Left and right amygdala - mediofrontal cortical functional connectivity is differentially modulated by harm avoidance

Imaging of the brain-heart axis: prognostic value in a European setting

BACKGROUND AND AIMS

Increasing data suggest that stress-related neural activity (SNA) is associated with subsequent major adverse cardiovascular events (MACE) and may represent a therapeutic target. Current evidence is exclusively based on populations from the U.S. and Asia where limited information about cardiovascular disease risk was available. This study sought to investigate whether SNA imaging has clinical value in a well-characterized cohort of cardiovascular patients in Europe.

METHODS

In this single-centre study, a total of 963 patients (mean age 58.4 ± 16.1 years, 40.7% female) with known cardiovascular status, ranging from 'at-risk' to manifest disease, and without active cancer underwent 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography between 1 January 2005 and 31 August 2019. Stress-related neural activity was assessed with validated methods and relations between SNA and MACE (non-fatal stroke, non-fatal myocardial infarction, coronary revascularization, and cardiovascular death) or all-cause mortality by time-to-event analysis.

RESULTS

Over a maximum follow-up of 17 years, 118 individuals (12.3%) experienced MACE, and 270 (28.0%) died. In univariate analyses, SNA significantly correlated with an increased risk of MACE (sub-distribution hazard ratio 1.52, 95% CI 1.05-2.19; P = .026) or death (hazard ratio 2.49, 95% CI 1.96-3.17; P < .001). In multivariable analyses, the association between SNA imaging and MACE was lost when details of the cardiovascular status were added to the models. Conversely, the relationship between SNA imaging and all-cause mortality persisted after multivariable adjustments.

CONCLUSIONS

In a European patient cohort where cardiovascular status is known, SNA imaging is a robust and independent predictor of all-cause mortality, but its prognostic value for MACE is less evident. Further studies should define specific patient populations that might profit from SNA imaging.

Partial Klüver-Bucy syndrome in a Paediatric patient: A post-neurosurgical and neuropsychological cases

A variety of cognitive, behavioural, and emotional impairments have been reported in the literature that are associated with the resection of the temporal cortex. Klüver-Bucy syndrome is one infrequently reported disorder in the paediatric population. This paper describes the neuropsychological findings of a female paediatric patient at 7 and 10 years of age with a diagnosis of partial Klüver-Bucy syndrome (pKBS) following total resection of the amygdala and right hippocampus to resect a glioma. The patient presented emotional problems, aggressiveness, hypermetamorphosis, social indifference, and behavioural dysexecutive syndrome, which was found at both 7 and 10 years, but with a decrease in the severity of alterations in attention, impulsivity, hyperactivity, and aggressive behaviour in a second evaluation after she had a neuropsychological intervention. These findings describe the neuropsychological profile of paediatric case with resection of the amygdala and right temporal lobe.

Lateralization of the 5-HT1A receptors in the basolateral amygdala in metabolic and anxiety responses to chronic restraint stress

Behavioral and functional studies describe hemispheric asymmetry in anxiety and metabolic behaviors in responses to stress. However, no study has reported serotonergic receptor (the 5-HT1A receptor) lateralization in the basolateral amygdala (BLA) in vivo on anxiety and metabolic behaviors under stress. In the present study, the effect of unilateral and bilateral suppression of the 5-HT1A receptor in the BLA on anxiety, and metabolic responses to chronic restraint stress was assessed. Male Wistar rats 7 days after cannulation into the BLA received chronic restraint stress for 14 consecutive days. 20 minutes before induction of stress, WAY-100-635 (selective 5-HT1A antagonist) or sterile saline (vehicle) was administered either uni- or bi-laterally into the BLA. Behavioral (elevated plus maze; EPM, and open field test), and metabolic parameter studies were performed. Results showed that stress causes a significant increase in weight gain compared to control. In the non-stress condition, the left and bilaterally, and in the stress condition the right, left, and both sides, inhibition of 5-HT1A in the BLA reduced weight gain. In the restraint stress condition, only inhibition of the 5-HT1A receptor in the left BLA led to decreased food intake compared to the control group. In stress conditions, inhibition of the 5-HT1A receptor on the right, left, and bilateral BLA increased water intake compared to the stress group. Inhibition of the 5-HT1A receptor on the left side of the BLA by WAY-100-635 induced anxiety-like behaviors in stressed rats. Similarly, WAY-100-635 on the left BLA effectively caused anxiety-like behaviors in both EPM and open field tests in the control animals. In conclusion, it seems that 5-HT1A receptors in the left BLA are more responsible for anxiety-like behaviors and metabolic changes in responses to stress.

Temperament & Character account for brain functional connectivity at rest: A diathesis-stress model of functional dysregulation in psychosis

The human brain's resting-state functional connectivity (rsFC) provides stable trait-like measures of differences in the perceptual, cognitive, emotional, and social functioning of individuals. The rsFC of the prefrontal cortex is hypothesized to mediate a person's rational self-government, as is also measured by personality, so we tested whether its connectivity networks account for vulnerability to psychosis and related personality configurations. Young adults were recruited as outpatients or controls from the same communities around psychiatric clinics. Healthy controls (n = 30) and clinically stable outpatients with bipolar disorder (n = 35) or schizophrenia (n = 27) were diagnosed by structured interviews, and then were assessed with standardized protocols of the Human Connectome Project. Data-driven clustering identified five groups of patients with distinct patterns of rsFC regardless of diagnosis. These groups were distinguished by rsFC networks that regulate specific biopsychosocial aspects of psychosis: sensory hypersensitivity, negative emotional balance, impaired attentional control, avolition, and social mistrust. The rsFc group differences were validated by independent measures of white matter microstructure, personality, and clinical features not used to identify the subjects. We confirmed that each connectivity group was organized by differential collaborative interactions among six prefrontal and eight other automatically-coactivated networks. The temperament and character traits of the members of these groups strongly accounted for the differences in rsFC between groups, indicating that configurations of rsFC are internal representations of personality organization. These representations involve weakly self-regulated emotional drives of fear, irrational desire, and mistrust, which predispose to psychopathology. However, stable outpatients with different diagnoses (bipolar or schizophrenic psychoses) were highly similar in rsFC and personality. This supports a diathesis-stress model in which different complex adaptive systems regulate predisposition (which is similar in stable outpatients despite diagnosis) and stress-induced clinical dysfunction (which differs by diagnosis).

Antidepressant-induced mania in panic disorder: a single-case study of clinical and functional connectivity characteristics

Background

Mental health issues, including panic disorder (PD), are prevalent and often co-occur with anxiety and bipolar disorders. While panic disorder is characterized by unexpected panic attacks, and its treatment often involves antidepressants, there is a 20-40% risk of inducing mania (antidepressant-induced mania) during treatment, making it crucial to understand mania risk factors. However, research on clinical and neurological characteristics of patients with anxiety disorders who develop mania is limited.

Methods

In this single case study, we conducted a larger prospective study on panic disorder, comparing baseline data between one patient who developed mania (PD-manic) and others who did not (PD-NM group). We enrolled 27 patients with panic disorder and 30 healthy controls (HCs) and examined alterations in amygdala-based brain connectivity using a seed-based whole-brain approach. We also performed exploratory comparisons with healthy controls using ROI-to-ROI analyses and conducted statistical inferences at a threshold of cluster-level family-wise error-corrected p < 0.05, with the cluster-forming threshold at the voxel level of uncorrected p < 0.001.

Results

The patient with PD-mania showed lower connectivity in brain regions related to the default mode network (left precuneous cortex, maximum z-value within the cluster = -6.99) and frontoparietal network (right middle frontal gyrus, maximum z-value within the cluster = -7.38; two regions in left supramarginal gyrus, maximum z-value within the cluster = -5.02 and -5.86), and higher in brain regions associated with visual processing network (right lingual gyrus, maximum z-value within the cluster = 7.86; right lateral occipital cortex, maximum z-value within the cluster = 8.09; right medial temporal gyrus, maximum z-value within the cluster = 8.16) in the patient with PD-mania compared to the PD-NM group. One significantly identified cluster, the left medial temporal gyrus (maximum z-value within the cluster = 5.82), presented higher resting-state functional connectivity with the right amygdala. Additionally, ROI-to-ROI analysis revealed that significant clusters between PD-manic and PD-NM groups differed from HCs in the PD-manic group but not in the PD-NM group.

Conclusion

Here, we demonstrate altered amygdala-DMN and amygdala-FPN connectivity in the PD-manic patient, as reported in bipolar disorder (hypo) manic episodes. Our study suggests that amygdala-based resting-state functional connectivity could serve as a potential biomarker for antidepressant-induced mania in panic disorder patients. Our findings provide an advance in understanding the neurological basis of antidepressant-induced mania, but further research with larger cohorts and more cases is necessary for a broader perspective on this issue.

Amygdala hyperactivation relates to eating behaviour: a potential indicator of food addiction in Prader-Willi syndrome

Prader-Willi syndrome is a rare neurodevelopmental genetic disorder characterized by various endocrine, cognitive and behavioural problems. The symptoms include an obsession for food and reduced satiety, which leads to hyperphagia and morbid obesity. Neuropsychological studies have reported that Prader-Willi patients display altered social interactions with a specific weakness in interpreting social information and responding to them, a symptom close to that observed in autism spectrum disorders. In the present case-control study, we hypothesized that brain regions associated with compulsive eating behaviour would be abnormally activated by food-related odours in Prader-Willi syndrome, as these can stimulate the appetite and induce hunger-related behaviour. We conducted a brain imaging study using the olfactory modality because odours have a high-hedonic valence and can cause stronger emotional reactions than other modalities. Further, the olfactory system is also intimately associated with the endocrine regulation of energy balance and is the most appropriate modality for studies of Prader-Willi syndrome. A total of 16 Prader-Willi participants were recruited for this study, which is a significant achievement given the low incidence rate of this rare disease. The second group of 11 control age-matched subjects also participated in the brain imaging study. In the MRI scanner, using an MRI-compatible olfactometer during 56 block sessions, we randomly presented two odours (tulip and caramel), which have different hedonic valence and a different capacity to arouse hunger-related behaviour. Our results demonstrate that Prader-Willi participants have abnormal activity in the brain reward system that regulates eating behaviour. Indeed, we found that these patients had right amygdala activity up to five times higher in response to a food odour (caramel) compared with the tulip odour. In contrast, age-matched control participants had similar activity levels in response to both odours. The amygdala activity levels were found to be associated with the severity of the hyperphagia in Prader-Willi patients. Our results provide evidence for functional alteration of the right amygdala in Prader-Willi syndrome, which is part of the brain network involved in food addiction modulated by the ghrelin and oxytocin systems, which may drive the hyperphagia. Our study provides important new insights into the functioning of emotion-related brain circuits and pathology, and it is one of the few to explore the dysfunction of the neural circuits involved in emotion and addiction in Prader-Willi syndrome. It suggests new directions for the exploration and remediation of addictive behaviours.

Changing role of the amygdala in affective and cognitive traits between early and late adulthood

Introduction

Healthy aging is typically associated with cognitive decline and lower negative affect. Previous studies have reported a significant and opposite role of the amygdala in relation to cognitive and affective processing in early adulthood. However, it remains unclear how aging impacts such relationships.

Methods

Seventy-seven healthy participants including 40 young (mean age = 26.1 years) and 37 older (mean age = 61.8 years) adults completed a functional MRI Affective Stroop (AS) paradigm, a cognitive battery, and the state-trait anxiety inventory. The AS fMRI paradigm included "task trials," where participants saw a positively, negatively or neutrally valenced distractor image, followed by a numerical display, followed by another distractor image. We extracted signal in both amygdalas during the AS Task and compared it across all conditions and age group. We further conducted moderation analyses to investigate the impact of aging on the relationship between amygdala activation and anxiety or cognitive variables, respectively.

Results

At the behavioral level, older participants showed lower trait anxiety than the younger adults (p = 0.002). While overall slower during the AS task, older adults achieved comparable accuracy during the AS task, relative to the younger adults. At the brain level, we revealed a significant interaction between age group and trial types in amygdala activation (F = 4.9, p = 0.03), with the older group showing stronger activation during the most complex trials compared to the passive view trials. We further found that age significantly modulated the relationship between anxiety and the left amygdala activation during negative stimuli, where the younger adults showed a positive association while the older adults showed a negative association. Age also significantly modulated the relationship between verbal fluency and left amygdala activation during incongruent versus view trials, with the younger adults showing a negative association and the older adults showing a positive association.

Discussion

The current study suggests that the role of the amygdala on both emotional processing and cognitive traits changes between early and late adulthood.

Associations between anxiety, centromedial amygdala volume, and complex verbal fluency in middle-aged to older adults

Symptoms of anxiety are related to decreases in cognitive performance in middle-aged to older adults (i.e., ages 50 and older; MOA). Verbal fluency (VF), assessed with the Delis-Kaplan Executive Function System (D-KEFS) Category Switching (VF-CS) task, captures elements of executive function such as semantic memory, response initiation and inhibition, and cognitive flexibility. The present study examined the link between anxiety symptoms and VF-CS to better understand how this association affects such executive functions in MOA. We hypothesized that higher subclinical Beck Anxiety Inventory (BAI) scores would be associated with lower VF-CS. To further investigate the underlying neurobiological basis of an expected inverse relationship, total amygdala volume, centromedial amygdala (CMA) volume, and basolateral amygdala (BLA) volume were examined as they related to VF-CS scores on the D-KEFS. Based on extant research on connectivity and functioning between the CMA and BLA, we hypothesized that larger BLA volumes would be associated with lower anxiety scores and exhibit positive relationships with VF-CS. A sample of 63 MOA were recruited from the Providence, Rhode Island area as a part of a parent study on cardiovascular diseases. Participants completed self-report measures about physical and emotional health, a neuropsychological assessment, and a magnetic resonance imaging scan (MRI). Multiple hierarchical regressions were performed to examine relationships between variables of interest. Contrary to hypotheses, no significant relationship emerged between VF-CS and BAI scores, and BLA volume was not associated with either BAI scores or VF-CS. However, a significant positive relationship was observed between CMA volume and VF-CS. The significant relationship found between CMA and VF-CS may reflect the upward slope of the quadratic relationship between arousal and cognitive performance on the Yerkes-Dodson curve. These findings newly implicate CMA volume specifically as a possible neuromarker linking emotional arousal and cognitive performance in MOA.

The neurobiology of obsessive-compulsive personality disorder: a systematic review

BACKGROUND

A number of recent investigations have focused on the neurobiology of obsessive-compulsive personality disorder (OCPD). However, there have been few reviews of this literature with no detailed model proposed. We therefore undertook a systematic review of these investigations, aiming to map the available evidence and investigate whether it is possible to formulate a detailed model of the neurobiology of OCPD.

METHODS

OCPD can be considered from both categorical and dimensional perspectives. An electronic search was therefore conducted using terms that would address not only OCPD as a category, but also related constructs, such as perfectionism, that would capture research on neuropsychology, neuroimaging, neurochemistry, and neurogenetics.

RESULTS

A total of 1059 articles were retrieved, with 87 ultimately selected for abstract screening, resulting in a final selection of 49 articles focusing on neurobiological investigations relevant to OCPD. Impaired executive function and cognitive inflexibility are common neuropsychological traits in this condition, and suggest that obsessive-compulsive disorder (OCD) and OCPD may lie on a continuum. However, neuroimaging studies in OCPD indicate the involvement of specific neurocircuitry, including the precuneus and amygdala, and so suggest that OCD and OCPD may have important differences. Although OCPD has a heritable component, we found no well-powered genetic studies of OCPD.

CONCLUSION

Although knowledge in this area has advanced, there are insufficient data on which to base a comprehensive model of the neurobiology of OCPD. Given the clinical importance of OCPD, further work to understand the mechanisms that underpin this condition is warranted.

The antidepressant effect of cognitive reappraisal training on individuals cognitively vulnerable to depression: Could cognitive bias be modified through the prefrontal–amygdala circuits?

Cognitive reappraisal (CR) is one of the core treatment components of cognitive behavioral therapy (CBT) and is the gold standard treatment for major depressive disorders. Accumulating evidence indicates that cognitive reappraisal could function as a protective factor of cognitive vulnerability to depression. However, the neural mechanism by which CR training reduces cognitive vulnerability to depression is unclear. There is ample evidence that the prefrontal–amygdala circuit is involved in CR. This study proposes a novel cognitive bias model of CR training which hypothesizes that CR training may improve the generation ability of CR with altered prefrontal–amygdala functional activation/connectivity, thus reducing negative cognitive bias (negative attention bias, negative memory bias, negative interpretation bias, and/or negative rumination bias) and alleviating depressive symptoms. This study aims to (1) explore whether there is abnormal CR strategy generation ability in individuals who are cognitively vulnerable to depression; (2) test the hypothesis that CR training alleviates depressive symptoms through the mediators of cognitive bias (interpretation bias and/or rumination bias); (3) explore the neural mechanism by which CR training may enhance the ability of CR strategy generation; and (4) examine the short- and long-term effects of CR training on the reduction in depressive symptoms in individuals who are cognitively vulnerable to depression following intervention and 6 months later. The study is promising, providing theoretical and practical evidence for the early intervention of depression-vulnerable individuals.

The neurobiology of misophonia and implications for novel, neuroscience-driven interventions

Decreased tolerance in response to specific every-day sounds (misophonia) is a serious, debilitating disorder that is gaining rapid recognition within the mental health community. Emerging research findings suggest that misophonia may have a unique neural signature. Specifically, when examining responses to misophonic trigger sounds, differences emerge at a physiological and neural level from potentially overlapping psychopathologies. While these findings are preliminary and in need of replication, they support the hypothesis that misophonia is a unique disorder. In this theoretical paper, we begin by reviewing the candidate networks that may be at play in this complex disorder (e.g., regulatory, sensory, and auditory). We then summarize current neuroimaging findings in misophonia and present areas of overlap and divergence from other mental health disorders that are hypothesized to co-occur with misophonia (e.g., obsessive compulsive disorder). Future studies needed to further our understanding of the neuroscience of misophonia will also be discussed. Next, we introduce the potential of neurostimulation as a tool to treat neural dysfunction in misophonia. We describe how neurostimulation research has led to novel interventions in psychiatric disorders, targeting regions that may also be relevant to misophonia. The paper is concluded by presenting several options for how neurostimulation interventions for misophonia could be crafted.

A pilot study exploring the effect of repetitive transcranial magnetic stimulation (rTMS) treatment on cerebral blood flow and its relation to clinical outcomes in severe enduring anorexia nervosa

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is a novel treatment option for people with severe enduring anorexia nervosa (SE-AN), but associated neurobiological changes are poorly understood. This study investigated the effect of rTMS treatment on regional cerebral blood flow (CBF) and whether any observed changes in CBF are associated with changes in clinical outcomes in people with SE-AN.

METHODS

As part of a randomised sham-controlled feasibility trial of 20 sessions of high-frequency rTMS to the left dorsolateral prefrontal cortex, 26 of 34 trial participants completed arterial spin labelling (ASL) functional magnetic resonance imaging (fMRI) to quantify regional and global resting state CBF before (pre-randomisation baseline) and after real or sham treatment (1-month post-randomisation). A group of healthy females (n = 30) were recruited for baseline comparison. Clinical outcomes, including BMI, and depression and anxiety symptoms, were assessed at baseline, 1-, 4-, and 18-months post-randomisation.

RESULTS

No group differences in regional CBF were identified between the SE-AN and healthy comparison participants. A significant treatment-by-time interaction in a medial temporal lobe cluster with the maximal peak in the right amygdala was identified, reflecting a greater reduction in amygdala CBF following real rTMS compared to sham. Participants with the greatest rTMS-related reduction in amygdala CBF (i.e., between baseline and 1-month post-randomisation) showed the greatest sustained weight gain at 18-months post-randomisation. Higher baseline CBF in the insula predicted greater weight gain between baseline and 1-month post-randomisation and between baseline and 4-months post-randomisation.

CONCLUSIONS

This exploratory pilot study identified rTMS treatment related changes in CBF in adults with SE-AN and these were associated with changes in weight. Our preliminary findings also suggest that CBF (as measured by ASL fMRI) may be a marker of rTMS treatment response in this patient group. Future rTMS studies in AN should employ longitudinal neuroimaging to further explore the neurobiological changes related to rTMS treatment.

TRIAL REGISTRATION

ISRCTN14329415 , registered 23rd July 2015.

Resilience, pain, and the brain: Relationships differ by sociodemographics

Chronic musculoskeletal (MSK) pain is disabling to individuals and burdensome to society. A relationship between telomere length and resilience was reported in individuals with consideration for chronic pain intensity. While chronic pain associates with brain changes, little is known regarding the neurobiological interface of resilience. In a group of individuals with chronic MSK pain, we examined the relationships between a previously investigated resilience index, clinical pain and functioning measures, and pain-related brain structures, with consideration for sex and ethnicity/race. A cross-sectional analysis of 166 non-Hispanic Black and non-Hispanic White adults, 45-85 years of age with pain ≥ 1 body site (s) over the past 3 months was completed. Measures of clinical pain and functioning, biobehavioral and psychosocial resilience, and structural MRI were completed. Our findings indicate higher levels of resilience associate with lower levels of clinical pain and functional limitations. Significant associations between resilience, ethnicity/race, and/or sex, and pain-related brain gray matter structure were demonstrated in the right amygdaloid complex, bilateral thalamus, and postcentral gyrus. Our findings provide compelling evidence that in order to decipher the neurobiological code of chronic pain and related protective factors, it will be important to improve how chronic pain is phenotyped; to include an equal representation of females in studies including analyses stratifying by sex, and to consider other sociodemographic factors.

Asymmetry of amygdala resting-state functional connectivity in healthy human brain

Lateral asymmetry is one of the fundamental properties of the functional anatomy of the human brain. Amygdala (AMYG) asymmetry was also reported in clinical studies of resting-state functional connectivity (rsFC) but rarely in healthy groups. To explore this issue, we investigated the reproducibility of the data on rsFC of the left and right AMYG using functional MRI twice a week in 20 healthy volunteers with mild-to-moderate anxiety. We found a resting-state network of the AMYG, which included regions involved in emotional processing and several other brain areas associated with memory and motor inhibition. The AMYG network was stable in time and within subjects, but the right AMYG had more significant connections with anatomical brain regions. The rsFC values of the right AMYG were also more sustained across the week than the left AMYG rsFC. Subjective ratings of anxiety did not correlate significantly with the patterns of seed-based AMYG connectivity. Our findings indicate that, for healthy subjects, rsFC may differ for the right and left AMYG. Moreover, the AMYG functional connectivity is variable in short-term observations, which may also influence the results of longitude studies.

The manifestation of individual differences in sensitivity to punishment during resting state is modulated by eye state

Structural and functional neuroimaging studies have shown that brain areas associated with fear and anxiety (defensive system areas) are modulated by individual differences in sensitivity to punishment (SP). However, little is known about how SP is related to brain functional connectivity and the factors that modulate this relationship. In this study, we investigated whether a simple methodological manipulation, such as performing a resting state with eyes open or eyes closed, can modulate the manifestation of individual differences in SP. To this end, we performed an exploratory fMRI resting state study in which a group of participants (n = 88) performed a resting state with eyes closed and another group (n = 56) performed a resting state with eyes open. All participants completed the Sensitivity to Punishment and Sensitivity to Reward Questionnaire. Seed-based functional connectivity analyses were performed in the amygdala, hippocampus, and periaqueductal gray (PAG). Our results showed that the relationship between SP and left amygdala-precuneus and left hippocampus-precuneus functional connectivity was modulated by eye state. Moreover, in the eyes open group, SP was negatively related to the functional connectivity between the PAG and amygdala and between the PAG and left hippocampus, and it was positively related to the functional connectivity between the amygdala and hippocampus. Together, our results may suggest underlying differences in the connectivity between anxiety-related areas based on eye state, which in turn would affect the manifestation of individual differences in SP.

Functional connectivity associated with five different categories of Autonomous Sensory Meridian Response (ASMR) triggers

Autonomous sensory meridian response (ASMR) is a sensory-emotional phenomenon in which specific sensory stimuli ("ASMR triggers") reliably elicit feelings of relaxation and tingling sensations on the head, neck, and shoulders. However, there are individual differences in which stimuli elicit ASMR and in the intensity of these responses. In the current research, we used resting-state fMRI to examine the functional connectivity associated with these differences. Fifteen individuals with self-reported ASMR completed the ASMR Checklist, which measures sensitivity to different ASMR triggers, and a resting-state fMRI scan. Checklist scores were entered as covariates to determine whether the functional connectivity of eight resting-state networks differed as a function of participants' sensitivity to five categories of triggers. The results indicated unique patterns of functional connectivity associated with sensitivity to each ASMR trigger category. Sensitivity to two trigger categories was positively correlated with the dorsal attention network, suggesting that ASMR may involve atypical attentional processing.

Prefrontal-amygdala connectivity in trait anxiety and generalized anxiety disorder: Testing the boundaries between healthy and pathological worries

BACKGROUND

Current brain-based theoretical models of generalized anxiety disorder (GAD) suggest a dysfunction of amygdala-ventromedial prefrontal cortex emotional regulatory mechanisms. These alterations might be reflected by an altered resting state functional connectivity between both areas and could extend to vulnerable non-clinical samples such as high worriers without a GAD diagnosis. However, there is a lack of information in this regard.

METHODS

We investigated differences in resting state functional connectivity between the basolateral amygdala and the ventromedial prefrontal cortex (amygdala-vmPFC) in 28 unmedicated participants with GAD, 28 high-worriers and 28 low-worriers. We additionally explored selected clinical variables as predictors of amygdala-vmPFC connectivity, including anxiety sensitivity.

RESULTS

GAD participants presented higher left amygdala-vmPFC connectivity compared to both groups of non-GAD participants, and there were no differences between the latter two groups. In our exploratory analyses, concerns about the cognitive consequences of anxiety (the cognitive dimension of anxiety sensitivity) were found to be a significant predictor of the left amygdala-vmPFC connectivity.

LIMITATIONS

The cross-sectional nature of our study preclude us from assessing if functional connectivity measures and anxiety sensitivity scores entail an increased risk of GAD.

CONCLUSIONS

These results suggest a neurobiological qualitative distinction at the level of the amygdala-vmPFC emotional-regulatory system in GAD compared to non-GAD participants, either high- or low-worriers. At this neural level, they question previous hypotheses of continuity between high worries and GAD development. Instead, other anxiety traits such as anxiety sensitivity might confer a greater proneness to the amygdala-vmPFC connectivity alterations observed in GAD.

Individual Variables Involved in Perceived Pressure for Adolescent Drinking

Adolescence is a stage when individuals are especially vulnerable to the influence of their peer group, which could lead to the development of problematic behavior, such as drinking alcohol, due to perceived pressure. The objective of this study was to analyze the role of self-esteem, impulsivity, anxiety sensitivity and expectations for use under perceived pressure to drink alcohol among young people.

METHODS

The sample was made up of 1287 high school students aged 14 to 18, with a mean age of 15.11. The Bayes factor and mediation models were estimated to evaluate the data.

RESULTS

The results showed the existence of a positive relationship of impulsivity, anxiety sensitivity and expectations for use with perceived pressure. However, this relationship was negative with self-esteem and perception of pressure to drink alcohol. Furthermore, the model results showed that self-esteem mediates the relationship between physical, cognitive and social anxiety sensitivity and positive expectations with perceived pressure to drink alcohol in adolescence.

CONCLUSIONS

Given the strong need for affiliation during youth, it is hard to control grouping and peer influence on drinking behavior. However, knowledge of the role of individual variables, such as those described here, in perceived pressure could improve the prevention and intervention of such behaviors.

Threat-induced anxiety during goal pursuit disrupts amygdala-prefrontal cortex connectivity in posttraumatic stress disorder

To investigate how unpredictable threat during goal pursuit impacts fronto-limbic activity and functional connectivity in posttraumatic stress disorder (PTSD), we compared military veterans with PTSD (n = 25) vs. trauma-exposed control (n = 25). Participants underwent functional magnetic resonance imaging (fMRI) while engaged in a computerized chase-and-capture game task that involved optimizing monetary rewards obtained from capturing virtual prey while simultaneously avoiding capture by virtual predators. The game was played under two alternating contexts-one involving exposure to unpredictable task-irrelevant threat from randomly occurring electrical shocks, and a nonthreat control condition. Activation in and functional connectivity between the amygdala and ventromedial prefrontal cortex (vmPFC) was tested across threat and nonthreat task contexts with generalized psychophysiological interaction (gPPI) analyses. PTSD patients reported higher anxiety than controls across contexts. Better task performance represented by successfully avoiding capture by predators under threat compared with nonthreat contexts was associated with stronger left amygdala-vmPFC functional connectivity in controls and greater vmPFC activation in PTSD patients. PTSD symptom severity was negatively correlated with vmPFC activation in trauma-exposed controls and with right amygdala-vmPFC functional connectivity across all participants in the threat relative to nonthreat contexts. The findings showed that veterans with PTSD have disrupted amygdala-vmPFC functional connectivity and greater localized vmPFC processing under threat modulation of goal-directed behavior, specifically related to successfully avoiding loss of monetary rewards. In contrast, trauma survivors without PTSD relied on stronger threat-modulated left amygdala-vmPFC functional connectivity during goal-directed behavior, which may represent a resilience-related functional adaptation.

Effects of social subordination and oestradiol on resting-state amygdala functional connectivity in adult female rhesus monkeys

Preclinical studies demonstrate that chronic stress modulates the effects of oestradiol (E2) on behaviour through the modification of the amygdala and the medial prefrontal cortex (mPFC) neuronal structure. Clinical studies suggest that alterations in amygdala functional connectivity (FC) with the mPFC may be associated with stress-related phenotypes, including mood and anxiety disorders. Thus, identifying the effects of stress and E2 on amygdala-mPFC circuits is critical for understanding the neurobiology underpinning the vulnerability to stress-related disorders in women. In the present study, we used a well-validated rhesus monkey model of chronic psychosocial stress (subordinate social rank) to examine effects of E2 on subordinate (SUB) (i.e. high stress) and dominant (DOM) (i.e. low stress) female resting-state amygdala FC with the mPFC and with the whole-brain. In the non-E2 treatment control condition, SUB was associated with stronger left amygdala FC to subgenual cingulate (Brodmann area [BA] 25: BA25), a region implicated in several psychopathologies in people. In SUB females, E2 treatment strengthened right amygdala-BA25 FC, induced a net positive amygdala-visual cortex FC that was positively associated with frequency of submissive behaviours, and weakened positive amygdala-para/hippocampus FC. Our findings show that subordinate social rank alters amygdala FC and the impact of E2 on amygdala FC with BA25 and with regions involved in visual processing and memory encoding.

Anger provocation increases limbic and decreases medial prefrontal cortex connectivity with the left amygdala in reactive aggressive violent offenders

Neurobiological models propose reactive aggression as a failure in emotion regulation, caused by an imbalance between prefrontal cortical control and excessive bottom-up signals of negative affect by limbic regions, including the amygdala. Therefore, we hypothesize a negative correlation between PFC and amygdala activity (pre/post resting-state scans) in violent offenders. In this study resting-state fMRI was administered before and after an emotion (anger and happiness) provocation or engagement task within 18 male violent offenders scoring high on reactive aggression, and 18 male non-offender controls. Research in emotional pre/post resting-state showed altered connectivity by task performance. Therefore, bilateral amygdala region of interest (ROI) whole brain functional connectivity analysis tested dynamic change differences between pre and post resting-state connectivity between groups. Self-reported anger showed a positive significant relationship with medial prefrontal cortex activity in the pre-task scan and significantly increased during the emotion task in both the violent and control group. Imaging results showed a significant decrease in amygdala – medial prefrontal functional connectivity in the violent offenders and an increase in the non-offender controls after the emotion task. The opposite pattern was found for amygdala connectivity with the (para) limbic regions: violent offenders showed increased connectivity and non-offender controls showed decreased connectivity. The present results indicate that reactive aggression might stem from a focus on emotion processing, as indicated by an increase in limbic functional connectivity. The combination of a focus on emotion, along with a lack of medial prefrontal cortex regulation, has the potential to grow out of control e.g. in reactive aggression.

Left, right, or bilateral amygdala activation? How effects of smoothing and motion correction on ultra-high field, high-resolution functional magnetic resonance imaging (fMRI) data alter inferences

Given the amygdala's role in survival mechanisms, and its pivotal contributions to psychological processes, it is no surprise that it is one of the most well-studied brain regions. One of the common methods for understanding the functional role of the amygdala is the use of functional magnetic resonance imaging (fMRI). However, fMRI tends to be acquired using resolutions that are not optimal for smaller brain structures. Furthermore, standard processing includes spatial smoothing and motion correction which further degrade the resolution of the data. Inferentially, this may be detrimental when determining if the amygdalae are active during a task. Indeed, studies using the same task may show differential amygdala(e) activation. Here, we examine the effects of well-accepted preprocessing steps on whole-brain submillimeter fMRI data to determine the impact on activation patterns associated with a robust task known to activate the amygdala(e). We analyzed 7T fMRI data from 30 healthy individuals collected at sub-millimeter in-plane resolution and used a field standard preprocessing pipeline with different combinations of smoothing kernels and motion correction options. Resultant amygdalae activation patterns were altered depending on which combination of smoothing and motion correction were performed, indicating that whole-brain preprocessing steps have a significant impact on the inferences that can be drawn about smaller, subcortical structures like the amygdala.

Altered Effective Connectivity of Central Autonomic Network in Response to Negative Facial Expression in Adults With Cannabis Use Disorder

BACKGROUND

Cannabis use is associated with an increased risk of stress-related adverse cardiovascular events. Because brain regions of the central autonomic network largely overlap with brain regions related to the neural response to emotion and stress, the central autonomic network may mediate the autonomic response to negative emotional stimuli. We aimed to obtain evidence to determine whether neural connectivity of the central autonomic network is altered in individuals with cannabis use disorder (CUD) when they are exposed to negative emotional stimuli.

METHODS

Effective (directional) connectivity (EC) analysis using dynamic causal modeling was applied to functional magnetic resonance imaging data acquired from 23 subjects with CUD and 23 control subjects of the Human Connectome Project while they performed an emotional face-matching task with interleaving periods of negative-face (fearful/angry) and neutral-shape stimuli. The EC difference (modulatory change) was measured during the negative-face trials relative to the neutral-shape trials.

RESULTS

The CUD group was similar to the control group in nonimaging measures and brain activations but showed greater modulatory changes in left amygdala to hypothalamus EC (positively associated with Perceived Stress Scale score), right amygdala to bilateral fusiform gyri ECs (positively associated with Perceived Stress Scale score), and left ventrolateral prefrontal cortex to bilateral fusiform gyri ECs (negatively associated with Perceived Stress Scale score).

CONCLUSIONS

Left amygdala to hypothalamus EC and right amygdala to bilateral fusiform gyri ECs are possibly part of circuits underlying the risk of individuals with CUD to stress-related disorders. Correspondingly, left ventrolateral prefrontal cortex to bilateral fusiform gyri ECs are possibly part of circuits reflecting a protective mechanism.

The influence of High Dose Spinal Cord Stimulation on the descending pain modulatory system in patients with failed back surgery syndrome

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For the first time, the influence of HD-SCS on the descending pathways was tested.

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rsfMRI and functional connectivity were used to evaluate this a priori hypothesis.

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HD-SCS does influence the descending pain modulatory system.

The role of BDNF methylation and Val66 Met in amygdala reactivity during emotion processing

Epigenetic alterations of the brain-derived neurotrophic factor (BDNF) gene have been associated with psychiatric disorders in humans and with differences in amygdala BDNF mRNA levels in rodents. This human study aimed to investigate the relationship between the functional BDNF-Val⁶⁶ Met polymorphism, its surrounding DNA methylation in BDNF exon IX, amygdala reactivity to emotional faces, and personality traits. Healthy controls (HC, n = 189) underwent functional MRI during an emotional face-matching task. Harm avoidance, novelty seeking and reward dependence were measured using the Tridimensional Personality Questionnaire (TPQ). Individual BDNF methylation profiles were ascertained and associated with several BDNF single nucleotide polymorphisms surrounding the BDNF-Val⁶⁶ Met, amygdala reactivity, novelty seeking and harm avoidance. Higher BDNF methylation was associated with higher amygdala reactivity (x = 34, y = 0, z = -26, t₍₁₆₆₎ = 3.00, TFCE = 42.39, p_(FWE) = .045), whereby the BDNF-Val⁶⁶ Met genotype per se did not show any significant association with brain function. Furthermore, novelty seeking was negatively associated with BDNF methylation (r = -.19, p = .015) and amygdala reactivity (r = -.17, p = .028), while harm avoidance showed a trend for a positive association with BDNF methylation (r = .14, p = .066). The study provides first insights into the relationship among BDNF methylation, BDNF genotype, amygdala reactivity and personality traits in humans, highlighting the multidimensional relations among genetics, epigenetics, and neuronal functions. The present study suggests a possible involvement of epigenetic BDNF modifications in psychiatric disorders and related brain functions, whereby high BDNF methylation might reduce BDNF mRNA expression and upregulate amygdala reactivity.

Brain functional connectivity in headache disorders: A narrative review of MRI investigations

Resting-state functional magnetic resonance imaging (rs-fMRI) is used to interrogate the functional connectivity and network organization amongst brain regions. Functional connectivity is determined by measuring the extent of synchronization in the spontaneous fluctuations of blood oxygenation level dependent (BOLD) signal. Here, we review current rs-fMRI studies in headache disorders including migraine, trigeminal autonomic cephalalgias, and medication overuse headache. We discuss (1) brain network alterations that are shared amongst the different headache disorders and (2) network abnormalities distinct to each headache disorder. In order to focus the section on migraine, the headache disorder that has been most extensively studied, we chose to include articles that interrogated functional connectivity: (i) during the attack phase; (ii) in migraine patients with aura compared to migraine patients without aura; and (iii) of regions within limbic, sensory, motor, executive and default mode networks and those which participate in multisensory integration. The results of this review show that headache disorders are associated with atypical functional connectivity of regions associated with pain processing as well as atypical functional connectivity of multiple core resting state networks such as the salience, sensorimotor, executive, attention, limbic, visual, and default mode networks.

Dopaminergic Mechanisms Underlying Normal Variation in Trait Anxiety

Trait anxiety has been associated with altered activity within corticolimbic pathways connecting the amygdala and rostral anterior cingulate cortex (rACC), which receive rich dopaminergic input. Though the popular culture uses the term "chemical imbalance" to describe the pathophysiology of psychiatric conditions such as anxiety disorders, we know little about how individual differences in human dopamine neurochemistry are related to variation in anxiety and activity within corticolimbic circuits. We addressed this issue by examining interindividual variability in dopamine release at rest using [¹¹C]raclopride positron emission tomography (PET), functional connectivity between amygdala and rACC using resting-state functional magnetic resonance imaging (fMRI), and trait anxiety measures in healthy adult male and female humans. To measure endogenous dopamine release, we collected two [¹¹C]raclopride PET scans per participant. We contrasted baseline [¹¹C]raclopride D2/3 receptor binding and D2/3 receptor binding following oral methylphenidate administration. Methylphenidate blocks the dopamine transporter, which increases extracellular dopamine and leads to reduced [¹¹C]raclopride D2/3 receptor binding via competitive displacement. We found that individuals with higher dopamine release in the amygdala and rACC self-reported lower trait anxiety. Lower trait anxiety was also associated with reduced rACC-amygdala functional connectivity at baseline. Further, functional connectivity showed a modest negative relationship with dopamine release such that reduced rACC-amygdala functional connectivity was accompanied by higher levels of dopamine release in these regions. Together, these findings contribute to hypodopaminergic models of anxiety and support the utility of combining fMRI and PET measures of neurochemical function to advance our understanding of basic affective processes in humans.SIGNIFICANCE STATEMENT It is common wisdom that individuals vary in their baseline levels of anxiety. We all have a friend or colleague we know to be more "tightly wound" than others, or, perhaps, we are the ones marveling at others' ability to "just go with the flow." Although such observations about individual differences within nonclinical populations are commonplace, the neural mechanisms underlying normal variation in trait anxiety have not been established. Using multimodal brain imaging in humans, this study takes initial steps in linking intrinsic measures of neuromodulator release and functional connectivity within regions implicated in anxiety disorders. Our findings suggest that in healthy adults, higher levels of trait anxiety may arise, at least in part, from reduced dopamine neurotransmission.

Resting-state functional brain connectivity best predicts the personality dimension of openness to experience

Personality neuroscience aims to find associations between brain measures and personality traits. Findings to date have been severely limited by a number of factors, including small sample size and omission of out-of-sample prediction. We capitalized on the recent availability of a large database, together with the emergence of specific criteria for best practices in neuroimaging studies of individual differences. We analyzed resting-state functional magnetic resonance imaging data from 884 young healthy adults in the Human Connectome Project (HCP) database. We attempted to predict personality traits from the "Big Five", as assessed with the NEO-FFI test, using individual functional connectivity matrices. After regressing out potential confounds (such as age, sex, handedness and fluid intelligence), we used a cross-validated framework, together with test-retest replication (across two sessions of resting-state fMRI for each subject), to quantify how well the neuroimaging data could predict each of the five personality factors. We tested three different (published) denoising strategies for the fMRI data, two inter-subject alignment and brain parcellation schemes, and three different linear models for prediction. As measurement noise is known to moderate statistical relationships, we performed final prediction analyses using average connectivity across both imaging sessions (1 h of data), with the analysis pipeline that yielded the highest predictability overall. Across all results (test/retest; 3 denoising strategies; 2 alignment schemes; 3 models), Openness to experience emerged as the only reliably predicted personality factor. Using the full hour of resting-state data and the best pipeline, we could predict Openness to experience (NEOFAC_O: r=0.24, R2=0.024) almost as well as we could predict the score on a 24-item intelligence test (PMAT24_A_CR: r=0.26, R2=0.044). Other factors (Extraversion, Neuroticism, Agreeableness and Conscientiousness) yielded weaker predictions across results that were not statistically significant under permutation testing. We also derived two superordinate personality factors ("α" and "β") from a principal components analysis of the NEO-FFI factor scores, thereby reducing noise and enhancing the precision of these measures of personality. We could account for 5% of the variance in the β superordinate factor (r=0.27, R2=0.050), which loads highly on Openness to experience. We conclude with a discussion of the potential for predicting personality from neuroimaging data and make specific recommendations for the field.

Altered Gray Matter Volume and Its Correlation With PTSD Severity in Chinese Earthquake Survivors

Objective: To detect the changes of gray matter volume (GMV) and their correlation with severity of symptom in patients with post-traumatic stress disorder (PTSD) who were defined with updated DSM-5 diagnostic criteria. Method: 71 participants were assigned into PTSD group (n = 35) or trauma-exposed control (TEC) group (n = 36) with the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Voxel-based morphometry analysis was used to detect alterations in GMV in the PTSD group. Results: We found that the PTSD group had larger GMV in the left middle temporal gyrus (MTG) and in the right dorsal medial prefrontal cortex (dmPFC), and smaller GMV in the region of the right temporal pole (TP) than the TEC group. We also found that PTSD Checklist for DSM-5 (PCL-5) scores correlated positively with the left MTG and right dmPFC GMV, and negatively with left TP GMV. These correlations were consistent with the findings of the between-group comparisons. Conclusions: GMV alterations in the MTG, dmPFC, and TP are detected in the group comparisons and correlated with symptom severity when classifying PTSD individuals according to DSM-5 diagnostic criteria within an earthquake-exposed population.

Temperament and character in patients with systemic lupus erythematosus

BACKGROUND

In addition to identified neuropsychiatric characteristic of systemic lupus erythematosus (SLE), changes in personality seem to occur in patients with SLE. Even in absence of an axis I psychiatric diagnosis, personality variations play important role in general wellbeing of these patients. This study investigated personality features in patients with SLE using Temperament and Character Inventory (TCI).

METHOD

In this case-control study personality features of 59 patients with confirmed diagnosis of SLE were evaluated using Persian version of TCI-125 questionnaire. Collected data from patients with SLE were statistically compared with normative data for Iranian population.

RESULTS

Among four subscales of temperament, reward dependence (RD) and harm-avoidance (HA) were significantly lower than general population. Self-directedness (SD) character dimension was significantly lower in SLE patients compared to normative data. No significant difference was noted in novelty-seeking (NS) and persistence (PS) temperament scales and cooperativeness (CO) and self-transcendence (ST) character scales.

CONCLUSION

Personality changes in SLE is characterized by higher HA and RD along with low SD. These features are associated with higher anxiety, social withdrawal and lower resourcefulness and purposefulness.

Altered Amygdala Resting-State Functional Connectivity and Hemispheric Asymmetry in Patients With Social Anxiety Disorder

Background: The amygdala plays a key role in emotional hyperreactivity in response to social threat in patients with social anxiety disorder (SAD). We investigated resting-state functional connectivity (rs-FCN) of the left and right amygdala with various brain regions and functional lateralization in patients with SAD. Methods: A total of 36 patients with SAD and 42 matched healthy controls underwent functional magnetic resonance imaging (fMRI) at rest. Using the left and right amygdala as seed regions, we compared the strength of the rs-FCN in the patient and control groups. Furthermore, we investigated group differences in the hemispheric asymmetry of the functional connectivity maps of the left and right amygdala. Results: Compared with healthy controls, the rs-FCN between the left amygdala and the dorsolateral prefrontal cortex was reduced in patients with SAD, whereas left amygdala connectivity with the fusiform gyrus, anterior insula, supramarginal gyrus, and precuneus was increased or positively deflected in the patient group. Additionally, the strength rs-FCN between the left amygdala and anterior insula was positively associated with the severity of the fear of negative evaluation in patients with SAD (r = 0.338, p = 0.044). The rs-FCN between the right amygdala and medial frontal gyrus was decreased in patients with SAD compared with healthy controls, whereas connectivity with the parahippocampal gyrus was greater in the patient group than in the control group. The hemispheric asymmetry patterns in the anterior insula, intraparietal sulcus (IPS), and inferior frontal gyrus of the patient group were opposite those of the control group, and functional lateralization of the connectivity between the amygdala and the IPS was associated with the severity of social anxiety symptoms (r = 0.365, p = 0.037). Conclusion: Our findings suggest that in addition to impaired fronto-amygdala communication, the functional lateralization of amygdala function plays a central role in the pathophysiology of SAD.

Serotonin-1A receptor C-1019G polymorphism affects brain functional networks

The serotonin-1A (5-HT1A) receptor is strongly implicated in major depression and other affective disorders due to its negative regulation of serotonin neurone firing rates. Behavioural and clinical studies have repeatedly reported that the −1019G allele carries a high susceptibility for affective disorders. However, the underlying pathophysiology remains unknown. Here, we employed a genetic neuroimaging strategy in 99 healthy human subjects to explore the effect of serotonin-1A receptor polymorphism on brain resting-state functional connectivity (FC). We used functional magnetic resonance imaging, along with a seed-based approach, to identify three main brain networks: the default mode network (DMN), the salience network (SN) and the central executive network. We observed a significant decrease in the FC of the DMN within the dorsolateral and ventromedial prefrontal cortices in G-carriers. Furthermore, compared with the C-homozygote group, we observed decreased FC of the SN within the ventromedial prefrontal cortex and subgenual anterior cingulate cortex in the G-carrier group. Our results indicate that 5-HT1A receptor genetic polymorphism modulates the activity of resting-state FC within brain networks including the DMN and SN. These genotype-related alterations in brain networks and FC may provide novel insights into the neural mechanism underlying the predisposition for affective disorders in G allele carriers.

Resting-state brain connectivity changes in obese women after Roux-en-Y gastric bypass surgery: A longitudinal study

Bariatric surgery is an effective method to rapidly induce weight loss in severely obese people, however its impact on brain functional connectivity after longer periods of follow-up is yet to be assessed. We investigated changes in connectivity in 16 severely obese women one month before, one month after and one year after Roux-en-Y gastric bypass surgery (RYGB). 12 lean controls were also enrolled. Resting-state fMRI was acquired for all participants following an overnight fast and after a 260 kcal load. Connectivity between regions involved in food-related saliency attribution and reward-driven eating behavior was stronger in presurgery patients compared to controls, but progressively weakened after follow-up. At one year, changes in networks related to cognitive control over eating and bodily perception also occurred. Connectivity between regions involved in emotional control and social cognition had a temporary reduction early after treatment but had increased again after one year of follow-up. Furthermore, we could predict the BMI loss by presurgery connectivity in areas linked to emotional control and social interaction. RYGBP seems to reshape brain functional connectivity, early affecting cognitive control over eating, and these changes could be an important part of the therapeutic effect of bariatric surgery.

Neonatal Amygdala Functional Connectivity at Rest in Healthy and Preterm Infants and Early Internalizing Symptoms

OBJECTIVE

Alterations in the normal developmental trajectory of amygdala resting state functional connectivity (rs-FC) have been associated with atypical emotional processes and psychopathology. Little is known, however, regarding amygdala rs-FC at birth or its relevance to outcomes. This study examined amygdala rs-FC in healthy, full-term (FT) infants and in very preterm (VPT) infants, and tested whether variability of neonatal amygdala rs-FC predicted internalizing symptoms at age 2 years.

METHOD

Resting state fMRI data were obtained shortly after birth from 65 FT infants (gestational age [GA] ≥36 weeks) and 57 VPT infants (GA <30 weeks) at term equivalent. Voxelwise correlation analyses were performed using individual-specific bilateral amygdala regions of interest. Total internalizing symptoms and the behavioral inhibition, depression/withdrawal, general anxiety, and separation distress subdomains were assessed in a subset (n = 44) at age 2 years using the Infant Toddler Social Emotional Assessment.

RESULTS

In FT and VPT infants, the amygdala demonstrated positive correlations with subcortical and limbic structures and negative correlations with cortical regions, although magnitudes were decreased in VPT infants. Neonatal amygdala rs-FC predicted internalizing symptoms at age 2 years with regional specificity consistent with known pathophysiology in older populations: connectivity with the anterior insula related to depressive symptoms, with the dorsal anterior cingulate related to generalized anxiety, and with the medial prefrontal cortex related to behavioral inhibition.

CONCLUSION

Amygdala rs-FC is well established in neonates. Variability in regional neonatal amygdala rs-FC predicted internalizing symptoms at 2 years, suggesting that risk for internalizing symptoms may be established in neonatal amygdala functional connectivity patterns.

Dissociation between amygdala and bed nucleus of the stria terminalis during threat anticipation in female post-traumatic stress disorder patients

Feelings of uncontrollability and anxiety regarding possibly harmful events are key features of post-traumatic stress disorder (PTSD) symptomatology. Due to a lack of studies, the neural correlates of anticipatory anxiety in PTSD are still poorly understood. During functional magnetic resonance imaging, female PTSD patients with interpersonal violence trauma and healthy controls (HC) anticipated the temporally unpredictable presentation of aversive (human scream) or neutral sounds. Based on separate analysis models, we investigated phasic and sustained brain activations. PTSD patients reported increased anxiety during anticipation of aversive versus neutral sounds. Furthermore, we found both increased initial, phasic amygdala activation and increased sustained activation of the bed nucleus of the stria terminalis (BNST) during anticipation of aversive versus neutral sounds in PTSD patients in comparison to HC. PTSD patients as compared with HC also showed increased phasic responses in mid-cingulate cortex (MCC), posterior cingulate cortex (PCC), mid-insula and lateral prefrontal cortex (PFC) as well as increased sustained responses in MCC, PCC, anterior insula and lateral and medial PFC. Our results demonstrate a relationship between anticipatory anxiety in PTSD patients and hyperresponsiveness of brain regions that have previously been associated with PTSD symptomatology. Additionally, the dissociation between amygdala and BNST indicates distinct temporal and functional characteristics and suggests that phasic fear and sustained anxiety responses are enhanced during unpredictable anticipation of aversive stimuli in PTSD. Hum Brain Mapp 38:2190-2205, 2017. © 2017 Wiley Periodicals, Inc.

Abnormal effective fronto-limbic connectivity during emotion processing in schizophrenia

BACKGROUND

Schizophrenia is associated with core emotional dysfunctions. At the neural level, functional neuro-imaging studies have highlighted fronto-limbic alterations during emotion processing in schizophrenia, as well as impaired connectivity between the amygdala and the prefrontal cortex. However, the direction of the impaired fronto-limbic connections remains largely unknown. To clarify this issue, we performed an effective connectivity study on emotion processing in schizophrenia.

METHODS

Forty-one healthy individuals and 39 schizophrenia patients (DSM-IV criteria) viewed negative, positive and neutral images during an fMRI session. Effective connectivity between significantly activated regions was examined using Granger causality and psychophysical interaction analyses.

RESULTS

Subjective ratings of emotionally neutral images were higher in schizophrenia patients than in controls. Across groups, significant activations were observed in the dorso-medial prefrontal cortex (dmPFC) and the bilateral amygdala. The Granger connectivity from the right amygdala to the dmPFC was significantly reduced in schizophrenia patients, relative to controls, during the negative and neutral conditions. The Granger connectivity from the left amygdala to the dmPFC was significantly reduced in schizophrenia patients, relative to controls, during the positive condition.

DISCUSSION

The finding of a reduced lagged connectivity from the bilateral amygdala to the dmPFC in schizophrenia suggests that the bottom-up mechanisms involved in the processing of highly arousing emotional stimuli are impaired in this disorder. The finding of an impaired lagged connectivity from the right amygdala to the dmPFC during the processing of emotionally neutral stimuli in schizophrenia is novel and may explain why these patients tend to confer emotional significance to irrelevant stimuli.

Variation in the Williams syndrome GTF2I gene and anxiety proneness interactively affect prefrontal cortical response to aversive stimuli

Characterizing the molecular mechanisms underlying the heritability of complex behavioral traits such as human anxiety remains a challenging endeavor for behavioral neuroscience. Copy-number variation (CNV) in the general transcription factor gene, GTF2I, located in the 7q11.23 chromosomal region that is hemideleted in Williams syndrome and duplicated in the 7q11.23 duplication syndrome (Dup7), is associated with gene-dose-dependent anxiety in mouse models and in both Williams syndrome and Dup7. Because of this recent preclinical and clinical identification of a genetic influence on anxiety, we examined whether sequence variation in GTF2I, specifically the single-nucleotide polymorphism rs2527367, interacts with trait and state anxiety to collectively impact neural response to anxiety-laden social stimuli. Two hundred and sixty healthy adults completed the Tridimensional Personality Questionnaire Harm Avoidance (HA) subscale, a trait measure of anxiety proneness, and underwent functional magnetic resonance imaging (fMRI) while matching aversive (fearful or angry) facial identity. We found an interaction between GTF2I allelic variations and HA that affects brain response: in individuals homozygous for the major allele, there was no correlation between HA and whole-brain response to aversive cues, whereas in heterozygotes and individuals homozygous for the minor allele, there was a positive correlation between HA sub-scores and a selective dorsolateral prefrontal cortex (DLPFC) responsivity during the processing of aversive stimuli. These results demonstrate that sequence variation in the GTF2I gene influences the relationship between trait anxiety and brain response to aversive social cues in healthy individuals, supporting a role for this neurogenetic mechanism in anxiety.

Emotion regulation in disordered eating: Psychometric properties of the Difficulties in Emotion Regulation Scale among Spanish adults and its interrelations with personality and clinical severity

Objective: The aims of the study were to (1) validate the Difficulties in Emotion Regulation Scale (DERS) in a sample of Spanish adults with and without eating disorders, and (2) explore the role of emotion regulation difficulties in eating disorders (ED), including its mediating role in the relation between key personality traits and ED severity.

Methods: One hundred and thirty four patients (121 female, mean age = 29 years) with anorexia nervosa (n = 30), bulimia nervosa (n = 54), binge eating (n = 20), or Other Specified Feeding or Eating Disorders (n = 30) and 74 healthy control participants (51 female, mean age = 21 years) reported on general psychopathology, ED severity, personality traits and difficulties in emotion regulation. Exploratory and confirmatory factor analyses were conducted to examine the psychometrics of the DERS in this Spanish sample (Aim 1). Additionally, to examine the role of emotion regulation difficulties in ED (Aim 2), differences in emotion regulation difficulties across eating disorder subgroups were examined and structural equation modeling was used to explore the interrelations among emotion regulation, personality traits, and eating disorder severity.

Results: Results support the validity and reliability of the DERS within this Spanish adult sample and suggest that this measure has a similar factor structure in this sample as in the original sample. Moreover, emotion regulation difficulties were found to differ as a function of eating disorder subtype and to mediate the relation between two specific personality traits (i.e., high harm avoidance and low self-directedness) and ED severity.

Conclusions: Personality traits of high harm avoidance and low self-directedness may increase vulnerability to ED pathology indirectly, through emotion regulation difficulties.

Emotion regulation ability varies in relation to intrinsic functional brain architecture

This study investigated the neural basis of individual variation in emotion regulation, specifically the ability to reappraise negative stimuli so as to down-regulate negative affect. Brain functions in young adults were measured with functional Magnetic Resonance Imaging during three conditions: (i) attending to neutral pictures; (ii) attending to negative pictures and (iii) reappraising negative pictures. Resting-state functional connectivity was measured with amygdala and dorsolateral prefrontal cortical (DLPFC) seed regions frequently associated with emotion regulation. Participants reported more negative affect after attending to negative than neutral pictures, and less negative affect following reappraisal. Both attending to negative vs neutral pictures and reappraising vs attending to negative pictures yielded widespread activations that were significantly right-lateralized for attending to negative pictures and left-lateralized for reappraising negative pictures. Across participants, more successful reappraisal correlated with less trait anxiety and more positive daily emotion, greater activation in medial and lateral prefrontal regions, and lesser resting-state functional connectivity between (a) right amygdala and both medial prefrontal and posterior cingulate cortices, and (b) bilateral DLPFC and posterior visual cortices. The ability to regulate emotion, a source of resilience or of risk for distress, appears to vary in relation to differences in intrinsic functional brain architecture.

COMT Val(158)Met genotypes differentially influence subgenual cingulate functional connectivity in healthy females

Brain imaging studies have consistently shown subgenual Anterior Cingulate Cortical (sgACC) involvement in emotion processing. catechol-O-methyltransferase (COMT) Val(158) and Met(158) polymorphisms may influence such emotional brain processes in specific ways. Given that resting-state fMRI (rsfMRI) may increase our understanding on brain functioning, we integrated genetic and rsfMRI data and focused on sgACC functional connections. No studies have yet investigated the influence of the COMT Val(158)Met polymorphism (rs4680) on sgACC resting-state functional connectivity (rsFC) in healthy individuals. A homogeneous group of 61 Caucasian right-handed healthy female university students, all within the same age range, underwent rsfMRI. Compared to Met(158) homozygotes, Val(158) allele carriers displayed significantly stronger rsFC between the sgACC and the left parahippocampal gyrus, ventromedial parts of the inferior frontal gyrus (IFG), and the nucleus accumbens (NAc). On the other hand, compared to Val(158) homozygotes, we found in Met(158) allele carriers stronger sgACC rsFC with the medial frontal gyrus (MFG), more in particular the anterior parts of the medial orbitofrontal cortex. Although we did not use emotional or cognitive tasks, our sgACC rsFC results point to possible distinct differences in emotional and cognitive processes between Val(158) and Met(158) allele carriers. However, the exact nature of these directions remains to be determined.