Alexithymia influences brain activation during emotion perception but not regulation

Alexithymia is a psychological construct that can be divided into a cognitive and affective dimension. The cognitive dimension is characterized by difficulties in identifying, verbalizing and analysing feelings. The affective dimension comprises reduced levels of emotional experience and imagination. Alexithymia is widely regarded to arise from an impairment of emotion regulation. This is the first functional magnetic resonance imaging (fMRI) study to critically evaluate this by investigating the neural correlates of emotion regulation as a function of alexithymia levels. The aim of the current study was to investigate the neural correlates underlying the two alexithymia dimensions during emotion perception and emotion regulation. Using fMRI, we scanned 51 healthy subjects while viewing, reappraising or suppressing negative emotional pictures. The results support the idea that cognitive alexithymia, but not affective alexithymia, is associated with lower activation in emotional attention and recognition networks during emotion perception. However, in contrast with several theories, no alexithymia-related differences were found during emotion regulation (neither reappraisal nor suppression). These findings suggest that alexithymia may result from an early emotion processing deficit rather than compromised frontal circuits subserving higher-order emotion regulation processes.     

Sex differences in brain activation to emotional stimuli: a meta-analysis of neuroimaging studies

Substantial sex differences in emotional responses and perception have been reported in previous psychological and psychophysiological studies. For example, women have been found to respond more strongly to negative emotional stimuli, a sex difference that has been linked to an increased risk of depression and anxiety disorders. The extent to which such sex differences are reflected in corresponding differences in regional brain activation remains a largely unresolved issue, however, in part because relatively few neuroimaging studies have addressed this issue. Here, by conducting a quantitative meta-analysis of neuroimaging studies, we were able to substantially increase statistical power to detect sex differences relative to prior studies, by combining emotion studies which explicitly examined sex differences with the much larger number of studies that examined only women or men. We used an activation likelihood estimation approach to characterize sex differences in the likelihood of regional brain activation elicited by emotional stimuli relative to non-emotional stimuli. We examined sex differences separately for negative and positive emotions, in addition to examining all emotions combined. Sex differences varied markedly between negative and positive emotion studies. The majority of sex differences favoring women were observed for negative emotion, whereas the majority of the sex differences favoring men were observed for positive emotion. This valence-specificity was particularly evident for the amygdala. For negative emotion, women exhibited greater activation than men in the left amygdala, as well as in other regions including the left thalamus, hypothalamus, mammillary bodies, left caudate, and medial prefrontal cortex. In contrast, for positive emotion, men exhibited greater activation than women in the left amygdala, as well as greater activation in other regions including the bilateral inferior frontal gyrus and right fusiform gyrus. These meta-analysis findings indicate that the amygdala, a key region for emotion processing, exhibits valence-dependent sex differences in activation to emotional stimuli. The greater left amygdala response to negative emotion for women accords with previous reports that women respond more strongly to negative emotional stimuli, as well as with hypothesized links between increased neurobiological reactivity to negative emotion and increased prevalence of depression and anxiety disorders in women. The finding of greater left amygdala activation for positive emotional stimuli in men suggests that greater amygdala responses reported previously for men for specific types of positive stimuli may also extend to positive stimuli more generally. In summary, this study extends efforts to characterize sex differences in brain activation during emotion processing by providing the largest and most comprehensive quantitative meta-analysis to date, and for the first time examining sex differences as a function of positive vs. negative emotional valence. The current findings highlight the importance of considering sex as a potential factor modulating emotional processing and its underlying neural mechanisms, and more broadly, the need to consider individual differences in understanding the neurobiology of emotion.     

Neural responses associated with positive and negative emotion processing in patients with left versus right temporal lobe epilepsy

Studies on emotion processing in patients with temporal lobe epilepsy have dealt mainly with the processing of negative emotions. To further understand the neural basis of emotional disorders in temporal lobe epilepsy, we studied patterns of brain activation induced by implicit processing of negative and positive emotions perceived through facial expressions and emotionally salient stimuli in candidates for surgical treatment of intractable epilepsy. Using functional MRI, we compared, in patients with mesial temporal lobe epilepsy and healthy subjects, the patterns of brain activation elicited by the implicit processing of fearful, sad, and happy faces and pleasant and unpleasant scenes. The results revealed different patterns of activation in patients with left and right mesial temporal lobe epilepsy, compared with healthy subjects, suggesting that the left and right mesial temporal regions are involved differently in emotion processing, which could be related to different contributions in emotional arousal.     

Recent developments in alexithymia theory and research.

OBJECTIVE: To review recent developments in alexithymia theory and research that are relevant to the field of psychosomatic medicine. METHOD: Articles were selected from the alexithymia literature published over the past decade that describe advances in the theoretical understanding of alexithymia or report empirical investigations of the relationships of the construct with emotion regulation and with somatic illness and disease. Empirical investigations of the neural correlates of alexithymia were reviewed also, as were studies that explore therapeutic attempts to modify alexithymic characteristics. RESULTS: The salient features of the alexithymia construct are now thought to reflect deficits in the cognitive processing and regulation of emotions. This is supported by studies showing that alexithymia is associated with maladaptive styles of emotion regulation, low emotional intelligence, a bidirectional interhemispheric transfer deficit, and reduced rapid eye movement (REM) density (number of eye movements divided by number of REM periods). Although empirical evidence demonstrates that alexithymia is associated with several somatic disorders, more prospective studies are required to establish the direction of causality. Preliminary data suggest that psychotherapies involving specific techniques to enhance emotional awareness and integrate symbolic and subsymbolic elements of emotion schemas may be effective in reducing alexithymic characteristics. CONCLUSION: Alexithymia is proving to be a heuristically useful construct for exploring the role of personality and emotions in the pathogenesis of certain somatic illnesses and diseases.     

Neural correlates of processing emotional prosody in unipolar depression

Major depressive disorder (MDD) is characterized by a biased emotion perception. In the auditory domain, MDD patients have been shown to exhibit attenuated processing of positive emotions expressed by speech melody (prosody). So far, no neuroimaging studies examining the neural basis of altered processing of emotional prosody in MDD are available. In this study, we addressed this issue by examining the emotion bias in MDD during evaluation of happy, neutral, and angry prosodic stimuli on a five‐point Likert scale during functional magnetic resonance imaging (fMRI). As expected, MDD patients rated happy prosody less intense than healthy controls (HC). At neural level, stronger activation in the middle superior temporal gyrus (STG) and the amygdala was found in all participants when processing emotional as compared to neutral prosody. MDD patients exhibited an increased activation of the amygdala during processing prosody irrespective of valence while no significant differences between groups were found for the STG, indicating that altered processing of prosodic emotions in MDD occurs rather within the amygdala than in auditory areas. Concurring with the valence‐specific behavioral effect of attenuated evaluation of positive prosodic stimuli, activation within the left amygdala of MDD patients correlated with ratings of happy, but not neutral or angry prosody. Our study provides first insights in the neural basis of reduced experience of positive information and an abnormally increased amygdala activity during prosody processing.     

Neural activities associated with emotion recognition observed in men and women

Previous studies have suggested that men and women process emotional stimuli differently. In this study, we examined if there would be any consistency in regions of activation in men and women when processing stimuli portraying happy or sad emotions presented in the form of facial expressions, scenes, and words. A blocked design BOLD functional magnetic resonance imaging paradigm was employed to monitor the neural activities of male and female healthy volunteers while they were presented with the experimental stimuli. The imaging data revealed that the right insula and left thalamus were consistently activated for men, but not women, during emotion recognition of all forms of stimuli studied. To further understand the imaging data acquired, we conducted the protocol analysis method to identify the cognitive processes engaged while the men and women were viewing the emotional stimuli and deciding whether they were happy or sad. The findings suggest that men rely on the recall of past emotional experiences to evaluate current emotional experiences. This may explain why the insula, a structure important for self-induced or internally generated recalled emotions, was consistently activated in men while processing emotional stimuli. Our findings suggest possible gender-related neural responses to emotional stimuli.     

Blunted feelings: Alexithymia is associated with a diminished neural response to speech prosody

How we perceive emotional signals from our environment depends on our personality. Alexithymia, a personality trait characterized by difficulties in emotion regulation has been linked to aberrant brain activity for visual emotional processing. Whether alexithymia also affects the brain’s perception of emotional speech prosody is currently unknown. We used functional magnetic resonance imaging to investigate the impact of alexithymia on hemodynamic activity of three a priori regions of the prosody network: the superior temporal gyrus (STG), the inferior frontal gyrus and the amygdala. Twenty-two subjects performed an explicit task (emotional prosody categorization) and an implicit task (metrical stress evaluation) on the same prosodic stimuli. Irrespective of task, alexithymia was associated with a blunted response of the right STG and the bilateral amygdalae to angry, surprised and neutral prosody. Individuals with difficulty describing feelings deactivated the left STG and the bilateral amygdalae to a lesser extent in response to angry compared with neutral prosody, suggesting that they perceived angry prosody as relatively more salient than neutral prosody. In conclusion, alexithymia may be associated with a generally blunted neural response to speech prosody. Such restricted prosodic processing may contribute to problems in social communication associated with this personality trait.     

Effect of impaired recognition and expression of emotions on frontocingulate cortices: an fMRI study of men with alexithymia

OBJECTIVE: Although the brain areas involved in emotional response and in the recognition of others' emotions have been reported, the neural bases of individual differences in affective style remain to be elucidated. Alexithymia, i.e., impairment of the ability to identify and communicate one's emotional state, influences how emotions are regulated. Alexithymia has been hypothesized to involve anterior cingulate dysfunction. Therefore, the authors searched for differential cerebral regional activation in response to emotional stimuli in subjects with alexithymia. METHOD: Two groups of eight men each were selected from 437 healthy subjects on the basis of high or low scores on the 20-item Toronto Alexithymia Scale. Using functional magnetic resonance imaging (fMRI), the authors compared the two groups for their regional cerebral activation in response to the presentation of pictures with validated positive or negative arousal capabilities. RESULTS: Men with alexithymia demonstrated less cerebral activation in the left mediofrontal-paracingulate cortex in response to highly negative stimuli and more activation in the anterior cingulate, mediofrontal cortex, and middle frontal gyrus in response to highly positive stimuli than men without alexithymia. CONCLUSIONS: These findings provide direct evidence that alexithymia, a personality trait playing a role in affect regulation, is linked with differences in anterior cingulate and mediofrontal activity during emotional stimuli processing.     

How emotional abilities modulate the influence of early life stress on hippocampal functioning

Early life stress (ELS) is known to have considerable influence on brain development, mental health and affective functioning. Previous investigations have shown that alexithymia, a prevalent personality trait associated with difficulties experiencing and verbalizing emotions, is particularly related to ELS. The aim of the present study was to investigate how neural correlates of emotional experiences in alexithymia are altered in the presence and absence of ELS. Therefore, 50 healthy individuals with different levels of alexithymia were matched regarding ELS and investigated with respect to neural correlates of audio-visually induced emotional experiences via functional magnetic resonance imaging. The main finding was that ELS modulated hippocampal responses to pleasant (>neutral) stimuli in high-alexithymic individuals, whereas there was no such modulation in low-alexithymic individuals matched for ELS. Behavioral and psychophysiological results followed a similar pattern. When considered independent of ELS, alexithymia was associated with decreased responses in insula (pleasant > neutral) and temporal pole (unpleasant > neutral). Our results show that the influence of ELS on emotional brain responses seems to be modulated by an individual’s degree of alexithymia. Potentially, protective and adverse effects of emotional abilities on brain responses to emotional experiences are discussed.     

Modulating the processing of emotional stimuli by cognitive demand

Emotional processing is influenced by cognitive processes and vice versa, indicating a profound interaction of these domains. The investigation of the neural mechanisms underlying this interaction is not only highly relevant for understanding the organization of human brain function. Rather, it may also help in understanding dysregulated emotions in affective disorders and in elucidating the neurobiology of cognitive behavioural therapy (e.g. in borderline personality disorder), which aims at modulating dysfunctional emotion processes by cognitive techniques, such as restructuring. In the majority of earlier studies investigating the interaction of emotions and cognition, the main focus has been on the investigation of the effects of emotional stimuli or, more general, emotional processing, e.g. instituted by emotional material that needed to be processed, on cognitive performance and neural activation patterns. Here we pursued the opposite approach and investigated the modulation of implicit processing of emotional stimuli by cognitive demands using an event-related functional magnetic resonance imaging--study on a motor short-term memory paradigm with emotional interferences. Subjects were visually presented a finger-sequence consisting either of four (easy condition) or six (difficult condition) items, which they had to memorize. After a short pause positive, negative or neutral International affective picture system pictures or a green dot (as control condition) were presented. Subjects were instructed to reproduce the memorized sequence manually as soon as the picture disappeared. Analysis showed that with increasing cognitive demand (long relative to short sequences), neural responses to emotional pictures were significantly reduced in amygdala and orbitofrontal cortex. In contrast, the more difficult task evoked stronger activation in a widespread frontoparietal network. As stimuli were task-relevant go-cues and hence had to be processed perceptually, we would interpret this as a specific attenuation of affective responses by concurrent cognitive processing--potentially reflecting a relocation of resources mediated by the frontoparietal network.     

Brain activation during the perception of stressful word stimuli concerning interpersonal relationships in anorexia nervosa patients with high degrees of alexithymia in an fMRI paradigm

Several studies have reported that anorexia nervosa (AN) patients have high levels of alexithymia. However, relatively little is known about the underlying neurobiological relationships between alexithymia and AN. We used functional magnetic resonance imaging to examine the brain responses in 30 AN patients and 20 healthy women during the processing of negative words concerning interpersonal relationships. We investigated the relationship between alexithymia levels and brain activation in AN. AN patients showed significant activation of the orbitofrontal cortex, dorsolateral prefrontal cortex and medial prefrontal cortex while processing negative words concerning interpersonal relationships, as compared to the processing of neutral words. Moreover, the subjective rating of unpleasantness with negative words and neural activities in the amygdala, posterior cingulate cortex (PCC) and anterior cingulate cortex (ACC) negatively correlated with the level of alexithymia in AN. Our neuroimaging results suggest that AN patients tend to cognitively process negative words concerning interpersonal relationships, resulting in activation of the prefrontal cortex. Lower activation of the amygdala, PCC and ACC in response to these words may contribute to the impairments of emotional processing that are hallmarks of alexithymia. Functional abnormalities associated with alexithymia may be involved in the emotional processing impairments in AN patients.     

Imaging the up’s and down’s of emotion regulation in lifetime depression

Reappraisal is a particularly effective strategy for influencing emotional experiences, specifically for reducing the impact of negative stimuli. Although depression has repeatedly been linked to dysfunctional behavioral and neural emotion regulation, prefrontal and amygdala engagement seems to vary with clinical characteristics and the specific regulation strategy used. Whereas previous neuroimaging research has focused on down-regulating reactions to emotionally evocative scenes, the current study compared up- and down-regulation in response to angry facial expressions in patients with depression and healthy individuals. During the initial viewing of faces, patients with depression showed hypoactivation particularly in areas implicated in emotion generation, i.e., amygdala, insula and putamen. In contrast, up-regulating negative emotions yielded stronger recruitment of core face processing areas and posterior medial frontal cortex in patients than in controls. However, group differences did not extend to resting-state functional connectivity. Recurrent depression was inversely associated with amygdala activation specifically during down-regulation, but differences in medication status may limit the current findings. Despite a pattern of reduced neural emotional reactivity in mainly medicated patients, their ‘successful’ recruitment of the regulation network for up-regulation might point toward an effective use of reappraisal when increasing negative emotions. Future studies need to address how patients might benefit from transferring this ability to adaptive goals, such as improving interpersonal emotion regulation.     

Emotion regulation in spider phobia: role of the medial prefrontal cortex

Phobic responses are strong emotional reactions towards phobic objects, which can be described as a deficit in the automatic regulation of emotions. Difficulties in the voluntary cognitive control of these emotions suggest a further phobia-specific deficit in effortful emotion regulation mechanisms. The actual study is based on this emotion regulation conceptualization of specific phobias. The aim is to investigate the neural correlates of these two emotion regulation deficits in spider phobics. Sixteen spider phobic females participated in a functional magnetic resonance imaging (fMRI) study in which they were asked to voluntarily up- and down-regulate their emotions elicited by spider and generally aversive pictures with a reappraisal strategy. In line with the hypothesis concerning an automatic emotion regulation deficit, increased activity in the insula and reduced activity in the ventromedial prefrontal cortex was observed. Furthermore, phobia-specific effortful regulation within phobics was associated with altered activity in medial prefrontal cortex areas. Altogether, these results suggest that spider phobic subjects are indeed characterized by a deficit in the automatic as well as the effortful regulation of emotions elicited by phobic compared with aversive stimuli. These two forms of phobic emotion regulation deficits are associated with altered activity in different medial prefrontal cortex subregions.     

Amygdala activation at 3T in response to human and avatar facial expressions of emotions

Facial expressions of emotions are important in nonverbal communication. Although numerous neural structures have been identified to be involved in emotional face processing, the amygdala is thought to be a core moderator. While previous studies have relied on facial images of humans, the present study is concerned with the effect of computer-generated (avatar) emotional faces on amygdala activation. Moreover, elicited activation patterns in response to viewing avatar faces are compared with the neuronal responses to human facial expressions of emotions. Twelve healthy subjects (five females) performed facial emotion recognition tasks with optimized 3T event-related fMRI. Robust amygdala activation was apparent in response to both human and avatar emotional faces, but the response was significantly stronger to human faces in face-sensitive structures, i.e. fusiform gyri. We suggest that avatars could be a useful tool in neuroimaging studies of facial expression processing because they elicit amygdala activation similarly to human faces, yet have the advantage of being highly manipulable and fully controllable. However, the finding of differences between human and avatar faces in face-sensitive regions indicates the presence of mechanisms by which human brains can differentiate between them. This mechanism merits further investigation.     

Influence of Emotional Processing on Working Memory in Schizophrenia

Research on emotional processing in schizophrenia suggests relatively intact subjective responses to affective stimuli “in the moment.” However, neuroimaging evidence suggests diminished activation in brain regions associated with emotional processing in schizophrenia. We asked whether given a more vulnerable cognitive system in schizophrenia, individuals with this disorder would show increased or decreased modulation of working memory (WM) as a function of the emotional content of stimuli compared with healthy control subjects. In addition, we examined whether higher anhedonia levels were associated with a diminished impact of emotion on behavioral and brain activation responses. In the present study, 38 individuals with schizophrenia and 32 healthy individuals completed blocks of a 2-back WM task in a functional magnetic resonance imaging scanning session. Blocks contained faces displaying either only neutral stimuli or neutral and emotional stimuli (happy or fearful faces), randomly intermixed and occurring both as targets and non-targets. Both groups showed higher accuracy but slower reaction time for negative compared to neutral stimuli. Individuals with schizophrenia showed intact amygdala activity in response to emotionally evocative stimuli, but demonstrated altered dorsolateral prefrontal cortex (DLPFC) and hippocampal activity while performing an emotionally loaded WM-task. Higher levels of social anhedonia were associated with diminished amygdala responses to emotional stimuli and increased DLPFC activity in individuals with schizophrenia. Emotional arousal may challenge dorsal-frontal control systems, which may have both beneficial and detrimental influences. Our findings suggest that disturbances in emotional processing in schizophrenia relate to alterations in emotion-cognition interactions rather than to the perception and subjective experience of emotion per se.     

Neural long-term effects of emotion regulation on episodic memory processes

Emotions can enhance memory which is on the one hand advantageous, but on the other hand may be detrimental in the long term, for example in the case of traumatic events. Although cognitive emotion regulation may reduce emotion experience and corresponding neural activation, at present little is known about its influence on long-term memory. We investigated memory for emotional pictures in healthy female subjects 1 year after voluntary emotion regulation using fMRI. Whereas memory performance was not affected by regulation, our data revealed a dissociation of brain regions involved in memory encoding and recognition depending on whether emotional engagement during encoding had been downregulated. Emotional engagement during encoding resulted in a long-term subsequent memory effect in mesolimbic brain regions and hippocampus, and in recognition-related activation in the amygdala. In contrast, when negative emotions had been downregulated during encoding memory performance was predicted by prefrontal activation. Our data suggest that memory for emotionally encoded stimuli is supported by emotional re-activation, whereas memory for successfully encoded items during emotion regulation is rather supported by recognition of features and cognitive contents. These results contribute to research on long-term effects of emotion regulation in everyday life and open new avenues to understand and possibly influence traumatic memory traces.     

Behavioral and brain oscillatory correlates of affective processing in subclinical depression

Named among the most dangerous diseases of the modern era, depression is characterized primarily by distortions in the affective sphere. Despite extensive investigations of underlying the neural background, mechanisms of the distortion still remain unknown. The current study analyzed brain oscillatory dynamics in different frequencies during resting state and presentation of affective stimuli in nonclinical individuals with high Beck Depression Inventory–II (BDI–II) scores (HB) versus controls. Both behavioral and electrocortical “markers” of clinical depression were apparent at subclinical level. A resting-state electroencephalogram (EEG) of HB revealed increased power in low frequencies, predominantly in the frontal cortical areas, that is in accordance with a “spatio-temporal dysfunction” model of depression. Related to that, transition from an eyes-closed to eyes-open condition was associated with diminished alpha blockade in HB, suggesting difficulties with the relocation of attention focus from inner processes toward environmental stimuli. Subsequently, independently of a sign of emotion, five out of six discrete emotions were evaluated as less valenced and four out of six as less intense by HB than by controls, corroborating the view of emotion context insensitivity (ECI) associated with depression. Underlying brain oscillatory dynamics revealed that depression was associated with deficits in the early, implicit, processing stages of emotional stimuli. Later processing stages were characterized by prominent power surges in low and alpha frequencies, presumably indicating emotion upregulation processes and increased engagement of cognitive mechanisms in affective tasks. The study provides brain oscillatory-based mechanisms of emotion processing distortions associated with depression.     

Mixed emotions: the contribution of alexithymia to the emotional symptoms of autism

It is widely accepted that autism is associated with disordered emotion processing and, in particular, with deficits of emotional reciprocity such as impaired emotion recognition and reduced empathy. However, a close examination of the literature reveals wide heterogeneity within the autistic population with respect to emotional competence. Here we argue that, where observed, emotional impairments are due to alexithymia—a condition that frequently co-occurs with autism—rather than a feature of autism per se. Alexithymia is a condition characterized by a reduced ability to identify and describe one''s own emotion, but which results in reduced empathy and an impaired ability to recognize the emotions of others. We briefly review studies of emotion processing in alexithymia, and in autism, before describing a recent series of studies directly testing this ‘alexithymia hypothesis''. If found to be correct, the alexithymia hypothesis has wide-reaching implications for the study of autism, and how we might best support subgroups of autistic individuals with, and without, accompanying alexithymia. Finally, we note the presence of elevated rates of alexithymia, and inconsistent reports of emotional impairments, in eating disorders, schizophrenia, substance abuse, Parkinson''s Disease, multiple sclerosis and anxiety disorders. We speculate that examining the contribution of alexithymia to the emotional symptoms of these disorders may bear fruit in the same way that it is starting to do in autism.     

Mechanistic Comparisons of Functional Domains across Pediatric and Adult Bipolar Disorder Highlight Similarities, As Well As Differences, Influenced by the Developing Brain

Recent neuroimaging studies have uncovered much about the specific neural deficits in adult bipolar disorder (ABD), but despite promising results, neuroimaging research for pediatric bipolar disorder (PBD) is still developing. The neuroimaging literature is highly heterogeneous, varying in the paradigms used and in participants' mood states and medication status. Despite this variability, several dominant patterns emerge. In response to emotional stimuli, both ABD and PBD show limbic hyperactivity coupled with hypoactivity in ventral prefrontal emotion regulation systems. This pattern occurred most robustly in response to negative incidental stimuli and was especially apparent in manic PBD. ABD showed more variability in ventral prefrontal activity, possibly due to maturational and medication factors. On numerous cognitive paradigms, PBD showed dorsal prefrontal hypoactivity linked to ventral dysfunction, whereas ABD showed compensatory frontal, parietal, and temporal activity with paradigm-specific variations. In emotion-cognition interaction paradigms, patients show dysregulation in regions interfacing between cognitive and emotional brain systems (e.g., ventral prefrontal and cingulate cortices), which expend extra effort to process emotional stimuli effectively and recruit additional posterior attention systems to cope with affective instability. In addition, novel functional connectivity techniques have uncovered connectivity deficits between frontal and limbic regions in ABD and PBD at rest and during active emotional and cognitive tasks. Finally, the neuroimaging literature currently lacks cross-sectional studies comparing PBD with ABD and longitudinal studies following children and adolescents with BD into adulthood. Such studies would provide important insights into patients' prognosis and would determine targets for early interventions in the evolving illness diathesis.     

Neural systems for executive and emotional processing are modulated by symptoms of posttraumatic stress disorder in Iraq War veterans

The symptom-provocation paradigms generally used in neuroimaging studies of posttraumatic stress disorder (PTSD) have placed high demands on emotion processing but lacked cognitive processing, thereby limiting the ability to assess alterations in neural systems that subserve executive functions and their interactions with emotion processing. Thirty-nine veterans from Iraq and Afghanistan underwent functional magnetic resonance imaging while exposed to emotional combat-related and neutral civilian scenes interleaved with an executive processing task. Contrast activation maps were regressed against PTSD symptoms as measured by the Davidson Trauma Scale. Activation for emotional compared with neutral stimuli was highly positively correlated with level of PTSD symptoms in ventral frontolimbic regions, notably the ventromedial prefrontal cortex, inferior frontal gyrus, and ventral anterior cingulate gyrus. Conversely, activation for the executive task was negatively correlated with PTSD symptoms in the dorsal executive network, notably the middle frontal gyrus, dorsal anterior cingulate gyrus, and inferior parietal lobule. Thus, there is a strong link between the subjectively assessed behavioral phenomenology of PTSD and objective neurobiological markers. These findings extend the largely symptom provocation-based functional neuroanatomy to provide evidence that interrelated executive and emotional processing systems of the brain are differentially affected by PTSD symptomatology in recently deployed war veterans.