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Summary: Background: Higher body mass index (BMI) in childhood is associated with lower academic achievement. Objective: To explore potential pathways linking childhood BMI with educational attainment. Methods: Using data from the Avon Longitudinal Study of Parents and Children prospective cohort study (N = 6949), we assessed the association between BMI z‐scores at 11.7 years and educational attainment at 16 (General Certificate of Secondary Education [GCSE] results). Depressive symptoms, externalizing behaviours, bullying and school enjoyment were considered as potential mediators. Mediators were examined individually and jointly using sequential causal mediation. Results: Higher BMI z‐scores were associated with lower GCSE scores (females β = −3.47 95% CI −5.54, −1.41 males β = −4.33 95% CI −6.73, −1.94). Together, bullying, externalizing symptoms, depressive symptoms and school enjoyment mediated 41.9% of this association in females, and 23.3% in males. In males, evidence for mediation was weak (confidence intervals for all indirect effects spanned the null). In both females and males, most of the mediation was driven by externalizing symptoms. Conclusions: The detrimental effect of higher BMI on educational attainment appears to be partly explained by externalizing behaviours, particularly in females. Interventions to support behavioural problems may help the academic achievement of children with a higher body weight. [ABSTRACT FROM AUTHOR]

An important finding in the cognitive effort literature has been that sensitivity to the costs of effort varies between individuals, suggesting that some people find effort more aversive than others. It has been suggested this may explain individual differences in other aspects of cognition; in particular that greater effort sensitivity may underlie some of the symptoms of conditions such as depression and schizophrenia. In this paper, we highlight a major problem with existing measures of cognitive effort that hampers this line of research, specifically the confounding of effort and difficulty. This means that behaviour thought to reveal effort costs could equally be explained by cognitive capacity, which influences the frequency of success and thereby the chance of obtaining reward. To address this shortcoming, we introduce a new test, the Number Switching Task (NST), specially designed such that difficulty will be unaffected by the effort manipulation and can easily be standardised across participants. In a large, online sample, we show that these criteria are met successfully and reproduce classic effort discounting results with the NST. We also demonstrate the use of Bayesian modelling with this task, producing behavioural parameters which can be associated with other measures, and report a preliminary association with the Need for Cognition scale. [ABSTRACT FROM AUTHOR]

Background: Anxiety and depression are leading causes of disability worldwide, yet individuals are often unable to access appropriate treatment. There is a need to develop effective interventions that can be delivered remotely. Previous research has suggested that emotional processing biases are a potential target for intervention, and these may be altered through brief training programs. Methods: We report two experimental medicine studies of emotional bias training in two samples: individuals from the general population (n = 522) and individuals currently taking antidepressants to treat anxiety or depression (n = 212). Participants, recruited online, completed four sessions of EBT from their own home. Mental health and cognitive functioning outcomes were assessed at baseline, immediately post-training, and at 2-week follow-up. Results: In both studies, our intervention successfully trained participants to perceive ambiguous social information more positively. This persisted at a 2-week follow-up. There was no clear evidence that this change in emotional processing transferred to improvements in symptoms in the primary analyses. However, in both studies, there was weak evidence for improved quality of life following EBT amongst individuals with more depressive symptoms at baseline. No clear evidence of transfer effects was observed for self-reported daily stress, anhedonia or depressive symptoms. Exploratory analyses suggested that younger participants reported greater treatment gains. Conclusions: These studies demonstrate the effectiveness of delivering a multi-session online training program to promote lasting cognitive changes. Given the inconsistent evidence for transfer effects, EBT requires further development before it can be considered as a treatment for anxiety and depression. [ABSTRACT FROM AUTHOR]

Developmental crisis is a construct that is central to many theories of psychosocial adult development, yet there is currently no validated psychometric measure of adult developmental crisis that can be used across adult age groups. To address this gap in the literature, we developed and validated an age-independent measure of adult developmental crisis for research and applied purposes, entitled the Developmental Crisis Questionnaire (DCQ-12). Exploratory and confirmatory factor analyses were conducted separately on different samples. A three-factor structure emerged as the best fit with the data: (1) Disconnection and Distress; (2) Lack of Clarity and Control and (3) Transition and Turning Point. The DCQ-12 showed predictive validity with measures of self-esteem, locus of control, authentic living, optimism, presence of and search for meaning, turning points and a related crisis measure. Four-week test–retest reliability ranged from 0.78 to 0.89 across subscales. As well as research uses, the DCQ-12 measure has potential application in practice, given that assessment of developmental crisis has relevance to professionals working in clinical and non-clinical roles to support and coach adults through periods of transition. [ABSTRACT FROM AUTHOR]

Regulation of emotions is generally associated exclusively with the brain. However, there is evidence that peripheral systems are also involved in mood, stress vulnerability vs. resilience, and emotion‐related memory encoding. Prevalence of stress and mood disorders such as major depression, bipolar disorder, and post‐traumatic stress disorder is increasing in our modern societies. Unfortunately, 30%–50% of individuals respond poorly to currently available treatments highlighting the need to further investigate emotion‐related biology to gain mechanistic insights that could lead to innovative therapies. Here, we provide an overview of inflammation‐related mechanisms involved in mood regulation and stress responses discovered using animal models. If clinical studies are available, we discuss translational value of these findings including limitations. Neuroimmune mechanisms of depression and maladaptive stress responses have been receiving increasing attention, and thus, the first part is centered on inflammation and dysregulation of brain and circulating cytokines in stress and mood disorders. Next, recent studies supporting a role for inflammation‐driven leakiness of the blood–brain and gut barriers in emotion regulation and mood are highlighted. Stress‐induced exacerbated inflammation fragilizes these barriers which become hyperpermeable through loss of integrity and altered biology. At the gut level, this could be associated with dysbiosis, an imbalance in microbial communities, and alteration of the gut–brain axis which is central to production of mood‐related neurotransmitter serotonin. Novel therapeutic approaches such as anti‐inflammatory drugs, the fast‐acting antidepressant ketamine, and probiotics could directly act on the mechanisms described here improving mood disorder‐associated symptomatology. Discovery of biomarkers has been a challenging quest in psychiatry, and we end by listing promising targets worth further investigation. [ABSTRACT FROM AUTHOR]

Graduating from higher education is characterized by a complex set of changes, including the transition into employment as well as residential changes and identity shifts. We explored how wellbeing and depressive symptoms are associated with retrospective appraisals of developmental crisis in the year after leaving university, and the impact of living with parents following graduation. Data were collected from graduates based in the UK over the course of the 12 months following completing an undergraduate degree, via a 3-phase longitudinal design. One-third of the sample reported experiencing a developmental crisis within the year following university. Those who reported a crisis scored significantly lower on measures of environmental mastery across all time points and higher on measures of depression. Those living with parents scored significantly lower on measures of self-acceptance and autonomy and higher on measures of depression. In light of these findings, we conclude that interventions and targeted support to help students manage the psychological challenges of life after university should be developed and implemented. [ABSTRACT FROM AUTHOR]

Background: Mood and anxiety disorders are ubiquitous but current treatment options are ineffective for many sufferers. Moreover, a number of promising pre-clinical interventions have failed to translate into clinical efficacy in humans. Improved treatments are unlikely without better animal–human translational pipelines. Here, we translate a rodent measure of negative affective bias into humans, exploring its relationship with (1) pathological mood and anxiety symptoms and (2) transient induced anxiety. Methods: Adult participants (age = 29 ± 11) who met criteria for mood or anxiety disorder symptomatology according to a face-to-face neuropsychiatric interview were included in the symptomatic group. Study 1 included N = 77 (47 = asymptomatic [female = 21]; 30 = symptomatic [female = 25]), study 2 included N = 47 asymptomatic participants (25 = female). Outcome measures were choice ratios, reaction times and parameters recovered from a computational model of reaction time – the drift diffusion model (DDM) – from a two-alternative-forced-choice task in which ambiguous and unambiguous auditory stimuli were paired with high and low rewards. Results: Both groups showed over 93% accuracy on unambiguous tones indicating intact discrimination, but symptomatic individuals demonstrated increased negative affective bias on ambiguous tones [proportion high reward = 0.42 (s.d. = 0.14)] relative to asymptomatic individuals [0.53 (s.d. = 0.17)] as well as a significantly reduced DDM drift rate. No significant effects were observed for the within-subjects anxiety-induction. Conclusions: Humans with pathological anxiety symptoms directly mimic rodents undergoing anxiogenic manipulation. The lack of sensitivity to transient anxiety suggests the paradigm might be more sensitive to clinically relevant symptoms. Our results establish a direct translational pipeline (and candidate therapeutics screen) from negative affective bias in rodents to pathological mood and anxiety symptoms in humans. [ABSTRACT FROM AUTHOR]

Crisis episodes have been most commonly associated with midlife, and correspondingly research on crisis after midlife is marked by its absence. Here, we report findings from a retrospective interview-based study of 21 adults about crises occurring between the ages of 60 and 69, in the first attempt to explore the holistic structure, process and experiential contents of later-life crisis. Basing our analysis on existing models of late-adult development, four key areas of later-life crisis were explored as follows: (1) life events and relationships, (2) self and identity, (3) motivation and goals and (4) cognition and affect. We were able to define a provisional common holistic process to later-life crisis episodes, shared by all participants, which included multiple loss-inducing stressful life events that provide a cumulative challenge to coping resources, a struggle with ego integrity, increased mortality awareness and the re-scaling of goals, activities and roles in ways that pertain to re-engagement, continuity or disengagement. Findings are discussed in relation to theories of adult development in later life, while strategies are proposed for future research on this understudied area. [ABSTRACT FROM AUTHOR]

Abstract: Serotonergic medications can mitigate the negative affective biases in disorders such as depression or anxiety, but the neural mechanism by which this occurs is largely unknown. In line with recent advances demonstrating that negative affective biases may be driven by specific medial prefrontal-amygdala circuitry, we asked whether serotonin manipulation can alter affective processing within a key dorsal medial prefrontal-amygdala circuit: the putative human homologue of the rodent prelimbic-amygdala circuit or ‘aversive amplification’ circuit. In a double-blind, placebo-controlled crossover pharmaco-fMRI design, subjects (N=19) performed a forced-choice face identification task with word distractors in an fMRI scanner over two separate sessions. On one session subjects received dietary depletion of the serotonin precursor tryptophan while on the other session they received a balanced placebo control diet. Results showed that dorsal medial prefrontal responding was elevated in response to fearful relative to happy faces under depletion but not placebo. This negative bias under depletion was accompanied by a corresponding increase in positive dorsal medial prefrontal-amygdala functional connectivity. We therefore conclude that serotonin depletion engages a prefrontal-amygdala circuit during the processing of fearful relative to happy face stimuli. This same ‘aversive amplification’ circuit is also engaged during anxiety induced by shock anticipation. As such, serotonergic projections may inhibit engagement of the ‘aversive amplification’ circuit and dysfunction in this projection may contribute to the negative affective bias in mood and anxiety disorders. These findings thus provide a promising explanation for the role of serotonin and serotonergic medications in the neurocircuitry of negative affective bias. [Copyright &y& Elsevier]

Serotonin is strongly implicated in the mammalian stress response, but surprisingly little is known about its mode of action. Recent data suggest that serotonin can inhibit aversive responding in humans, but this remains underspecified. In particular, data in rodents suggest that global serotonin depletion may specifically increase long-duration bed nucleus of the stria terminalis (BNST)-mediated aversive responses (ie, anxiety), but not short-duration BNST-independent responses (ie, fear). Here, we extend these findings to humans. In a balanced, placebo-controlled crossover design, healthy volunteers (n=20) received a controlled diet with and without the serotonin precursor tryptophan (acute tryptophan depletion; ATD). Aversive states were indexed by translational acoustic startle measures. Fear and anxiety were operationally defined as the increase in startle reactivity during short- and long-duration threat periods evoked by predictable shock (fear-potentiated startle) and by the context in which the shocks were administered (anxiety-potentiated startle), respectively. ATD significantly increased long-duration anxiety-potentiated startle but had no effect on short-duration fear-potentiated startle. These results suggest that serotonin depletion in humans selectively increases anxiety but not fear. Current translational frameworks support the proposition that ATD thus disinhibits dorsal raphé-originating serotonergic control of corticotropin-releasing hormone-mediated excitation of the BNST. This generates a candidate neuropharmacological mechanism by which depleted serotonin may increase response to sustained threats, alongside clear implications for our understanding of the manifestation and treatment of mood and anxiety disorders. [ABSTRACT FROM AUTHOR]

The majority of individuals who suffer an episode of depression go on to experience recurrences. We have proposed, based upon the observation that reducing serotonin via acute tryptophan depletion (ATD) is more likely to induce negative mood in recovered depressed individuals than never depressed individuals, that this may be because associations form between negative mood and reduced serotonin during an episode of depression (Robinson and Sahakian, Psychol Med 38:315–318, ). Such associations would mean that subsequent reductions in serotonin are more likely to provoke depressed mood and hence trigger an episode of depression. In this study, we tested this hypothesis by manipulating the mood state of healthy females undergoing ATD (or balanced placebo) on two separate testing sessions. On the first session, subjects received either negative or neutral mood induction, while on the second session all subjects received neutral mood induction. Our findings demonstrate significant ATD-induced negative mood exclusively on the second visit of subjects who received both ATD and negative mood induction procedure on their first visit. These findings may be explained by the formation of an association between the negative mood and reduced serotonin states during the first visit. As such, these findings provide preliminary support for the associative hypothesis of recurrence in depression. Such associations might therefore explain the discrepancy between the effects of ATD in recovered- and never-depressed individuals and may, in turn, explain why an episode of depression increases the risk of subsequent episodes. [ABSTRACT FROM AUTHOR]

Post-traumatic stress disorder (PTSD) and major depressive disorder (MDD) are psychiatric disorders that can present with overlapping symptoms and shared risk factors. However, the extent to which these disorders share common underlying neuropathological mechanisms remains unclear. To investigate the similarities and differences in task-evoked brain activation patterns between patients with PTSD and MDD. A coordinate-based meta-analysis was conducted across 35 PTSD studies (564 patients and 543 healthy controls) and 125 MDD studies (4049 patients and 4170 healthy controls) using anisotropic effect-size signed differential mapping software. Both PTSD and MDD patients exhibited increased neural activation in the bilateral inferior frontal gyrus. However, PTSD patients showed increased neural activation in the right insula, left supplementary motor area extending to median cingulate gyrus and superior frontal gyrus (SFG), and left fusiform gyrus, and decreased neural activation in the right posterior cingulate gyrus, right middle temporal gyrus, right paracentral lobule, and right inferior parietal gyrus relative to MDD patients. Our meta-analysis suggests that PTSD and MDD share some similar patterns of brain activation, but also have distinct neural signatures. These findings contribute to our understanding of the potential neuropathology underlying these disorders and may inform the development of more targeted and effective treatment and intervention strategies. Moreover, these results may provide useful neuroimaging targets for the differential diagnosis of MDD and PTSD. • A first meta-analysis to investigate the common and distinct neural activation patterns of patients with MDD and PTSD • Common and distinct neural activation patterns in patients with MDD and PTSD were found. • Potential neuroimaging targets for the diagnosis and differentiation of PTSD and MDD were found. [ABSTRACT FROM AUTHOR]

Objective: Affective biases may underlie many of the key symptoms of major depressive disorder, from anhedonia to altered cognitive performance. Understanding the cause of these biases is therefore critical in the quest for improved treatments. Depression is associated, for example, with a negative affective bias in reversal learning. However, despite the fact that reversal learning is associated with striatal response in healthy individuals and depressed individuals exhibit attenuated striatal function on multiple tasks, studies to date have not demonstrated striatal involvement in the negative bias in reversal learning in depression. In this study, the authors sought to determine whether this may be because reversal learning tasks conventionally used to study behavior examine reversals only on the basis of unexpected punishment and therefore do not adequately separate reward- and punishment-based behavior. Method: The authors used functional MRI to compare the hemodynamic response to a reversal learning task with mixed reward- and punishment-based reversal stages between individuals with unmedicated major depressive disorder (N=13) and healthy comparison subjects (N=14). Results: Impaired reward (but not punishment) reversal accuracy was found alongside attenuated anteroventral striatal response to unexpected reward in depression. Conclusions: Attenuated neurophysiological response of the anteroventral striatum may reflect dysfunction in circuits involving afferent projections from the orbitofrontal, limbic, and/or mesostriatal dopaminergic pathways, which conceivably may, together with the ventral striatum, underlie anhedonia in depression. Learning to appreciate and enjoy positive life experiences is critical for recovery from depression. This study pinpoints a neural target for such recovery. [ABSTRACT FROM AUTHOR]

Generalized anxiety disorder is characterized by disruptions in decision-making, including an enhanced aversion to uncertain outcomes (i.e., risk aversion), which is not specific to negative outcomes (i.e., no loss aversion). It is unknown if this uncertainty bias is a trait-like causal factor contributing to anxiety symptoms, or a state-like feature triggered by anxiety symptoms such as worry chains. Here, in-patients with Major Depression Disorder (MDD), with (N = 16) or without (N = 24) Generalized anxiety (GA) symptoms, and healthy controls (N = 23), completed an economic decision-making task before and after worry induction. They were asked to choose between a certain monetary payoff, and an uncertain gamble, allowing for estimation of risk and loss aversion through a computational prospect-theoretic model. There were no significant differences in risk and loss aversion between any of the three groups at baseline. After worry induction, patients with GA symptoms, compared to those without, showed increased risk aversion. This increase was modulated by the severity of anxiety symptoms. These findings suggest that decision-making disruptions in anxiety disorder may be driven by anxiety symptoms such as worry, rather than causing them. This could shape etiological models, motivate standardization of emotional state in research on decision-making in anxiety disorders, support treatment strategies primarily aimed at worry management, and could guide novel interventions focusing on uncertainty exposure across aversive and appetitive domains. [ABSTRACT FROM AUTHOR]