Antisocial Personality Disorder, which concentrates only on the increased risk for antisocial behavior and not a specific cause—ie, the reduced empathy and guilt that constitutes the emotional deficit. The current review considers data from adults with psychopathy with respect to the main cognitive accounts of the disorder that stress either a primary attention deficit or a primary emotion deficit. In addition, the current review considers data regarding the neurobiology of this disorder. Dysfunction within the amygdala's role in reinforcement learning and the role of ventromedial frontal cortex in the representation of reinforcement value is stressed. Data is also presented indicating potential difficulties within parts of temporal and posterior cingulate cortex. Suggestions are made with respect to why these deficits lead to the development of the disorder.

The pathology of social phobia is independent of developmental changes in face processing

OBJECTIVE

While social phobia in adolescence predicts the illness in adulthood, no study has directly compared the neural responses in social phobia in adults and adolescents. The authors examined neural responses to facial expressions in adults and adolescents with social phobia to determine whether the neural correlates of adult social phobia during face processing also manifest in adolescent social phobia.

METHOD

Blood-oxygen-level-dependent (BOLD) responses were compared in 39 medication-free participants with social phobia (25 adults and 14 adolescents) and 39 healthy comparison subjects (23 adults and 16 adolescents) matched on age, IQ, and gender. During fMRI scans, participants saw angry, fearful, and neutral expression stimuli while making a gender judgment.

RESULTS

Significant diagnosis-by-emotion interactions were observed within the amygdala and the rostral anterior cingulate cortex, as has previously been hypothesized. In these regions, both the adolescent and adult social phobia patients showed significantly increased BOLD responses relative to their respective age-matched comparison subjects, and there was no evidence of age-related modulation of between-group differences. These enhanced responses occurred specifically when viewing angry (rostral anterior cingulate cortex) and fearful (amygdala and rostral anterior cingulate cortex) expressions but not when viewing neutral expressions. In addition, the severity of social phobia was significantly correlated with the enhanced rostral anterior cingulate cortex response in the adults.

CONCLUSIONS

The neural correlates of adult social phobia during face processing also manifest in adolescents. Neural correlates that are observed in adult social phobia may represent the persistence of profiles established earlier in life rather than adaptive responses to such earlier perturbations or maturational changes. These cross-sectional observations might encourage longitudinal fMRI studies of adolescent social phobia.

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.

Can the fear recognition deficits associated with callous-unemotional traits be identified in early childhood?

INTRODUCTION

Callous-unemotional (CU) traits in the presence of conduct problems are associated with increased risk of severe antisocial behavior. Developmentally sensitive methods of assessing CU traits have recently been generated, but their construct validity in relation to neurocognitive underpinnings of CU has not been demonstrated. The current study sought to investigate whether the fear-specific emotion recognition deficits associated with CU traits in older individuals are developmentally expressed in young children as low concern for others and punishment insensitivity.

METHOD

A subsample of 337 preschoolers (mean age 4.8 years, SD = 0.8) who completed neurocognitive tasks was taken from a larger project of preschool psychopathology. Children completed an emotional recognition task in which they were asked to identify the emotional face from the neutral faces in an array. CU traits were assessed using the Low Concern (LC) and Punishment Insensitivity (PI) subscales of the Multidimensional Assessment Profile of Disruptive Behavior (MAP-DB), which were specifically designed to differentiate the normative misbehavior of early childhood from atypical patterns.

RESULTS

High LC, but not PI, scores were associated with a fear-specific deficit in emotion recognition. Girls were more accurate than boys in identifying emotional expressions but no significant interaction between LC or PI and sex was observed.

CONCLUSIONS

Fear recognition deficits associated with CU traits in older individuals were observed in preschoolers with developmentally defined patterns of low concern for others. Confirming that the link between CU-related impairments in empathy and distinct neurocognitive deficits is present in very young children suggests that developmentally specified measurement can detect the substrates of these severe behavioral patterns beginning much earlier than prior work. Exploring the development of CU traits and disruptive behavior disorders at very early ages may provide insights critical to early intervention and prevention of severe antisocial behavior.

Elevated amygdala responses to emotional faces in youths with chronic irritability or bipolar disorder

A major controversy in child psychiatry is whether bipolar disorder (BD) presents in children as severe, non-episodic irritability (operationalized here as severe mood dysregulation, SMD), rather than with manic episodes as in adults. Both classic, episodic BD and SMD are severe mood disorders characterized by deficits in processing emotional stimuli. Neuroimaging techniques can be used to test whether the pathophysiology mediating these deficits are similar across the two phenotypes. Amygdala dysfunction during face emotion processing is well-documented in BD, but little is known about amygdala dysfunction in chronically irritable youth. We compared neural activation in SMD (n = 19), BD (n = 19), and healthy volunteer (HV; n = 15) youths during an implicit face-emotion processing task with angry, fearful and neutral expressions. In the right amygdala, both SMD and BD exhibited greater activity across all expressions than HV. However, SMD and BD differed from each other and HV in posterior cingulate cortex, posterior insula, and inferior parietal lobe. In these regions, only SMD showed deactivation in response to fearful expressions, whereas only BD showed deactivation in response to angry expressions. Thus, during implicit face emotion processing, youth with BD and those with SMD exhibit similar amygdala dysfunction but different abnormalities in regions involved in information monitoring and integration.

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Youths with severe mood dysregulation (SMD), bipolar disorder (BD), controls.

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Implicit face-emotion processing fMRI task with angry, fearful, neutral emotions.

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In R amygdala, SMD and BD had greater activity across all expressions vs controls.

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In whole brain analysis SMD had decreased, BD increased activity vs. other groups.

The role of the amygdala and rostral anterior cingulate in encoding expected outcomes during learning

Successful passive avoidance learning is thought to require the use of learned stimulus-reinforcement associations to guide decision making [Baxter, M.G., Murray, E.A., 2002. The amygdala and reward. Nature Reviews. Neuroscience 3, 563-573]. The current experiment investigated the neural correlates of successful passive avoidance learning in 19 healthy adults. Behaviorally, subjects showed a distinct pattern of performance: early indiscriminate responding to stimuli (pre-criterion performance), followed by relatively rapid learning before a plateau of successful performance (post-criterion performance). Neural responses to post-criterion correct responses were compared with neural responses to both incorrect responses and pre-criterion correct responses. Post-criterion correct responding was associated with increased activation in regions including rostral anterior cingulate, insula, caudate, hippocampal regions, and the amygdala.

Callousness and affective face processing in adults: Behavioral and brain-potential indicators

The investigation of callous-unemotional (CU) traits has been central to contemporary research on child behavior problems, and served as the impetus for inclusion of a specifier for conduct disorder in the latest edition of the official psychiatric diagnostic system. Here, we report results from 2 studies that evaluated the construct validity of callousness as assessed in adults, by testing for affiliated deficits in behavioral and neural processing of fearful faces, as have been shown in youthful samples. We hypothesized that scores on an established measure of callousness would predict reduced recognition accuracy and diminished electocortical reactivity for fearful faces in adult participants. In Study 1, 66 undergraduate participants performed an emotion recognition task in which they viewed affective faces of different types and indicated the emotion expressed by each. In Study 2, electrocortical data were collected from 254 adult twins during viewing of fearful and neutral face stimuli, and scored for event-related response components. Analyses of Study 1 data revealed that higher callousness was associated with decreased recognition accuracy for fearful faces specifically. In Study 2, callousness was associated with reduced amplitude of both N170 and P200 responses to fearful faces. Current findings demonstrate for the first time that callousness in adults is associated with both behavioral and physiological deficits in the processing of fearful faces. These findings support the validity of the CU construct with adults and highlight the possibility of a multidomain measurement framework for continued study of this important clinical construct. (PsycINFO Database Record

Doing the right thing: A common neural circuit for appropriate violent or compassionate behavior

Humans have a considerable facility to adapt their behavior in a manner that is appropriate to social or societal context. A failure of this ability can lead to social exclusion and is a feature of disorders such as psychopathy and disruptive behavior disorder. We investigated the neural basis of this ability using a customized video game played by 12 healthy participants in an fMRI scanner. Two conditions involved extreme examples of context-appropriate action: shooting an aggressive humanoid assailant or healing a passive wounded person. Two control conditions involved carefully matched stimuli paired with inappropriate actions: shooting the person or healing the assailant. Surprisingly, the same circuit, including the amygdala and ventromedial prefrontal cortex, was activated when participants acted in a context-appropriate manner, whether being compassionate towards an injured conspecific or aggressive towards a violent assailant. The findings indicate a common system that guides behavioral expression appropriate to social or societal context irrespective of its aggressive or compassionate nature.

The contribution of ventrolateral and dorsolateral prefrontal cortex to response reversal

Studies investigating response reversal consistently implicate regions of medial and lateral prefrontal cortex when reinforcement contingencies change. However, it is unclear from these studies how these regions give rise to the individual components of response reversal, such as reinforcement value encoding, response inhibition, and response change. Here we report a novel instrumental learning task designed to determine whether regions implicated in processing reversal errors are uniquely involved in this process, or whether they play a more general role in representing response competition, reinforcement value, or punishment value in the absence of demands for response change. In line with previous findings, reversal errors activated orbitofrontal cortex, dorsomedial prefrontal cortex, ventrolateral prefrontal cortex, caudate, and dorsolateral prefrontal cortex. These regions also showed increased activity to errors in the absence of contingency changes. In addition, ventrolateral PFC, caudate, and dorsolateral PFC each exhibited increased activity following correct reversals. Activity in these regions was not significantly modulated by changes in reinforcement value that were not sufficient to make an alternative response advantageous. These data do not support punishment-processing or prepotent response inhibition accounts of ventrolateral prefrontal cortex function. Instead, they support recent conceptualizations of ventrolateral prefrontal cortex function that implicate this region in resolving response competition by manipulating the representation of either motor response options, or object features. These data also suggest that dorsolateral prefrontal cortex plays a role in reversal learning, probably through top down attentional control of object or reinforcement features when task demands increase.

A comparison of the effects of a beta-adrenergic blocker and a benzodiazepine upon the recognition of human facial expressions

RATIONALE

Accumulating evidence from neuropsychological and neuroimaging research suggests that facial expressions are processed by at least partially separable neurocognitive systems. Recent evidence implies that the processing of different facial expressions may also be dissociable pharmacologically by GABAergic and noradrenergic compounds, although no study has directly compared the two types of drugs.

OBJECTIVE

The present study therefore directly compared the effects of a benzodiazepine with those of a beta-adrenergic blocker on the ability to recognise emotional expressions.

METHODS

A double-blind, independent group design was used with 45 volunteers to compare the effects of diazepam (15 mg) and metoprolol (50 mg) with matched placebo. Participants were presented with morphed facial expression stimuli and asked to identify which of the six basic emotions (sadness, happiness, anger, disgust, fear and surprise) were portrayed. Control measures of mood, pulse rate and word recall were also taken.

RESULTS

Diazepam selectively impaired participants' ability to recognise expressions of both anger and fear but not other emotional expressions. Errors were mainly mistaking fear for surprise and disgust for anger. Metoprolol did not significantly affect facial expression recognition.

CONCLUSIONS

These findings are interpreted as providing further support for the suggestion that there are dissociable systems responsible for processing emotional expressions. The results may have implications for understanding why 'paradoxical' aggression is sometimes elicited by benzodiazepines and for extending our psychological understanding of the anxiolytic effects of these drugs.

Reward: empirical contribution. Temporal discounting and conduct disorder in adolescents

The current study examined temporal discounting (the decrease in subjective reward value as a function of increasing delay) in youths with conduct disorder (CD) and the extent to which this was modulated by level of psychopathic traits. In the temporal discounting task, participants were asked to choose between immediate rewards of varying values and a larger reward, held at a constant value ($10), whose receipt was delayed by different time intervals across trials (e.g., 7 days, 360 days). The level of immediate reward necessary for selection over the larger, delayed reward is the measure of temporal discounting. Forty-six youths (21 with CD and 25 healthy youths) participated in this study. Compared with healthy youths, youths with CD chose significantly smaller amounts of immediate reward rather than the larger future rewards. This was the case even in youths with CD without comorbid attention-deficit/hyperactivity disorder. However, level of psychopathic traits did not modulate temporal discounting in this sample. These results are discussed in terms of neurobiological models of CD and psychopathic traits.

Larger than life: humans' nonverbal status cues alter perceived size

BACKGROUND

Social dominance and physical size are closely linked. Nonverbal dominance displays in many non-human species are known to increase the displayer's apparent size. Humans also employ a variety of nonverbal cues that increase apparent status, but it is not yet known whether these cues function via a similar mechanism: by increasing the displayer's apparent size.

METHODOLOGY/PRINCIPAL FINDING

We generated stimuli in which actors displayed high status, neutral, or low status cues that were drawn from the findings of a recent meta-analysis. We then conducted four studies that indicated that nonverbal cues that increase apparent status do so by increasing the perceived size of the displayer. Experiment 1 demonstrated that nonverbal status cues affect perceivers' judgments of physical size. The results of Experiment 2 showed that altering simple perceptual cues can affect judgments of both size and perceived status. Experiment 3 used objective measurements to demonstrate that status cues change targets' apparent size in the two-dimensional plane visible to a perceiver, and Experiment 4 showed that changes in perceived size mediate changes in perceived status, and that the cue most associated with this phenomenon is postural openness.

CONCLUSIONS/SIGNIFICANCE

We conclude that nonverbal cues associated with social dominance also affect the perceived size of the displayer. This suggests that certain nonverbal dominance cues in humans may function as they do in other species: by creating the appearance of changes in physical size.

Dissociable roles of ventromedial prefrontal cortex (vmPFC) and rostral anterior cingulate cortex (rACC) in value representation and optimistic bias

Optimistic bias (OB) is seen when individuals underestimate their probability of experiencing negative life events and overestimate their probability of experiencing positive life events. A reduced OB has been linked with increased depression symptoms. However, given the relevance of this information to mood and anxiety disorders, little is currently known regarding the neurobiology of OB. In the current study, we examine the neural basis of OB in healthy individuals (n=33) during probability estimation of future positive and negative events occurring to themselves relative to other, comparable individuals. In line with previous work, subjects showed significant OB; they considered themselves significantly more likely to experience future positive and significantly less likely to experience future negative events relative to comparable others. Positive, relative to negative events, un-modulated by subjects' probability estimates, were associated with significantly greater activity within the ventromedial prefrontal cortex (vmPFC) and posterior cingulate cortex (PCC). Moreover, responses within both regions to positive events negatively related to the healthy subjects' self reports of depression symptoms. However, there was no significant modulation of activity in either region by the subject's OB, objectified as the level to which they thought the event was more likely [positive events] or less likely [negative events] to occur to them relative to comparable others. In contrast, activity within the rostral anterior cingulate cortex (rACC) was positively modulated by OB for positive events and activity within the anterior insula and dorsomedial prefrontal cortex (dmPFC) was negatively modulated by OB for negative events. However, there was no significant relationship between responsiveness within these regions and self reports of depression symptoms. The data are discussed with reference to current models of vmPFC, rACC and anterior insula functioning.

Impaired recognition of fear facial expressions in 5-HTTLPR S-polymorphism carriers following tryptophan depletion

RATIONALE

Genotype at the 5' promoter region (5-HTTLPR) of the serotonin transporter has been implicated in moderating the effects of acute tryptophan depletion on neurocognitive functioning. Acute tryptophan depletion has been associated with the processing of fear-relevant cues, such as emotional expressions, but the effect of genotype at the 5-HTTLPR has not been assessed.

OBJECTIVE

The present study investigated the effects of acute tryptophan depletion on the recognition of standardized facial expressions of emotions in healthy volunteers classified as ll homozygotes or s carriers.

MATERIALS AND METHODS

A double-blind between-groups design was used with volunteers randomly selected to ingest capsules containing an amino acid mixture specifically lacking tryptophan, or placebo capsules containing lactose. 5 h after capsule ingestion, subjects were required to identify anger, disgust, fear, happiness, sadness, and surprise expressions that progressed from neutral to each full emotional expression in 5% steps.

RESULTS

Tryptophan depletion significantly impaired the recognition of fearful facial expressions in s carriers but not ll homozygotes. This impairment was specific to fear expressions. No significant differences in the recognition of other expressions were found. Free tryptophan levels were correlated with fear recognition in s carriers but not ll homozygotes.

CONCLUSIONS

The effects of acute tryptophan depletion on the processing of emotional expressions varies as a function of genotype at the 5-HTTLPR. Depletion impairs the recognition of fear in s carriers but not ll homozygotes. This finding reinforces the importance of considering genotype when assessing the behavioral effects of pharmacologic modulation.

Callous-unemotional traits modulate the neural response associated with punishing another individual during social exchange: a preliminary investigation

The current study examined whether Callous-Unemotional (CU) traits, a core component of psychopathy, modulate neural responses of participants engaged in a social exchange game. In this task, participants were offered an allocation of money and then given the chance to punish the offerer. Twenty youth participated and responses to both offers and the participant's punishment (or not) of these offers were examined. Increasingly unfair offers were associated with increased dorsal anterior cingulate cortex (dACC) activity but this responsiveness was not modulated by CU traits. Increasing punishment of unfair offers was associated with increased dACC and anterior insula activity and this activity was modulated by CU traits. Higher CU trait participants showed a weaker association between activity and punishment level. These data suggest that CU traits are associated with appropriate expectations of other individual's normative behavior but weaker representations of such information when guiding behavior of the self.

Adolescents show differential dysfunctions related to Alcohol and Cannabis Use Disorder severity in emotion and executive attention neuro-circuitries

Alcohol and cannabis are two substances that are commonly abused by adolescents in the United States and which, when abused, are associated with negative medical and psychiatric outcomes across the lifespan. These negative psychiatric outcomes may reflect the detrimental impact of substance abuse on neural systems mediating emotion processing and executive attention. However, work indicative of this has mostly been conducted either in animal models or adults with Alcohol and/or Cannabis Use Disorder (AUD/CUD). Little work has been conducted in adolescent patients. In this study, we used the Affective Stroop task to examine the relationship in 82 adolescents between AUD and/or CUD symptom severity and the functional integrity of neural systems mediating emotional processing and executive attention. We found that AUD symptom severity was positively related to amygdala responsiveness to emotional stimuli and negatively related to responsiveness within regions implicated in executive attention and response control (i.e., dorsolateral prefrontal cortex, anterior cingulate cortex, precuneus) as a function of task performance. In contrast, CUD symptom severity was unrelated to amygdala responsiveness but positively related to responsiveness within regions including precuneus, posterior cingulate cortex, and inferior parietal lobule as a function of task performance. These data suggest differential impacts of alcohol and cannabis abuse on the adolescent brain.

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Alcohol and cannabis are the most widely abused substances by adolescents.

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AUDIT scores are related to amygdala hyperactivity to emotional stimuli.

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AUDIT scores are related to hypoactivity in executive attention neuro-circuitry.

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CUDIT scores are related to hyperactivity in executive attention neuro-circuitry.

The relationship between large cavum septum pellucidum and antisocial behavior, callous-unemotional traits and psychopathy in adolescents

BACKGROUND

The presence of a large cavum septum pellucidum (CSP) has been previously associated with antisocial behavior/psychopathic traits in an adult community sample.

AIMS

The current study investigated the relationship between a large CSP and symptom severity in disruptive behavior disorders (DBD; conduct disorder and oppositional defiant disorder).

METHOD

Structural MRI scans of youth with DBDs (N = 32) and healthy comparison youth (N = 27) were examined for the presence of a large CSP and if this was related to symptom severity.

RESULTS

Replicating previous results, a large CSP was associated with DBD diagnosis, proactive aggression, and level of psychopathic traits in youth. However, the presence of a large CSP was unrelated to aggression or psychopathic traits within the DBD sample.

CONCLUSIONS

Early brain mal-development may increase the risk of a DBD diagnosis, but does not mark a particularly severe form of DBD within patients receiving these diagnoses.

Common regions of dorsal anterior cingulate and prefrontal-parietal cortices provide attentional control of distracters varying in emotionality and visibility

Top-down attentional control is necessary to ensure successful task performance in the presence of distracters. Lateral prefrontal cortex, parietal cortex and anterior cingulate cortex have been previously implicated in top-down attentional control. However, it is unclear whether these regions are engaged independent of distracter type or whether, as has been suggested for anterior cingulate cortex, different regions provide attentional control over emotional versus other forms of salient distracter. In the current task, subjects viewed targets that were preceded by distracters that varied in both emotionality and visibility. We found that behaviorally, the presence of preceding distracters significantly interfered with target judgment. At the neural level, increases in the emotional and visual saliency of distracters were both associated with increased activity in proximal regions of prefrontal, parietal and cingulate cortex. Moreover, a conjunction analysis indicated considerable overlap in the regions of prefrontal, parietal cortex and anterior cingulate cortex responding to distracters of increased emotionality and visibility.

Psychopathic traits from an RDoC perspective

In this review an RDoC approach is applied to psychopathic traits. Two core neuro-cognitive systems relevant to the emergence of psychopathic traits are considered. These are the response to other individuals' emotional displays and reinforcement-based decision-making.

The neural substrates of action identification

Mentalization is the process by which an observer views a target as possessing higher cognitive faculties such as goals, intentions and desires. Mentalization can be assessed using action identification paradigms, in which observers choose mentalistic (goals-focused) or mechanistic (action-focused) descriptions of targets' actions. Neural structures that play key roles in inferring goals and intentions from others' observed or imagined actions include temporo-parietal junction, ventral premotor cortex and extrastriate body area. We hypothesized that these regions play a role in action identification as well. Data collected using functional magnetic resonance imaging (fMRI) confirmed our predictions that activity in ventral premotor cortex and middle temporal gyrus near the extrastriate body area varies both as a function of the valence of the target and the extent to which actions are identified as goal-directed. In addition, the inferior parietal lobule is preferentially engaged when participants identify the actions of mentalized targets. Functional connectivity analyses suggest support from other regions, including the medial prefrontal cortex and amygdala, during mentalization. We found correlations between action identification and Autism Quotient scores, suggesting that understanding the neural correlates of action identification may enhance our understanding of the underpinnings of essential social cognitive processes.

Turning a deaf ear to fear: impaired recognition of vocal affect in psychopathic individuals

The processing of emotional expressions is fundamental for normal socialization and interaction. Reduced responsiveness to the expressions of sadness and fear has been implicated in the development of psychopathy (R. J. R. Blair, 1995). The current study investigates the ability of adult psychopathic individuals to process vocal affect. Psychopathic and nonpsychopathic adults, defined by the Hare Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991), were presented with neutral words spoken with intonations conveying happiness, disgust, anger, sadness, and fear and were asked to identify the emotion of the speaker on the basis of prosody. The results indicated that psychopathic inmates were particularly impaired in the recognition of fearful vocal affect. These results are interpreted with reference to the low-fear and violence inhibition mechanism models of psychopathy.

Executive attention control and emotional responding in attention-deficit/hyperactivity disorder--A functional MRI study

Background

There are suggestions that patients with attention-deficit/hyperactivity disorder (ADHD) show impairment in executive attention control and emotion regulation. This study investigated emotion regulation as a function of the recruitment of executive attention in patients with ADHD.

Methods

Thirty-five healthy children/adolescents (mean age = 13.91) and twenty-six children/adolescents with ADHD (mean age = 14.53) participated in this fMRI study. They completed the affective Stroop paradigm viewing positive, neutral and negative images under varying cognitive loads. A 3-way ANOVA (diagnosis-by-condition-by-emotion) was conducted on the BOLD response data. Following this, 2 3-way ANOVAs (diagnosis-by-condition-by-emotion) were applied to context-dependent psychophysiological interaction (gPPI) analyses generated from a dorsomedial frontal cortex and an amygdala seed (identified from the BOLD response ANOVA main effects of condition and emotion respectively).

Results

A diagnosis-by-condition interaction within dorsomedial frontal cortex revealed reduced recruitment of dorsomedial frontal cortex as a function of increased task demands in the children/adolescents with ADHD relative to healthy children/adolescents. The level of reduction in recruitment of dorsomedial frontal cortex was significantly correlated with symptom severity (total and hyperactivity) measured by Conner's Parent Report Scale in the children/adolescents with ADHD. In addition, analysis of gPPI data from a dorsomedial frontal cortex seed revealed significant diagnosis-by-condition interactions within lateral frontal cortex; connectivity between dorsomedial frontal cortex and lateral frontal cortex was reduced in the patients with ADHD relative to comparison youth during congruent and incongruent task trials relative to view trials. There were no interactions of group, or main effect of group, within the amygdala in the BOLD response ANOVA (though children/adolescents with ADHD showed increased responses to positive images within temporal cortical regions during task trials; identified by the diagnosis-by-condition-by-emotion interaction). However, analysis of gPPI data from an amygdala seed revealed decreased connectivity between amygdala and lentiform nucleus in the presence of emotional stimuli in children/adolescents with ADHD (diagnosis-by-emotion interaction).

Conclusion

The current study demonstrated disrupted recruitment of regions implicated in executive function and impaired connectivity within those regions in children/adolescents with ADHD. There were also indications of heightened representation of emotional stimuli in patients with ADHD. However, as the findings were specific for positive stimuli, the suggestion of a general failure in emotion regulation in ADHD was not supported.

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ADHD showed decreased dorsomedial frontal cortex activity with increased cognitive demand.

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Decreased dorsomedial frontal cortex activity was correlated with symptom severity of ADHD.

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Connectivity of dorsomedial frontal cortex–lateral frontal cortex was compromised in ADHD.

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ADHD showed increased activities in emotional responding areas to positive emotional stimuli.

Serotonin transporter genotype (5-HTTLPR) predicts utilitarian moral judgments

Background

The psychological and neurobiological processes underlying moral judgment have been the focus of extensive recent research. Here we show that serotonin transporter (5-HTTLPR) genotype predicts responses to moral dilemmas featuring foreseen harm to an innocent.

Methodology/Principal Findings

Participants in this study judged the acceptability of actions that would unintentionally or intentionally harm an innocent victim in order to save others' lives. An analysis of variance revealed a genotype × scenario interaction, F(2, 63) = 4.52, p = .02. Results showed that, relative to long allele homozygotes (LL), carriers of the short (S) allele showed particular reluctance to endorse utilitarian actions resulting in foreseen harm to an innocent individual. LL genotype participants rated perpetrating unintentional harm as more acceptable (M = 4.98, SEM = 0.20) than did SL genotype participants (M = 4.65, SEM = 0.20) or SS genotype participants (M = 4.29, SEM = 0.30). No group differences in moral judgments were observed in response to scenarios featuring intentional harm.

Conclusions/Significance

The results indicate that inherited variants in a genetic polymorphism that influences serotonin neurotransmission influence utilitarian moral judgments as well. This finding is interpreted in light of evidence that the S allele is associated with elevated emotional responsiveness.