Psychological, endocrine and neural responses to social evaluation in subclinical depression

Hippocampal volume maximally modulates the relationship between subsyndromal symptomatic depression and cognitive impairment in non-demented older adults

BACKGROUND

Subsyndromal symptomatic depression (SSD) is associated with an elevated risk of cognitive impairment in non-demented older adults. Given that hippocampal and middle temporal gyrus atrophy have been shown to cause SSD, our study aimed to investigate the effect of hippocampal volume on the association between SSD and cognitive impairment.

METHODS

338 non-demented older adults from the ADNI (Alzheimer's Disease Neuroimaging Initiative) cohort who underwent cognitive assessments, questionnaires on depressive symptoms and MRI brain were studied. SSD group is defined as a score of 1-5 based on Geriatric Depression Scale scores. We conducted causal mediation analyses to investigate the effect of hippocampal volume on cognitive performance cross-sectionally.

RESULTS

The SSD group displayed lower left and right hippocampal volume (p<0.01) than the non-SSD group. SSD was linked to poorer cognition and smaller hippocampal volume. We found that hippocampal volume partially mediated the effect of SSD on cognitive performance including the global cognition and the cognitive section of Alzheimer's Disease Assessment Scale, with mediation percentages ranging from 6.45 % to 30.46 %. In addition, we found that the thickness of the left middle temporal, right entorhinal and right fusiform gyrus, brain regions linked to AD, mediate the relationship between SSD and cognition with mediation percentages ranging from 8.67 % to 21.44 %.

LIMITATIONS

Our article didn't differentiate between mild cognitive impairment and normal population.

CONCLUSION

The associations of SSD and cognitive impairment are linked to alterations in Alzheimer's Disease related brain regions.

Prefrontal cortex activation and working memory performance in individuals with non-clinical depression: Insights from fNIRS

Previous research has extensively explored cognitive and neural deficits in clinically diagnosed depression, but the early stages of depression, where symptoms do not meet clinical thresholds, are less explored. This study investigated neurocognitive markers in individuals with non-clinical depression. The study assessed working memory (WM) performance and hemodynamic responses of prefrontal cortex (PFC) in 30 individuals with non-clinical depression and 41 healthy controls using two-back tasks with four stimulus types: numbers, letters, shapes, and emotional facial expressions. Hemodynamic responses were measured via oxyhemoglobin (HbO) using functional near-infrared spectroscopy. Results showed that individuals with non-clinical depression have significantly lower WM performance compare to healthy controls, particularly for shape- and emotional facial expression-based tasks. No differences were observed for the number- and letter- based tasks. Additionally, individual with non-clinical depression exhibited elevated HbO levels, indicating increased PFC activation. Specifically, significant HbO differences observed in the bilateral ventrolateral PFC during shape-based tasks, and in the left medial, bilateral orbital, and bilateral ventrolateral PFCs during emotional facial expression-based tasks. In conclusion, individuals with non-clinical depression may experience WM deficits and PFC dysregulation, even without a clinical diagnosis. This study highlights the role of stimulus type in understanding WM performance and PFC activation in depression.

Neural activation signatures in individuals with subclinical depression: A task-fMRI meta-analysis

BACKGROUND

Previous task-related functional magnetic resonance imaging (task-fMRI) investigations have documented abnormal brain activation associated with subclinical depression (SD), defined as a clinically relevant level of depressive symptoms that does not meet the diagnostic criteria for major depressive disorder. However, these task-fMRI studies have not reported consistent conclusions. Performing a voxel-based meta-analysis of task-fMRI studies may yield reliable findings.

METHODS

We extracted the peak coordinates and t values of included studies and analyzed brain activation between individuals with SD and healthy controls (HCs) using anisotropic effect-size signed differential mapping (AES-SDM).

RESULTS

A systematic literature search identified eight studies, including 266 individuals with SD and 281 HCs (aged 14 to 25). The meta-analysis showed that individuals with SD exhibited significantly greater activation in the right lenticular nucleus and putamen according to task-fMRI. The meta-regression analysis revealed a negative correlation between the proportion of females in a group and activation in the right striatum.

LIMITATIONS

The recruitment criteria for individuals with SD, type of tasks and MRI acquisition parameters of included studies were heterogeneous. The results should be interpreted cautiously due to insufficient included studies.

CONCLUSION

Our findings suggest that individuals with SD exhibit increased activation in the right lenticular nucleus, putamen and striatum, which may indicate a compensatory increase in response to an impairment of insular and striatal function caused by depression. These results provide valuable insights into the potential pathophysiology of brain dysfunction in SD.

Structural and functional brain alterations in subthreshold depression: A multimodal coordinate-based meta-analysis

Imaging studies of subthreshold depression (StD) have reported structural and functional abnormalities in a variety of spatially diverse brain regions. However, there is no consensus among different studies. In the present study, we applied a multimodal meta-analytic approach, the Activation Likelihood Estimation (ALE), to test the hypothesis that StD exhibits spatially convergent structural and functional brain abnormalities compared to healthy controls. A total of 31 articles with 25 experiments were included, collectively representing 1001 subjects with StD. We found consistent differences between StD and healthy controls mainly in the left insula across studies with various neuroimaging methods. Further exploratory analyses found structural atrophy and decreased functional activities in the right pallidum and thalamus in StD, and abnormal spontaneous activity converged to the middle frontal gyrus. Coordinate-based meta-analysis found spatially convergent structural and functional impairments in StD. These findings provide novel insights for understanding the neural underpinnings of subthreshold depression and enlighten the potential targets for its early screening and therapeutic interventions in the future.

Neural and cortisol responses to acute psychosocial stress in work-related burnout: The Regensburg Burnout Project

BACKGROUND

While several attempts have been made to elucidate the pathophysiology of burnout, neural stress responses have not yet been investigated. Therefore, the aim of this study was to examine salivary cortisol and - for the first time - neural responses to acute psychosocial stress within a strictly specified sample consisting of individuals suffering from burnout (BO group) and a healthy comparison group (HC group).

METHODS

After a multi-stage recruitment procedure based on burnout symptomatology and pathogenesis, 55 individuals suffering from burnout (25 women) and 61 individuals serving as HC group (31 women) out of an initial sample of 1022 volunteers were exposed to acute psychosocial stress during functional magnetic resonance imaging (fMRI) applying ScanSTRESS.

RESULTS

No differences were found between the BO and the HC group with respect to cortisol and mean neural stress responses. However, an exploratory comparison of neural stress responses of the first and second run of ScanSTRESS (exposure-time effect) revealed group-specific response patterns in one cluster peaking in the left dorsal anterior cingulate cortex (dACC). While the neural activation of the HC group was higher in the first compared to the second run of ScanSTRESS (i.e., decreasing activation), this pattern was reversed in the BO group (i.e., increasing activation).

CONCLUSIONS

Our analysis mainly did not provide evidence for altered acute cortisol and mean neural stress responses in burnout. However, the BO group was characterized by a limited capacity to show decreasing activation over stress exposure-time and exhibited instead increasing activation. Importantly, this group difference manifested in the left dACC which is both involved in neural stress processing and affected in individuals suffering from burnout. Given the present results, it seems promising to further examining temporal dynamics of neural stress responses in (sub-) clinical conditions such as burnout.

Children's neural reactivity to maternal praise and criticism: Associations with early depressive symptoms and maternal depression

Caregiving experiences are implicated in children's depression risk; however, children's neural reactivity to positive and negative feedback from mothers, a potential mediator of depression risk, is poorly understood. In a sample of 81 children (Mage = 11.12 years, SDage = 0.63), some of whom were recruited based on a maternal history of depression (n = 29), we used fMRI to characterize children's neural responses to maternal praise and criticism. Maternal history of depression was unrelated to children's brain activity during both the praise and criticism conditions; however, ROI analyses showed that children's self-reported depressive symptoms were negatively associated with functional activity in the left anterior insula and right putamen while hearing maternal criticism. Whole-brain analyses showed that children's depressive symptoms were positively associated with left inferior frontal gyrus activity while listening to maternal praise. These findings complement past work implicating these brain regions in the processing of emotionally salient stimuli, reward processing, and internal speech. Given associations between early depressive symptoms and later disorder, findings suggest that maladaptive neural processing of maternal feedback may contribute to children's early emerging risk for depression.

Neural correlations between cognitive deficits and emotion regulation strategies: understanding emotion dysregulation in depression from the perspective of cognitive control and cognitive biases

The link between cognitive function and emotion regulation may be helpful in better understanding the onset, maintenance, and treatment for depression. However, it remains unclear whether there are neural correlates between emotion dysregulation and cognitive deficits in depression. To address this question, we first review the neural representations of emotion dysregulation and cognitive deficits in depression (including deficits in cognitive control and cognitive biases). Based on the comparisons of neural representations of emotion dysregulation versus cognitive deficits, we propose an accessible and reasonable link between emotion dysregulation, cognitive control, and cognitive biases in depression. Specifically, cognitive control serves the whole process of emotion regulation, whereas cognitive biases are engaged in emotion regulation processes at different stages. Moreover, the abnormal implementation of different emotion regulation strategies in depression is consistently affected by cognitive control, which is involved in the dorsolateral, the dorsomedial prefrontal cortex, and the anterior cingulate cortex. Besides, the relationship between different emotion regulation strategies and cognitive biases in depression may be distinct: the orbitofrontal cortex contributes to the association between ineffective reappraisal and negative interpretation bias, while the subgenual prefrontal cortex and the posterior cingulate cortex underline the tendency of depressed individuals to ruminate and overly engage in self-referential bias. This review sheds light on the relationship between cognitive deficits and emotion dysregulation in depression and identifies directions in need of future attention.

Neural and peripheral markers of reward during positive social evaluation are associated with less clinician-rated depression symptom severity in adolescence

Although blunted sensitivity to reward is thought to play a key role in promoting risk for depression, most research on this topic has utilized monetary reward paradigms and focused on currently depressed adults. To address this issue, we analyzed neural reward and β-endorphin data from the Psychobiology of Stress and Adolescent Depression (PSY SAD) Study, which recruited a well-characterized sample of adolescent girls at high vs. low risk for major depressive disorder (MDD) (N = 52, M age = 14.90, SD = 1.35) based on their mothers' lifetime history of MDD. As hypothesized, greater striatal activity while receiving positive (vs. neutral) social evaluation was associated with lower depression symptom severity as independently assessed by the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS). This association was present for girls at high but not low risk for MDD, suggesting that this neural response may represent a pre-clinical marker of risk for depression. Consistent with these results, higher post-social evaluation levels of a peripheral marker of reward sensitivity, β-endorphin, were related to lower clinician-rated depression symptom severity. Together, these results indicate that neural and peripheral markers of responsivity to social reward are both related to depression severity, which may have implications for understanding the pathophysiology of depression.

Sex-specific neural responses to acute psychosocial stress in depression

Major Depressive Disorder (MDD) is characterized by increased stress sensitivity. Emerging findings in healthy adults suggest that stress responses within limbic/striatal-prefrontal regions are moderated by sex and unfold over time. Thus, we hypothesized that stress response abnormalities in MDD might be affected by sex and stress exposure time. The Montreal Imaging Stress Task was administered to 124 unmedicated patients with first-episode MDD (76 females) and 243 healthy controls (HC; 137 females) during functional magnetic resonance imaging (fMRI). Based on prior studies, amygdala, hippocampus, medial orbitofrontal cortex (mOFC), nucleus accumbens (NAc) and dorsolateral prefrontal cortex (dlPFC) were selected as a priori regions of interest. In a complementary approach, we probed the effects of stress on the frontoparietal network (FPN) and a network including the amygdala, NAc and anterior cingulate cortex (ACC). Across groups, males exhibited higher dlPFC activity and right FPN amplitude than females. Relative to female HCs, the female MDD group had less deactivation in limbic/striatal regions (amygdala, NAc, hippocampus, Amygdala-NAc-ACC network). Furthermore, unlike female HCs, the female MDD group failed to show a significant increase of deactivation over stress exposure time in the amygdala, mOFC and NAc. Our findings confirm the importance of considering sex differences when investigating neural stress responses. Case-control differences in neural stress responses observed in females (but not males) provide insights into sex differences in the etiology and pathophysiology of depression. The failure to deactivate limbic/NAc regions in depressed females point to dysfunction of adaptive stress responses over stress exposure time.

Altered relationship between cortisol response to social stress and mediotemporal function during fear processing in people at clinical high risk for psychosis: a preliminary report

Evidence suggests that people at Clinical High Risk for Psychosis (CHR) have a blunted cortisol response to stress and altered mediotemporal activation during fear processing, which may be neuroendocrine-neuronal signatures of maladaptive threat responses. However, whether these facets are associated with each other and how this relationship is affected by cannabidiol treatment is unknown. We examined the relationship between cortisol response to social stress and mediotemporal function during fear processing in healthy people and in CHR patients. In exploratory analyses, we investigated whether treatment with cannabidiol in CHR individuals could normalise any putative alterations in cortisol-mediotemporal coupling. 33 CHR patients were randomised to 600 mg cannabidiol or placebo treatment. Healthy controls (n = 19) did not receive any drug. Mediotemporal function was assessed using a fearful face-processing functional magnetic resonance imaging paradigm. Serum cortisol and anxiety were measured immediately following the Trier Social Stress Test. The relationship between cortisol and mediotemporal blood-oxygen-level-dependent haemodynamic response was investigated using linear regression. In healthy controls, there was a significant negative relationship between cortisol and parahippocampal activation (p = 0.023), such that the higher the cortisol levels induced by social stress, the lower the parahippocampal activation (greater deactivation) during fear processing. This relationship differed significantly between the control and placebo groups (p = 0.033), but not between the placebo and cannabidiol groups (p = 0.67). Our preliminary findings suggest that the parahippocampal response to fear processing may be associated with the neuroendocrine (cortisol) response to experimentally induced social stress, and that this relationship may be altered in patients at clinical high risk for psychosis.

Alpha frontal asymmetry underlies individual differences in reactivity to acute psychosocial stress in males

People vary in their responses to stress. The present study aimed to investigate whether and how alpha frontal asymmetry (AFA) measured in the resting state underlies the individual differences in psychological responses to acute psychosocial stress (e.g., increases in heart rate and cortisol) induced by the Trier social stress test. Forty-three healthy male adults were enrolled in this study. The results showed that the AFA score negatively predicted both heart rate and cortisol responses, that is relatively higher right-frontal activity during the resting state was related to a stronger physiological stress response. These results indicated that higher withdrawal motivation or effortful control is associated with a higher physiological stress response, which suggested that AFA in the resting state can serve as a biological predictor of acute stress responses in men.

Functional brain network topology across the menstrual cycle is estradiol dependent and correlates with individual well-being

The menstrual cycle (MC) is a sex hormone‐related phenomenon that repeats itself cyclically during the woman's reproductive life. In this explorative study, we hypothesized that coordinated variations of multiple sex hormones may affect the large‐scale organization of the brain functional network and that, in turn, such changes might have psychological correlates, even in the absence of overt clinical signs of anxiety and/or depression. To test our hypothesis, we investigated longitudinally, across the MC, the relationship between the sex hormones and both brain network and psychological changes. We enrolled 24 naturally cycling women and, at the early‐follicular, peri‐ovulatory, and mid‐luteal phases of the MC, we performed: (a) sex hormone dosage, (b) magnetoencephalography recording to study the brain network topology, and (c) psychological questionnaires to quantify anxiety, depression, self‐esteem, and well‐being. We showed that during the peri‐ovulatory phase, in the alpha band, the leaf fraction and the tree hierarchy of the brain network were reduced, while the betweenness centrality (BC) of the right posterior cingulate gyrus (rPCG) was increased. Furthermore, the increase in BC was predicted by estradiol levels. Moreover, during the luteal phase, the variation of estradiol correlated positively with the variations of both the topological change and environmental mastery dimension of the well‐being test, which, in turn, was related to the increase in the BC of rPCG. Our results highlight the effects of sex hormones on the large‐scale brain network organization as well as on their possible relationship with the psychological state across the MC. Moreover, the fact that physiological changes in the brain topology occur throughout the MC has widespread implications for neuroimaging studies.

Maladaptive emotion regulation traits predict altered corticolimbic recovery from psychosocial stress

BACKGROUND

Adaptive recovery from stress promotes healthy cognitive affective functioning, whereas maladaptive recovery is linked to poor psychological outcomes. Neural regions, like the anterior cingulate and hippocampus, play critical roles in psychosocial stress responding and serve as hubs in the corticolimbic neural system. To date, however, it is unknown how cognitive emotion regulation traits (cER), adaptive and maladaptive, influence corticolimbic stress recovery. Here, we examined acute psychosocial stress neural recovery, accounting for cER.

METHODS

Functional neuroimaging data were collected while forty-seven healthy participants performed blocks of challenging, time-sensitive, mental calculations. Participants immediately received performance feedback (positive/negative/neutral) and their ranking, relative to fictitious peers. Participants rested for 90 seconds after each feedback, allowing for a neural stress recovery period. Collected before scanning, cER scores were correlated with neural activity during each recovery condition.

RESULTS

Negative feedback recovery yielded increased activity within the dorsomedial prefrontal cortex and amygdala, but this effect was ultimately explained by maladaptive cER (M-cER), like rumination. Isolating positive after-effects (i.e. positive > negative recovery) yielded a significant positive correlation between M-cER and the anterior cingulate, anterior insula, hippocampus, and striatum.

CONCLUSIONS

We provide first evidence of M-cER to predict altered neural recovery from positive stress within corticolimbic regions. Positive feedback may be potentially threatening to individuals with poor stress regulation. Identifying positive stress-induced activation patterns in corticolimbic neural networks linked to M-cER creates the possibility to identify these neural responses as risk factors for social-emotional dysregulation subsequent to rewarding social information, often witnessed in affective disorders, like depression.

Neural mechanisms of acute stress and trait anxiety in adolescents

Adolescence is a critical period of heightened stress sensitivity and elevated vulnerability for developing mental illness, suggesting a possible association between stress exposure and the etiology of psychiatric disorders. In adults, aberrant neurobiological responses to acute stress relate to anxiety symptoms, yet less is known about the neural stress response in adolescents and how it relates to biological and psychological variables. Here we characterize the neurobiology of stress response in adolescents using multiple modalities, including neuroimaging, subjective stress ratings, heart rate, and cortisol data. We evaluated stress response in adolescents using the Montreal Imaging Stress Task (MIST), an acute psychosocial stressor commonly administered in adult functional magnetic resonance imaging (fMRI) studies but not previously utilized with this population. FMRI data were acquired from 101 adolescents (44 female; 9-16 years) exhibiting varied trait anxiety severity. The MIST elicited decreased high-frequency heart rate variability and increased heart rate, subjective stress and cortisol. Whole-brain analyses comparing fMRI activity during experimental versus control MIST conditions revealed stress-related activation in regions including the anterior insula, dorsal anterior cingulate cortex, and dorsolateral prefrontal cortex and deactivations in the hippocampus, ventral striatum, and putamen. Region of Interest analyses found that during acute stress (a) hippocampal deactivation corresponded to heightened cortisol release, (b) trait anxiety was associated with increased hippocampal and ventral striatum activation and decreased putamen activity, and (c) males exhibited greater putamen deactivation than females. These results provide novel evidence that the MIST is an effective stressor for adolescents. Associations between the neural acute stress response, other biological factors, and trait anxiety highlight the importance of these neurobiological mechanisms in understanding anxiety disorders.

The functional connectome predicts feeling of stress on regular days and during the COVID-19 pandemic

Although many studies have explored the neural mechanism of the feeling of stress, to date, no effort has been made to establish a model capable of predicting the feeling of stress at the individual level using the resting-state functional connectome. Although individuals may be confronted with multidimensional stressors during the coronavirus disease 2019 (COVID-19) pandemic, their appraisal of the impact and severity of these events might vary. In this study, connectome-based predictive modeling (CPM) with leave-one-out cross-validation was conducted to predict individual perceived stress (PS) from whole-brain functional connectivity data from 817 participants. The results showed that the feeling of stress could be predicted by the interaction between the default model network and salience network, which are involved in emotion regulation and salience attribution, respectively. Key nodes that contributed to the prediction model comprised regions mainly located in the limbic systems and temporal lobe. Critically, the CPM model of PS based on regular days can be generalized to predict individual PS levels during the COVID-19 pandemic, which is a multidimensional, uncontrollable stressful situation. The stability of the results was demonstrated by two independent datasets. The present work not only expands existing knowledge regarding the neural mechanism of PS but also may help identify high-risk individuals in healthy populations.

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Perceived stress (PS) can be predicated by resting-state functional connectome.

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PS can be predicated by interaction between default model and salience network.

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Key nodes of the prediction model located in limbic systems and temporal lobe.

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psCPM of regular days generalized to predict PS level in the COVID-19 pandemic.

Violence exposure, affective style, and stress-induced changes in resting state functional connectivity

Chronic childhood stress is linked to greater susceptibility to internalizing disorders in adulthood. Specifically, chronic stress leads to changes in brain connectivity patterns, and, in turn, affects psychological functioning. Violence exposure, a chronic stressor, increases stress reactivity and disrupts emotion regulation processes. However, it is unclear to what extent violence exposure affects the neural circuitry underlying emotion regulation. Individual differences in affective style also moderate the impact of stress on psychological function and can thus alter the relationship between violence exposure and brain function. Resting-state functional connectivity (rsFC) is an index of intrinsic brain activity. Stress-induced changes in rsFC between the amygdala, hippocampus, and prefrontal cortex (PFC) are associated with emotion dysregulation and may elucidate how affective style modulates the relationship between violence exposure and brain connectivity. Therefore, the present study examined the impact of violence exposure and affective style on stress-induced changes in rsFC. Participants (n = 233) completed two 6-minute resting-state functional magnetic resonance imaging scans, one before (pre-stress) and one after (post-stress) a psychosocial stress task. The bilateral amygdala, hippocampus, and ventromedial prefrontal cortex (vmPFC) were used as seed regions for rsFC analyses. Significant stress-induced changes in the prefrontal, fronto-limbic, and parieto-limbic rsFC were observed. Further, pre-stress to post-stress differences in rsFC varied with violence exposure and affective style. These findings suggest that prefrontal, fronto-limbic, and parieto-limbic connectivity is associated with the emotional response to stress and provide new insight into the neural mechanisms through which affective style moderates the impact violence exposure has on the brain.

Associations between brain activity and endogenous and exogenous cortisol - A systematic review

To arrive at a coherent understanding of the relation between glucocorticoids and the human brain, we systematically reviewed the literature for studies examining the associations between endogenous or exogenous cortisol and human brain function. Higher levels of endogenous cortisol during psychological stress were related to increased activity in the middle temporal gyrus and perigenual anterior cingulate cortex (ACC), decreased activity in the ventromedial prefrontal cortex, and altered function (i.e., mixed findings, increased or decreased) in the amygdala, hippocampus and inferior frontal gyrus. Moreover, endogenous cortisol response to psychological stress was related to increased activity in the inferior temporal gyrus and altered function in the amygdala during emotional tasks that followed psychological stress. Exogenous cortisol administration was related to increased activity in the postcentral gyrus, superior frontal gyrus and ACC, and altered function in the amygdala and hippocampus during conditioning, emotional and reward-processing tasks after cortisol administration. These findings were in line with those from animal studies on amygdala activity during and after stress.

Increasing Deactivation of Limbic Structures Over Psychosocial Stress Exposure Time

BACKGROUND

Understanding the interplay between central nervous system and hypothalamic-pituitary-adrenal axis responses to stress in humans is assumed to be essential to contribute to the central question of stress research, namely how stress can increase disease risk. Therefore, the present study used a neuroimaging stress paradigm to investigate the interplay of 3 stress response domains. Furthermore, we asked if the brain's stress response changes over exposure time.

METHODS

In a functional magnetic resonance imaging study, changes in brain activation, cortisol levels, affect, and heart rate in response to an improved ScanSTRESS protocol were assessed in 67 young, healthy participants (31 females).

RESULTS

Stress exposure led to significant increases in cortisol levels, heart rate, and negative affect ratings as well as to activations and deactivations in (pre)limbic regions. When cortisol increase was used as a covariate, stronger responses in the hippocampus, amygdala, medial prefrontal cortex, and cingulate gyrus were observed. Responses within the same regions predicted negative affect ratings. Remarkably, an increasing deactivation over the two ScanSTRESS runs was found, again, in the same structures. A reanalysis of an independent sample confirmed this finding.

CONCLUSIONS

For the first time, reactions in a cluster of (pre)limbic structures was consistently found to be associated with changes in cortisol and negative affect. The same neural structures showed increasing deactivations over stress exposure time. We speculate that investigating possible associations between exposure-time effects in neural stress responses and stress-related interindividual differences (e.g., chronic stress) might be a promising new avenue in stress research.

Neural substrates for anticipation and consumption of social and monetary incentives in depression

Depression has been reliably associated with abnormalities in the neural representation of reward and loss. However, most studies have focused on monetary incentives; fewer studies have considered neural representation of social incentives. A direct comparison of non-social and social incentives within the same study would establish whether responses to the different incentives are differentially affected in depression. The functional magnetic resonance imaging study presented here investigated the neural activity of individuals with subthreshold depression (SD) and healthy controls (HCs) while they participated in an incentive delay task offering two types of reward (monetary gain vs social approval) and loss (monetary loss vs social disapproval). Compared to HCs, individuals with SD showed increased subgenual anterior cingulate cortex (sgACC) activity during anticipation of social loss, whereas the response in the putamen was decreased during consumption of social gain. Individuals with SD also exhibited diminished insula responses in consuming social loss. Furthermore, positive connectivity between the insula and ventral lateral pre-frontal cortex (VLPFC) was observed in individuals with SD while negative connectivity was found in HCs when consuming social loss. These results demonstrate neural alterations in individuals with depression, specific to the processing of social incentives, mainly characterised by dysfunction within the ‘social pain network’ (sgACC, insula and VLPFC).

Neuroticism modulates neural activities of posterior cingulate cortex and thalamus during psychosocial stress processing

OBJECTIVE

Individuals with higher neuroticism are vulnerable to stress and are prone to develop depression, however, the neural mechanisms underlying it have not been clarified clearly.

METHOD

The Montreal Imaging Stress Task (MIST) was administered to 148 healthy adults during functional magnetic resonance imaging (fMRI). Whole-brain voxel-wise regression analyses were used to detect associations of neuroticism with neural activity involved in perceiving and processing psychosocial stress. In addition, two-sample t-tests were conducted between the high-neurotic and low-neurotic group in order to supplement the results found in regression analyses.

RESULTS

Higher neuroticism scores were associated with higher activities in the posterior cingulate cortex (PCC)/precuneus and thalamus (p < 0.05, false discovery rate correction). Moreover, two sample t-tests also revealed that the high-neurotic group had higher neural stress responses in precuneus and bilateral thalamus in comparison to the low-neurotic group (p < 0.05, false discovery rate correction).

LIMITATIONS

Our study mainly recruited young adults, which may limit the generalizability of our findings.

CONCLUSIONS

Our findings highlight the crucial role of PCC/precuneus and thalamus in the association between neuroticism and stress and may provide insight into the cognitive model of depression.

Absence of default mode downregulation in response to a mild psychological stressor marks stress-vulnerability across diverse psychiatric disorders

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Maladaptation to acute stress constitutes an important vulnerability and maintenance factor for psychiatric disorders.

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We show transdiagnostic and disorder specific aspects of the brain's acute stress response.

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Our results mainly suggest shared, transdiagnostic aspects of a maladaptive stress response.

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Patients show relatively decreased frontoparietal network connectivity under stress.

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Absence of default mode network downregulation marks a maladaptive stress response across disorders.

Clinically, it is well-established that vulnerability to stress is a common feature across a broad spectrum of psychiatric disorders. However, this link has been mechanistically studied almost exclusively in patients with so-called stress-related disorders such as depression and anxiety. To probe transdiagnostic mechanisms, we set out to study the acute stress response across a broader range of psychiatric disorders taking a large-scale brain network perspective. We investigated the brain's response to a mild, experimentally well-controlled psychological stressor in the form of an aversive movie. We studied 168 patients with stress-related and/or neurodevelopmental disorders (including comorbidity) and 46 control subjects. We focused on three networks that have a central role in the brain's stress response and are affected in a wide range of psychiatric disorders: the salience network (SN), default mode network (DMN) and frontoparietal network (FPN). Our results support an increased vulnerability to stress across all patients, indicated by a higher subjective stress level at baseline and follow-up compared to matched controls. At the brain systems level, the stress response was characterized by a relatively decreased FPN connectivity and an absence of a decrease in the within DMN connectivity across all disorders compared to controls. At the neurocognitive level, these findings may reflect a diminished top-down control and a tendency to more pronounced (negative) self-referential processing. Besides these shared aspects of the maladaptive stress response, we also discuss indications for disorder-specific aspects. Taken together, our results emphasize the importance of investigating the mechanistic underpinnings of psychiatric disorders transdiagnostically as recently done in neurogenetics.

The creative thinking cognitive process influenced by acute stress in humans: an electroencephalography study

This study examined the underlying neural mechanism of acute stress affecting creative thinking. Twenty-six male participants underwent the Alternative Uses Test before and after acute stress test (Montreal Imaging Stress Task). Compared to before stress, stressed participants responded with higher salivary cortisol and salivary alpha-amylase. The electroencephalogram results indicated a general decrease in upper-frequency alpha power after stress, compared with that of before stress. The decrease in upper-frequency alpha power observed in the first stage after exposure to stress was related to memory and attention. Additionally, stress also reduced the differences between individuals with different creative abilities. In summary, these findings indicated that acute stress impaired creative thinking and primarily affected the earlier phase of the process of creative cognition. This study provides some practical implications for educational practice and corporate innovation in that a more relaxed environment promotes creative output. Lay Summary Acute stress impaired creative thinking performance and mainly affects the earlier phase of the process of creative cognition. Additionally, stress seems to reduce the differences between individuals with different creative abilities.

Acute psychosocial stress alters thalamic network centrality

Acute stress triggers a broad psychophysiological response that is adaptive if rapidly activated and terminated. While the brain controls the stress response, it is strongly affected by it. Previous research of stress effects on brain activation and connectivity has mainly focused on pre-defined brain regions or networks, potentially missing changes in the rest of the brain. We here investigated how both stress reactivity and stress recovery are reflected in whole-brain network topology and how changes in functional connectivity relate to other stress measures. Healthy young males (n = 67) completed the Trier Social Stress Test or a control task. From 60 min before until 105 min after stress onset, blocks of resting-state fMRI were acquired. Subjective, autonomic, and endocrine measures of the stress response were assessed throughout the experiment. Whole-brain network topology was quantified using Eigenvector centrality (EC) mapping, which detects central hubs of a network. Stress influenced subjective affect, autonomic activity, and endocrine measures. EC differences between groups as well as before and after stress exposure were found in the thalamus, due to widespread connectivity changes in the brain. Stress-driven EC increases in the thalamus were significantly correlated with subjective stress ratings and showed non-significant trends for a correlation with heart rate variability and saliva cortisol. Furthermore, increases in thalamic EC and in saliva cortisol persisted until 105 min after stress onset. We conclude that thalamic areas are central for information processing after stress exposure and may provide an interface for the stress response in the rest of the body and in the mind.

Neural response to stress and perceived stress differ in patients with left temporal lobe epilepsy

Patients with epilepsy are often able to predict seizure occurrence subsequent to an acute stress experience. However, neuroimaging investigations into the neural basis of this relationship or the potential influence of perceived life stress are limited. The current study assessed the relationship between perceived stress and the neurobehavioral response to stress in patients with left temporal lobe epilepsy (LTLE) and healthy controls (HCs) using heart rate, salivary cortisol level, and functional magnetic resonance imaging and compared these effects between HCs and LTLE. Matched on perceived stress levels, groups of 36 patients with LTLE and 36 HCs completed the Montreal Imaging Stress Task, with control and stress math task conditions. Among LTLEs, 27 reported that prior (acute) stress affected their seizures (LTLES+), while nine did not (LTLES-). The results revealed that increased perceived stress was associated with seizure frequency in LTLE. Further, cortisol secretion was greater in LTLE, but did not vary with perceived stress as observed in HCs. A linear mixed-effects analysis revealed that as perceived stress increased, activation in the hippocampal complex (parahippocampal gyrus and hippocampus) decreased during stressful math in the LTLES+, increased in HCs, but did not vary in the LTLES-. Task-based functional connectivity analyses revealed LTLE differences in hippocampal functional connectivity with sensory cortex specific to stressor modalities. We argue that the current study demonstrates an inhibitory hippocampal mechanism underlying differences in resilience to stress between HCs and LTLE, as well as LTLE patients who report stress as a precipitant of seizures.

Resting-state functional connectivity and inflexibility of daily emotions in major depression

BACKGROUND

Major Depressive Disorder (MDD) is characterized by aberrant resting-state functional connectivity (FC) in anterior cingulate regions (e.g., subgenual anterior cingulate [sgACC]) and by negative emotional functioning that is inflexible or resistant to change.

METHODS

MDD (N = 33) and control (CTL; N = 31) adults completed a resting-state scan, followed by a smartphone-based Experience Sampling Methodology (ESM) protocol surveying 10 positive and negative emotions 5 times per day for 21 days. We used multilevel modeling to assess moment-to-moment emotional inflexibility (i.e., strong temporal connections between emotions). We examined group differences in whole-brain FC analysis of bilateral sgACC, and then examined associations between emotional experiences and the extracted FC values within each group.

RESULTS

As predicted, MDDs had inflexibility in sadness and avoidance (p < .001, FDR-corrected p < .05), indicating that these emotional experiences persist in depression. MDDs showed weaker FC between the right sgACC and pregenual/dorsal anterior cingulate (pg/dACC) than did CTLs (FWE-corrected, voxelwise p = .01). Importantly, sgACC-pg/dACC FC predicted sadness inflexibility in both MDDs (p = .046) and CTLs (p = .033), suggesting that sgACC FC is associated with day-to-day negative emotions.

LIMITATIONS

Other maladaptive behaviors likely also affect the flexibility of negative emotions. We cannot generalize our finding of a positive relation between sgACC FC and inflexibility of sadness to individuals with more chronic depression or who have recovered from depression.

CONCLUSIONS

Our preliminary findings suggest that connections between portions of the ACC contribute to the persistence of negative emotions and are important in identifying a brain mechanism that may underlie the maintenance of sadness in daily life.

Psychosocial stress reactivity is associated with decreased whole-brain network efficiency and increased amygdala centrality

Cognitive and emotional functions are supported by the coordinated activity of a distributed network of brain regions. This coordinated activity may be disrupted by psychosocial stress, resulting in the dysfunction of cognitive and emotional processes. Graph theory is a mathematical approach to assess coordinated brain activity that can estimate the efficiency of information flow and determine the centrality of brain regions within a larger distributed neural network. However, limited research has applied graph-theory techniques to the study of stress. Advancing our understanding of the impact stress has on global brain networks may provide new insight into factors that influence individual differences in stress susceptibility. Therefore, the present study examined the brain connectivity of participants that completed the Montreal Imaging Stress Task (Goodman et al., 2016; Wheelock et al., 2016). Salivary cortisol, heart rate, skin conductance response, and self-reported stress served as indices of stress, and trait anxiety served as an index of participant's disposition toward negative affectivity. Psychosocial stress was associated with a decrease in the efficiency of the flow of information within the brain. Further, the centrality of brain regions that mediate emotion regulation processes (i.e., hippocampus, ventral prefrontal cortex, and cingulate cortex) decreased during stress exposure. Interestingly, individual differences in cortisol reactivity were negatively correlated with the efficiency of information flow within this network, whereas cortisol reactivity was positively correlated with the centrality of the amygdala within the network. These findings suggest that stress reduces the efficiency of information transfer and leaves the function of brain regions that regulate the stress response vulnerable to disruption. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Cognitively and socially induced stress affects postural control

Postural control is an adaptive process that can be affected by many aspects of human behavior, including emotional contexts. The main emotional contexts that affect postural control are postural threat and passive viewing of aversive or threatening images, both of which produce a reduction in postural sway. The aim of the present study was to assess whether similar stress-related changes in postural sway can be observed using stress induced by social evaluative threat (SET) while performing arithmetic tasks. Twelve young adults performed an arithmetic and a postural control task separately, concurrently, and concurrently with added time pressure in the arithmetic task. In the final condition, participants were given negative feedback about their performance in the arithmetic task and performed it again while being observed (SET condition). Results showed that stress increased linearly with task demand. Postural sway and reaction times were not affected by the first two conditions; however, when time pressure was introduced, reaction times became faster and sway amplitude increased. Finally, introduction of SET caused the predicted reduction in postural sway and an increase in reaction times relative to the time pressure condition. Our results suggest that stress induced using a combination of arithmetic tasks and social evaluative threat leads to systematic changes in postural control. The paradigm developed in the present study would be very useful in assessing interactions between cognition, stress, and postural control in the context of postural instability and falls in older adults.

Cardiovascular and autonomic reactivity to psychological stress: Neurophysiological substrates and links to cardiovascular disease

Psychologically stressful experiences evoke changes in cardiovascular physiology that may influence risk for cardiovascular disease (CVD). But what are the neural circuits and intermediate physiological pathways that link stressful experiences to cardiovascular changes that might in turn confer disease risk? This question is important because it has broader implications for our understanding of the neurophysiological pathways that link stressful and other psychological experiences to physical health. This review highlights selected findings from brain imaging studies of stressor-evoked cardiovascular reactivity and CVD risk. Converging evidence across these studies complements animal models and patient lesion studies to suggest that a network of cortical, limbic, and brainstem areas for central autonomic and physiological control are important for generating and regulating stressor-evoked cardiovascular reactivity via visceromotor and viscerosensory mechanisms. Emerging evidence further suggests that these brain areas may play a role in stress-related CVD risk, specifically by their involvement in mediating metabolically-dysregulated or extreme stressor-evoked cardiovascular reactions. Contextually, the research reviewed here offers an example of how brain imaging and health neuroscience methods can be integrated to address open and mechanistic questions about the neurophysiological pathways linking psychological stress and physical health.

Oxytocin and Interpersonal Relationships

The neuropeptide oxytocin (OT) has emerged as a potent modulator of diverse aspects of interpersonal relationships. OT appears to work in close interaction with several other neurotransmitter networks, including the dopaminergic reward circuit, and to be dependent on sex-specific hormonal influences. In this chapter, we focus on four main domains of OT and interpersonal relationships, including (1) the protective effect of OT on an individual's ability to withstand stress (i.e., stress buffering), (2) the effect of OT on emotion recognition and empathy, (3) OT's ability to enhance social synchrony and cooperation among individuals, and (4) the effect of OT on an individual's perception of social touch. We then illustrate the connection between OT and loneliness while grieving the loss of a loved one. We finish by discussing the clinical potential of OT, focusing on its potential role as an adjunct to psychotherapy, its enhancement through sex-specific hormonal influences, and the difficulties that present themselves when considering OT as a therapy. Overall, we argue that OT continues to hold strong therapeutic promise, but that it is strongly dependent on internal and external influences, for instance the patient's personal past experiences and interaction with the therapist, in order to provide the best possible therapy.

Social correlates of the dominance rank and long-term cortisol levels in adolescent and adult male rhesus macaques (Macaca mulatta)

A common pattern in dominance hierarchies is that some ranks result in higher levels of psychosocial stress than others. Such stress can lead to negative health outcomes, possibly through altered levels of stress hormones. The dominance rank-stress physiology relationship is known to vary between species; sometimes dominants show higher levels of glucocorticoid stress hormones, whereas in other cases subordinates show higher levels. It is less clear how this relationship varies between groups of different ages or cultures. In this study, we used long-term cortisol measurement methods to compare the effect of rank on cortisol levels in adult and adolescent male rhesus macaques. In the adult groups, subordinates had significantly higher cortisol levels. In the adolescents, no significant correlation between cortisol and status was found. Further analysis demonstrated that the adult hierarchy was stricter than that of the adolescents. Adult subordinates received extreme aggression more frequently than dominants, and this class of behavior was positively correlated with cortisol; by contrast, adolescents showed neither trend. Together, these findings provide evidence for a cortisol-rank relationship determined by social factors, namely, despotism of the group, and highlight the importance of group-specific social analysis when comparing or combining results obtained from different groups of animals.

Internalizing and externalizing traits predict changes in sleep efficiency in emerging adulthood: an actigraphy study

Research on psychopathology and experimental studies of sleep restriction support a relationship between sleep disruption and both internalizing and externalizing disorders. The objective of the current study was to extend this research by examining sleep, impulsivity, antisocial personality traits, and internalizing traits in a university sample. Three hundred and eighty six individuals (161 males) between the ages of 18 and 27 years (M = 18.59, SD = 0.98) wore actigraphs for 7 days and completed established measures of disorder-linked personality traits and sleep quality (i.e., Personality Assessment Inventory (PAI), Triarchic Psychopathy Measure, Barratt Impulsiveness Scale-11, and the Pittsburgh Sleep Quality Index). As expected, sleep measures and questionnaire scores fell within the normal range of values and sex differences in sleep and personality were consistent with previous research results. Similar to findings in predominantly male forensic psychiatric settings, higher levels of impulsivity predicted poorer subjective sleep quality in both women and men. Consistent with well-established associations between depression and sleep, higher levels of depression in both sexes predicted poorer subjective sleep quality. Bidirectional analyses showed that better sleep efficiency decreases depression. Finally, moderation analyses showed that gender does have a primary role in sleep efficiency and marginal effects were found. The observed relations between sleep and personality traits in a typical university sample add to converging evidence of the relationship between sleep and psychopathology and may inform our understanding of the development of psychopathology in young adulthood.

Effects of Lycium barbarum polysaccharides on oxidative stress in hyperlipidemic mice following chronic composite psychological stress intervention

Chronic composite psychological stress intervention is the accumulation of factors which may induce psychological stress, including food deprivation, water deprivation and swimming in cold water. Approximately 40% of cases of atherosclerosis are associated with chronic composite psychological stress. The aim of the present study was to explore the effects of Lycium barbarum polysaccharides (LBP) on blood lipid levels and oxidative stress in hyperlipidemic mice, following chronic composite psychological stress. A hyperlipidemic mouse model was generated, and the mice were subjected to chronic composite psychological stress and treated with LBP for 30 days. After 30 days the triglyceride (TG) and total cholesterol (TC) levels were measured in the serum, and the mRNA expression levels of cholesterol 7α‑hydroxylase (CYP7A1) were determined in the liver, in order to observe any changes to lipid metabolism. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were measured in the liver to evaluate the effects of LBP on oxidative stress. The blood serum levels of interleukin‑6 (IL‑6) and heat shock protein 70 (HSP‑70) were measured to evaluate the extent of the aortic inflammatory response, and to determine the protective effects of LBP. The levels of TG, TC, MDA and IL‑6 were significantly higher in the mice subjected to chronic composite psychological stress (HS), as compared with the mice treated with LBP alone (HL), or treated with LBP and subjected to stress (HLS). In addition, SOD and HSP‑70 levels, and the mRNA expression levels of CYP7A1 were significantly lower in the HS group, as compared with that in the HL and HLS groups. These results suggest that chronic composite psychological stress may promote the occurrence and development of atherosclerosis, by inducing the aortic inflammatory response and lipid peroxidation. Furthermore, treatment with LBP significantly inhibited oxidative stress and the aortic inflammatory response.

Oxytocin facilitates the sensation of social stress

Essentially all social species experience social stress which can be a catalyst for detriments in mental and physical health. The neuropeptide oxytocin (OXT) has been shown to produce anxiolytic and antistress effects, thereby qualifying the OXT system as a promising drug target in the treatment of stress-related disorders. However, recently it has been shown that OXT can have anxiogenic effects as well. In the present study, we used functional magnetic resonance imaging to scan the brains of 60 healthy men while they were exposed to social stress after they received either intranasal OXT (24 IU) or placebo treatment. Although OXT administration did not alter salivary cortisol levels as a surrogate marker of stress axis activity, our participants initially reported an increment in perceived social stress. This behavioral effect was paralleled on the neural level by increased activity in the precuneus and cingulate cortex. Taken together, our results support the hypothesis that OXT can induce a self-referential processing bias which facilitates the sensation of social stress in the absence of altered endocrine responses.