Is behavioral inhibition a risk factor for depression?

Explanatory and modifying factors of the association between sex and depression onset during adolescence: An exploratory study

BACKGROUND

The prevalence of Major Depressive Disorder (MDD) is twice as high in women as in men and this difference already emerges during adolescence. Because the mechanisms underlying this sex-difference remain poorly understood, we took a bottom-up approach to identify factors explaining the sex-MDD relationship.

METHODS

Data came from the TRacking Adolescents' Individual Lives Survey (TRAILS), a population study investigating youths' development from age 11 into adulthood. We assessed multiple baseline covariates (e.g., demographic, social and psychological) at ages 11-13 years and MDD onset at ages 19 and 25 years. In regression analyses, each covariate's role in the sex-MDD association as an effect modifier or confounder/explanatory variable was investigated. Replicability was evaluated in an independent sample.

RESULTS

The analyses identified no effect-modifiers. Baseline internalizing problems, behavioral inhibition, dizziness, comfort in classroom, physical complaints, attention problems, cooperation, self/effortful control, interpersonal life events and computer use partially explained the association between sex and MDD at age 19. The association between sex and MDD at age 25 was explained by largely the same variables, but also by shyness, acne, antisocial behavior, aggression, affection from peers and time spent shopping. The explanatory roles of internalizing problems, behavioral inhibition, negative events involving gossip/rumors and leisure-time spending (computer-use/shopping) were replicated.

LIMITATIONS

Potentially important baseline variables were not included or had low response rates. Gender roles or identification were not considered. Baseline MDD was not adjusted for.

CONCLUSION

The sex-MDD association is partially explained by sex differences in symptoms and vulnerability factors already present in early adolescence.

The link between adolescent girls' interpersonal emotion regulation with parents and peers and depressive symptoms: A real-time investigation

Adolescents often experience heightened socioemotional sensitivity warranting their use of regulatory strategies. Yet, little is known about how key socializing agents help regulate teens' negative emotions in daily life and implications for long-term adjustment. We examined adolescent girls' interpersonal emotion regulation (IER) with parents and peers in response to negative social interactions, defined as parent and peer involvement in the teen's enactment of emotion regulation strategies. We also tested associations between rates of daily parental and peer IER and depressive symptoms, concurrently and one year later. Adolescent girls (N = 112; Mage = 12.39) at temperamental risk for depressive disorders completed a 16-day ecological momentary assessment protocol measuring reactivity to negative social interactions, parental and peer IER, and current negative affect. Results indicated that adolescents used more adaptive strategies with peers and more maladaptive strategies with parents in daily life. Both parental and peer IER down-regulated negative affect, reflected by girls' decreased likelihood of experiencing continued negative affect. Higher proportions of parental adaptive IER predicted reduced depressive symptoms one year later. Findings suggest that both parents and peers effectively help adolescent girls down-regulate everyday negative emotions; however, parents may offer more enduring benefits for long-term adjustment.

Differences in microglia morphological profiles reflect divergent emotional temperaments: insights from a selective breeding model

Microglia play critical roles in healthy brain development and function, as well as the neuropathology underlying a range of brain diseases. Despite evidence for a role of microglia in affective regulation and mood disorders, little is known regarding how variation in microglia status relates to individual differences in emotionality. Using a selective breeding model, we have generated rat lines with unique temperamental phenotypes that reflect broad emotional traits: bred low responder rats (bLRs) are novelty-averse and model a passive coping style, whereas bred high responder rats (bHRs) are highly exploratory and model an active coping style. To identify a functional role of microglia in these phenotypes, we administered minocycline, an antibiotic with potent microglia inhibiting properties and observed shifts in forced swim, sucrose preference, and social interaction behaviors in bLRs. Using detailed anatomical analyses, we compared hippocampal microglia profiles of bHRs and bLRs and found that although the lines had similar numbers of microglia, selective breeding was associated with a shift in the morphological features of these cells. Specifically, microglia from bLRs were characterized by a hyper-ramified morphology, with longer processes and more complicated branching patterns than microglia from bHRs. This morphology is thought to reflect an early stage of microglia activation and suggests that bLR microglia are in a reactive state even when animals are not overtly challenged. Taken together, our results provide novel evidence linking variation in inborn temperament with differences in the baseline status of microglia and implicate a role for microglia in shaping enduring emotional characteristics.

Validity of the 15-item social inhibition questionnaire in outpatients receiving psychological or psychiatric treatment: The association between social inhibition and affective symptoms

OBJECTIVE

Social inhibition may promote symptoms of depression and anxiety in adults from an outpatient hospital population. The current work builds on a previously corroborated construct of social inhibition and examines the psychometric properties of this assessment tool and its predictive validity in the adult outpatient hospital population.

METHODS

A total of 350 adult outpatients receiving treatment at the department of Medical Psychology or Psychiatry completed measures of social inhibition and symptoms of anxiety (7-item Generalized Anxiety Disorder scale) and depression (9-item Patient Health Questionnaire). Factor analyses, reliability estimates, and regression analyses were used to replicate the robustness of the model of social inhibition, and the 15-item Social Inhibition Questionnaire (SIQ15).

RESULTS

In the current sample (N = 350; M_age = 45 years; 67.4% women), factor analyses confirmed the previously suggested three-factor model of social inhibition as measured by the SIQ15. The subscales of behavioral inhibition, interpersonal sensitivity and social withdrawal proved to be internally consistent (Cronbach's α between 0.87/0.95) and stable over time (test-retest reliability between r = 0.76/0.83). At baseline, interpersonal sensitivity and social withdrawal were associated with anxiety and depressive symptoms. At three months follow-up, only interpersonal sensitivity was related to depressive symptoms.

CONCLUSIONS

Social inhibition is associated with anxiety and depression at baseline and can be reliably assessed with the SIQ15 in an outpatient hospital population. The association of interpersonal sensitivity with depressive symptoms at three-month follow-up suggests an important aim for future research on the development of preventive methods for affective symptoms in socially inhibited outpatients.

Neural Responses to Social Reward Predict Depressive Symptoms in Adolescent Girls During the COVID-19 Pandemic

OBJECTIVE

Adolescent depression is increasing during the COVID-19 pandemic, possibly related to dramatic social changes. Individual-level factors that contribute to social functioning, such as temperament and neural reactivity to social feedback, may confer risk for or resilience against depressive symptoms during the pandemic.

METHODS

Ninety-three girls (12-17 years) oversampled for high shy/fearful temperament were recruited from a longitudinal study for a follow-up COVID-19 study. During the parent study (2016-2018), participants completed a functional magnetic resonance imaging task eliciting neural activity to performance-related social feedback. Depressive symptoms were assessed during the parent study and COVID-19 follow-up (April-May 2020). In 65 participants with complete data, we examined how interactions between temperament and neural activation to social reward or punishment in a socio-affective brain network predict depressive symptoms during COVID-19.

RESULTS

Depressive symptoms increased during COVID-19. Significant interactions between temperament and caudate, putamen, and insula activation to social reward were found. Girls high in shy/fearful temperament showed negative associations between neural activation to social reward and COVID-19 depressive symptoms, whereas girls lower in shy/fearful temperament showed positive associations.

CONCLUSIONS

Girls high in shy/fearful temperament with reduced neural activation to social reward may be less likely to engage socially, which could be detrimental during the pandemic when social interactions are limited. In contrast, girls lower in shy/fearful temperament with heightened neural reactivity to social reward may be highly motivated to engage socially, which could also be detrimental with limited social opportunities. In both cases, improving social connection during the pandemic may attenuate or prevent depressive symptoms.

The Habenula in the Link Between ADHD and Mood Disorder

Attention-deficit/hyperactivity disorder (ADHD) is a childhood-onset, neurodevelopmental disorder, whereas major depressive disorder (MDD) is a mood disorder that typically emerges in adulthood. Accumulating evidence suggests that these seemingly unrelated psychiatric disorders, whose symptoms even appear antithetical [e.g., psychomotor retardation in depression vs. hyperactivity (psychomotor acceleration) in ADHD], are in fact associated with each other. Thus, individuals with ADHD exhibit high comorbidity with MDD later in life. Moreover, genetic studies have shown substantial overlaps of susceptibility genes between ADHD and MDD. Here, we propose a novel and testable hypothesis that the habenula, the epithalamic brain region important for the regulation of monoamine transmission, may be involved in both ADHD and MDD. The hypothesis suggests that an initially hypoactive habenula during childhood in individuals with ADHD may undergo compensatory changes during development, priming the habenula to be hyperactive in response to stress exposure and thereby increasing vulnerability to MDD in adulthood. Moreover, we propose a new perspective on habenular deficits in psychiatric disorders that consider the habenula a neural substrate that could explain multiple psychiatric disorders.

Toddler dysregulated fear predicts continued risk for social anxiety symptoms in early adolescence

Identifying early risk factors for the development of social anxiety symptoms has important translational implications. Accurately identifying which children are at the highest risk is of critical importance, especially if we can identify risk early in development. We examined continued risk for social anxiety symptoms at the transition to adolescence in a community sample of children (n = 112) that had been observed for high fearfulness at age 2 and tracked for social anxiety symptoms from preschool through age 6. In our previous studies, we found that a pattern of dysregulated fear (DF), characterized by high fear in low threat contexts, predicted social anxiety symptoms at ages 3, 4, 5, and 6 years across two samples. In the current study, we re-evaluated these children at 11-13 years of age by using parent and child reports of social anxiety symptoms, parental monitoring, and peer relationship quality. The scores for DF uniquely predicted adolescents' social anxiety symptoms beyond the prediction that was made by more proximal measures of behavioral (e.g., kindergarten social withdrawal) and concurrent environmental risk factors (e.g., parental monitoring, peer relationships). Implications for early detection, prevention, and intervention are discussed.

Shyness and Adjustment in Early Childhood in Southeast China: The Moderating Role of Conflict Resolution Skills

The massive social change in urban China today has led to a decline in the adaptive implications of shyness for child adjustment, yet evidence of this trend in young children is limited. Moreover, the underlying mechanisms that help to explain the associations between shyness and maladjustment remains poorly understood. The primary goal of the present study was to explore the moderating role of conflict resolution skills in the links between shyness and socio-emotional and school adjustment among urban Chinese preschoolers. Data were collected from 360 children (44.4% girls, M_age = 4.72 years, SD = 0.63) in kindergartens using parent ratings, teacher ratings, and child interviews. The analyses indicated that the relations between shyness and adjustment were moderated by child conflict resolution skills, which served to buffer shy children from adjustment problems. The results were discussed in terms of the implications of conflict resolution skills for early adjustment of shy preschoolers in the Chinese context.

From scanners to cell phones: neural and real-world responses to social evaluation in adolescent girls

While expanded use of neuroimaging seemed promising to elucidate typical and atypical elements of social sensitivity, in many ways progress in this space has stalled. This is in part due to a disconnection between neurobiological measurements and behavior outside of the laboratory. The present study uses a developmentally salient fMRI computer task and novel ecological momentary assessment protocol to examine whether early adolescent females (n = 76; ages 11–13) with greater neural reactivity to social rejection actually report greater emotional reactivity following negative interactions with peers in daily life. As hypothesized, associations were found between reactivity to perceived social threat in daily life and neural activity in threat-related brain regions, including the left amygdala and bilateral insula, to peer rejection relative to a control condition. Additionally, daily life reactivity to perceived social threat was associated with functional connectivity between the left amygdala and dorsomedial prefrontal cortex during rejection feedback. Unexpectedly, daily life social threat reactivity was also related to heightened amygdala and insula activation to peer acceptance relative to a control condition. These findings may inform key brain–behavior associations supporting sensitivity to social evaluation in adolescence.

Modeling heritability of temperamental differences, stress reactivity, and risk for anxiety and depression: Relevance to research domain criteria (RDoC)

Animal models provide important tools to study biological and environmental factors that shape brain function and behavior. These models can be effectively leveraged by drawing on concepts from the National Institute of Mental Health Research Domain Criteria (RDoC) Initiative, which aims to delineate molecular pathways and neural circuits that underpin behavioral anomalies that transcend psychiatric conditions. To study factors that contribute to individual differences in emotionality and stress reactivity, our laboratory utilized Sprague-Dawley rats that were selectively bred for differences in novelty exploration. Selective breeding for low versus high locomotor response to novelty produced rat lines that differ in behavioral domains relevant to anxiety and depression, particularly the RDoC Negative Valence domains, including acute threat, potential threat, and loss. Bred Low Novelty Responder (LR) rats, relative to their High Responder (HR) counterparts, display high levels of behavioral inhibition, conditioned and unconditioned fear, avoidance, passive stress coping, anhedonia, and psychomotor retardation. The HR/LR traits are heritable, emerge in the first weeks of life, and appear to be driven by alterations in the developing amygdala and hippocampus. Epigenomic and transcriptomic profiling in the developing and adult HR/LR brain suggest that DNA methylation and microRNAs, as well as differences in monoaminergic transmission (dopamine and serotonin in particular), contribute to their distinct behavioral phenotypes. This work exemplifies ways that animal models such as the HR/LR rats can be effectively used to study neural and molecular factors driving emotional behavior, which may pave the way toward improved understanding the neurobiological mechanisms involved in emotional disorders.

Emotion Induced Monoamine Neuromodulator Release Affects Functional Neurological Disorders

Functional neurologic disorders (FNDs), also called conversion disorder (previously called hysteria), can show almost all the symptoms of other neurological diseases, including both physical (for example, seizure, weakness, fatigue) and psychological (for instance, depression, anxiety) symptoms. In spite of our general knowledge about emotional processes and developmental defects in the formation of these somatic symptoms, there is still no systemic and comprehensive research on the effects of emotional developmental variables in FND. Recently, both experimental and theoretical emotion studies have been greatly increased, such as prediction error, conceptual act model, basic emotional theory, and monoamine neuromodulator based three primary emotions. In addition, a large amount of evidence has confirmed the role of psychosocial adversity (such as stressful life events, interpersonal difficulties) as an important risk factor for FND. Here, we review recent advances about emotional stress on FND, and pay special attention to the effects of monoamine neuromodulators, such as how norepinephrine and serotonin affect behaviors. Then, we discuss the significance of these changes for FND, which may contribute to clarifying the pathogenesis of FND, and thus provide potential therapeutic drug targets or psychological intervention methods in the future.

Where it Hurts the Most: Peer Interactions on Social Media and in Person are Differentially Associated with Emotional Reactivity and Sustained Affect Among Adolescent Girls

Social media (SM) use has increasingly changed how adolescents interact with their peers, yet it remains unclear how peer interactions on social media differ from in-person peer interactions. The current study evaluated whether the context (social media or in-person) of adolescent girls' worst and best peer interactions influenced their emotional responses to peer interactions and sustained affect in everyday life. In this study, a total of 110 adolescent girls (11-13 years old; mean age = 12.28 years) completed ecological momentary assessment (EMA) for 16 days following an initial baseline visit. Participants reported their worst (i.e., most negative) and best (i.e., most positive) interactions with peers since the last prompt, the context in which it occurred (social media or in-person), emotional reactivity during the interaction, and momentary affect. Multilevel models indicated that negative peer interactions that occurred on social media were more likely to be associated with sustained negative affect, but not negative emotional reactivity during the interaction. Positive interactions on social media were more likely to be associated with both lower positive emotional reactivity and lower sustained positive affect. Findings indicate that peer interactions on social media may differentially impact girls' emotional reactivity and sustained affect, particularly for positive interactions with peers. Findings highlight that social media and in-person peer interactions may impact how girls experience and respond to positive and negative peer interactions, which may have implications for peer relationships and onset of psychopathology during this vulnerable period.

Evidence for inhibited temperament as a transdiagnostic factor across mood and psychotic disorders

BACKGROUND

The conceptualization of risk for psychiatric illness is moving from risk factors for specific psychiatric disorders to factors that confer risk for multiple disorders. One potential transdiagnostic risk factor is inhibited temperament, a trait characterized by a fearful or avoidant response to novelty. Inhibited temperament is an established risk factor for anxiety disorders, and evidence suggests inhibited temperament is elevated in schizophrenia, bipolar disorder, and major depressive disorder.

METHODS

In the current study, we tested the hypothesis that inhibited temperament is a transdiagnostic factor in 490 participants including individuals with schizophrenia (n=184), psychotic bipolar disorder (n=61), major depression disorder (n=53), or no disorders (n=192). Participants completed assessments of temperament, personality, clinical symptoms, cognition, and functioning. An ANOVA was used to test for group differences in inhibited temperament scores. Regressions were used to test whether inhibited temperament scores were associated with the current measures and whether the associations were similar across disorders.

RESULTS

Inhibited temperament was similarly elevated in all patient groups compared to controls. Inhibited temperament was similarly associated with anxiety, depression, negative affect, and quality of life across patient groups. Inhibited temperament was not associated with cognition or functional impairment.

LIMITATION

Although the inhibited temperament measure is commonly used, it is a retrospective self-report which may be susceptible to biases.

CONCLUSIONS

The current study provides evidence that inhibited temperament is a transdiagnostic factor impacting affective systems across mood and psychotic disorders. Inhibited patients may especially benefit from treatments that specifically target anxiety and depression.

Rejection Sensitivity Mediates the Relationship Between Social-Interpersonal Stressors and Depressive Symptoms in Military Context

BACKGROUND

Depression is pervasive in the military context and is likely to elicit lasting negative effects on health. Based on interpersonal models, social-interpersonal stressors are significantly associated with the development and maintenance of depression. However, little is known about the mechanisms by which these stressors increase the risk of depression in terms of social relationships. Rejection sensitivity, which refers to people who are sensitive to social rejection and tend to anxiously expect, readily perceive, and overreact to it, may play an underlying role in this process, as it is formed through social-interpersonal stressors and then aggravates further symptoms of depression.

OBJECTIVES

The current study aimed to examine the mediating effects on the relationship between social-interpersonal stressors and depressive symptoms in the military context.

METHODS

This study recruited 600 soldiers aged from 17 to 36 (M = 21.80; SD = 2.99; 100% males) with a cluster sampling method who completed Social-Interpersonal Stressors subscale, Rejection Sensitivity Questionnaire (RSQ), and Self-Rating Depression Scale (SDS). Mediation analyses examined the underlying mechanism between social-interpersonal stressors and depressive symptoms.

RESULTS

The results support the hypothesis and indicate that rejection sensitivity mediates the association between social-interpersonal stressors and depressive symptoms (B indirect = 0.02, p < 0.001, 95% CI= 0.005 to 0.044).

CONCLUSIONS

The findings suggest that interventions designed to desensitize individuals' high levels of rejection sensitivity may help to decrease their risk of depressive symptoms in the military environment. Rejection sensitivity is an important mechanism underpinning the development of depressive symptoms. Other theoretical and applied implications for prevention of depressive symptoms in the military context are discussed.

Extending the neurocircuitry of behavioural inhibition: a role for the bed nucleus of the stria terminalis in risk for anxiety disorders

Behavioural inhibition is a biologically based risk factor for anxiety disorders. Children with behavioural inhibition are shy, cautious and avoidant of new situations. Much research on behavioural inhibition has focused on the amygdala as an underlying neural substrate and has identified differences in amygdala function and volume; however, amygdala findings have yet to lead to meaningful interventions for prevention or treatment of anxiety disorders. The bed nucleus of the stria terminalis (BNST) is a prime candidate to be a neural substrate of behavioural inhibition, given current evidence of BNST function and development in human research and animal models. Children with behavioural inhibition have an increased startle response to safety cues and an increased cortisol response to social evaluative situations, both of which are mediated by the BNST. In rodents, activation of the BNST underlies contextual fear responses and responses to uncertain and sustained threat. Non-human primates with anxious temperament (the macaque equivalent of behavioural inhibition) have increased BNST activity to ambiguous social situations, and activity of the BNST in anxious temperament is significantly heritable. Importantly, the BNST is sexually dimorphic and continues to develop into adulthood, paralleling the development of anxiety disorders in humans. Together, these findings suggest that further investigation of the BNST in behavioural inhibition is necessary and may lead to new avenues for the prevention and treatment of anxiety disorders.

Childhood temperament is associated with distress, anxiety and reduced quality of life in schizophrenia spectrum disorders

Schizophrenia is conceptualized as a neurodevelopmental disorder and pre-morbid differences in social function and cognition have been well-established. Less is known about pre-morbid temperament and personality. Inhibited temperament-the predisposition to respond to novelty with wariness, fear, or caution-is a premorbid risk factor for anxiety, depression, and substance use but is understudied in schizophrenia. Participants were patients with schizophrenia spectrum disorders (n = 166) and healthy controls (n = 180). Patients completed measures of childhood inhibited temperament, clinical symptoms (anxiety, depression, PANSS factors), and quality of life. Patients had significantly higher levels of inhibited temperament relative to healthy controls. In patients with schizophrenia, higher inhibited temperament was significantly associated with co-morbid anxiety disorders, greater anxiety and depression symptoms, higher PANSS Distress scores, lower PANSS Excitement scores, and lower quality of life. The current findings replicate and extend previous research with a larger sample and are consistent with vulnerability in an affective path to psychosis. In schizophrenia, higher inhibited temperament was associated with a cluster of mood and anxiety symptoms. Inhibited temperament was not associated with psychosis symptoms. Patients with high inhibited temperament may especially benefit from treatments that specifically target anxiety and depression.

A computer-based avatar task designed to assess behavioral inhibition extends to behavioral avoidance but not cognitive avoidance

Avoidance is a common feature of post-traumatic stress disorder (PTSD) as well as anxiety and depressive disorders. Avoidance can be expressed behaviorally as well as cognitively. Most personality assessments for avoidance involve self-report inventories which are susceptible to biased responding. The avatar task (Myers et al., 2016a) was developed as an objective measure of behavioral inhibition (BI) which is defined as a tendency for avoidance of unfamiliar people and situations. The avatar task has been demonstrated to screen avoidant behaviors related to BI, PTSD, as well as harm avoidance (HA) as measured by the Tridimensional Personality Questionnaire (TPQ). In the current work, the avatar task was tested with cognitive as well as behavioral avoidance as measured by the cognitive-behavioral avoidance scale (CBAS; Ottenbreit & Dobson, 2004). The CBAS includes four subscales which measure behavioral social (BS) avoidance, behavioral non-social (BN) avoidance, cognitive social (CS) avoidance, and cognitive non-social (CN) avoidance. It was hypothesized that avatar scores would be significantly positively related to behavioral, but not cognitive, avoidance. In addition, it was also hypothesized that performance on the avatar task would be more related to social than non-social behavioral avoidance. Participants completed the avatar task, the HA scale of the TPQ and the CBAS. Pearson's product moment correlations revealed that avatar scores were significantly related to CBAS total scores as well as BS and BN scores, but not CS and CN scores. In addition, BS has a stronger relationship with avatar scores than BN avoidance which fits with the social aspects of the scenarios in the avatar task. A median split of the avatar scores produced a significant difference in scores on the behavioral but not the cognitive subscales. Overall, the current results supported the idea that the avatar task is measuring behavioral avoidance, specifically in social situations, rather than cognitive avoidance. Future work could adapt the avatar task to include scenarios similar to the cognitive items on the CBAS to create an objective measure of cognitive avoidance which may be relevant in measuring avoidance in depression and behavioral avoidance associated with PTSD as well as anxiety disorders.

Childhood behavioral inhibition is associated with impaired mentalizing in adolescence

Recent advances suggest that impairment in social cognition (SC) may play a role in the development of social anxiety (SA). However, very few studies have analyzed whether SA fosters poorer social-cognitive development as it leads to social avoidance. This study aimed to analyze whether retrospectively assessed behavioral inhibition (BI) (i.e., an early form of SA) in childhood is associated with a deficit in social cognition operationalized as impairment of mentalizing (MZ) in adolescence. A sample of 256 adolescents (range: 12-18 years; mean age: 14.7 years; SD = 1.7) from general population were assessed for MZ capacities and retrospective BI through self-report and interview measures. Results comparing three groups of adolescents with different levels of childhood BI (low, moderate or high) and controlling for concurrent SA and depression reveal that the higher the level of BI, the lower the level of MZ. These results were consistent for almost all mentalization measures, including when both extreme (i.e., high vs. low BI) and non-extreme (i.e., high vs. moderate BI) were compared in both self-report and interview measures and in both dimensions of MZ (i.e., MZ referred to others' and to own mental states). These findings support that childhood forms of SA are associated to deficit in SC in adolescence. A possible bi-directional relationship between SA and SC, and the role that it may play in the pathway to clinical SA are discussed.

Profiling coping strategies in male and female rats: Potential neurobehavioral markers of increased resilience to depressive symptoms

Coping strategies have been associated with differential stress responsivity, perhaps providing a valuable neurobiological marker for susceptibility to the emergence of depressogenic symptoms or vulnerability to other anxiety-related disorders. Rats profiled with a flexible coping phenotype, for example, exhibit increased neurobiological markers of emotional regulation compared to active and passive copers (Bardi et al., 2012; Lambert et al., 2014). In the current study, responses of male and female rats to prediction errors in a spatial foraging task (dry land maze; DLM) were examined after animals were exposed to chronic unpredictable stress (CUS). Brains were processed following the DLM training/assessment for fos-activation patterns and several measures of neuroplasticity in relevant areas. Behavioral responses observed during both the CUS and DLM phases of testing suggested that males and females employ different means of gathering information such as increased ambulatory exploration in males and rear responses in females. Fecal samples collected during baseline and following CUS swim exposure revealed higher corticosterone (CORT) in active copers, whereas flexible copers had higher dehydroepiandrosterone (DHEA) and DHEA/CORT ratios, both indications of enhanced emotional regulation. Focusing on the neural analysis, flexible copers exhibited fewer fos-immunoreactive cells in the basolateral amygdala and a trend toward lower activation in the insula while encountering the prediction error associated with the DLM probe trial. Coping profiles also differentially influenced markers of neuroplasticity; specifically, flexible copers exhibited higher levels nestin-immunoreactivity (ir). Further, less hippocampal glucocorticoid receptor-ir was observed in the flexible copers than the active and passive copers. In sum, flexible coping rats exhibited evidence of emotional resilience as indicated by several neurobiological measures; however, despite increased rates of depression and related symptoms reported in human females, sex effects weren't as pervasive as coping strategy profiles in the analysis of neurobiological markers employed in the current study.

Recruitment of orbitofrontal cortex during unpredictable threat among adults at risk for affective disorders

BACKGROUND

Mood and anxiety disorders are characterized by altered prefrontal-amygdala function and increased behavioral inhibition (BI) in response to potential threat. Whether these alterations constitute a vulnerability or a symptom of illness remains unclear. The medial orbitofrontal cortex (mOFC) is thought to play a central role in estimating probability and cost of threat, in turn informing selection of subsequent behaviors. To better understand the behavioral and neural processes that may be associated with risk for psychopathology, we used a virtual reality paradigm to examine behavioral and neural responses of psychiatrically healthy adults with familial history of affective disorders during anticipation of unpredictable threat.

METHODS

Twenty psychiatrically healthy adults with high familial risk for affective disorders and 20 low-risk matched controls underwent functional magnetic resonance imaging concurrent with a paradigm in which they explored virtual contexts associated with the threat of shock or safety from shock. Subjective anxiety ratings, skin conductance, exploratory behavior, and neural responses were examined for threat versus safe conditions.

RESULTS

High-risk adults evidenced greater right mOFC activation, as well as greater BI, compared to low-risk adults. There were no significant group differences in subjective ratings or autonomic responses. Individuals exhibiting greater activity in the right mOFC showed greater BI and decreased skin conductance response.

CONCLUSIONS

These results suggest that BI and mOFC recruitment during anticipation of aversive outcomes may reflect a vulnerability for affective disorders. However, such a response may also serve as a compensatory response, protecting these high-risk individuals from negative outcomes (i.e., increased physiological arousal). These results suggest that the OFC may play a central role in driving threat-related behaviors and thus may be a target for efforts aimed at early detection or prevention.

Annual Research Review: An expanded account of information-processing mechanisms in risk for child and adolescent anxiety and depression

BACKGROUND

Anxiety and depression occurring during childhood and adolescence are common and costly. While early-emerging anxiety and depression can arise through a complex interplay of 'distal' factors such as genetic and environmental influences, temperamental characteristics and brain circuitry, the more proximal mechanisms that transfer risks on symptoms are poorly delineated. Information-processing biases, which differentiate youth with and without anxiety and/or depression, could act as proximal mechanisms that mediate more distal risks on symptoms. This article reviews the literature on information-processing biases, their associations with anxiety and depression symptoms in youth and with other distal risk factors, to provide direction for further research.

METHODS

Based on strategic searches of the literature, we consider how youth with and without anxiety and/or depression vary in how they deploy attention to social-affective stimuli, discriminate between threat and safety cues, retain memories of negative events and appraise ambiguous information. We discuss how these information-processing biases are similarly or differentially expressed on anxiety and depression and whether these biases are linked to genetic and environmental factors, temperamental characteristics and patterns of brain circuitry functioning implicated in anxiety and depression.

FINDINGS

Biases in attention and appraisal characterise both youth anxiety and depression but with some differences in how these are expressed for each symptom type. Difficulties in threat-safety cue discrimination characterise anxiety and are understudied in depression, while biases in the retrieval of negative and overgeneral memories have been observed in depression but are understudied in anxiety. Information-processing biases have been studied in relation to some distal factors but not systematically, so relationships remain inconclusive.

CONCLUSIONS

Biases in attention, threat-safety cue discrimination, memory and appraisal may characterise anxiety and/or depression risk. We discuss future research directions that can more systematically test whether these biases act as proximal mechanisms that mediate other distal risk factors.

Parents' behavioral inhibition moderates association of preschoolers' BI with risk for age 9 anxiety disorders

BACKGROUND

Temperamental behavioral inhibition (BI) in children predicts later anxiety disorders. However, many children with BI do not develop anxiety disorders, suggesting the importance of identifying moderating factors. The current study examined whether parents' history of BI moderates the associations between preschoolers' BI and anxiety disorders at age 9.

METHODS

The sample was 392 children and their parents from the community. Child BI was measured at age 3 using observational (Laboratory Temperament Assessment Battery; Lab-TAB) and parent report (Behavior Inhibition Questionnaire; BIQ) measures. In addition, both parents reported on their own history of childhood BI using the Retrospective Measure of Behavioral Inhibition (RMBI). When the children were 9 years old, a parent and the child were interviewed using the Kiddie Schedule for the Affective Disorders and Schizophrenia - Present and Lifetime version (K-SADS-PL).

RESULTS

Parents' reports of their own BI moderated the associations of both observed and parent-reported child BI at age 3 with children's anxiety disorders at age 9. Among children whose parents reported having had higher childhood BI, those who exhibited high BI at age 3 were more likely to meet criteria for anxiety disorders at age 9.

LIMITATIONS

The major limitation is the use of a retrospective measure of parental BI.

CONCLUSIONS

These findings demonstrate that parents' histories of childhood BI moderate the association between their young children's BI and subsequent anxiety disorders. Thus, parental BI appears to identify a subgroup of BI children at particularly high risk for developing anxiety disorders by late childhood.

Child regulative temperament as a mediator of parenting in the development of depressive symptoms: a longitudinal study from early childhood to preadolescence

Child temperament as well as parenting behaviors have been linked to adolescent depression. Beyond their main effects, the interplay between these factors is of interest. For example, in an interactive model, a differential susceptibility of temperamental variants to parenting has been suggested. However, so far, the differential susceptibility hypothesis has mostly been studied with a focus on externalizing disorders. On the other hand, parenting may shape the child's temperament and vice versa in a transactional process. In a prospective, longitudinal at-risk sample (163 boys, 176 girls), we assessed emotional (easy-difficult) and regulative (self-control) temperament at ages 4.5, and 8 years, respectively, as well as parenting quality at age 4.5 years using the HOME inventory. Hierarchical linear regression analysis was used to investigate the prediction of depressive symptoms at age 11, measured by the Child Depression Inventory, including interaction terms between the temperament variable and parenting. We additionally tested whether parenting was mediated by child temperament. As previously reported, both self-control and parenting were longitudinally associated with preadolescent depressive symptoms. There were no interactive effects between temperament and parenting. However, the effects of parenting were partly mediated by self-control. Our data do not support a differential susceptibility of temperamental variants in the development of preadolescent depression. However, our results are in line with the assumption that parenting may shape young children's temperament, with positive parenting in the early childhood fostering the development of regulative temperament.

Overexpressing Corticotropin-Releasing Factor in the Primate Amygdala Increases Anxious Temperament and Alters Its Neural Circuit

BACKGROUND

Nonhuman primate models are critical for understanding mechanisms underlying human psychopathology. We established a nonhuman primate model of anxious temperament (AT) for studying the early-life risk to develop anxiety and depression. Studies have identified the central nucleus of the amygdala (Ce) as an essential component of AT's neural substrates. Corticotropin-releasing factor (CRF) is expressed in the Ce, has a role in stress, and is linked to psychopathology. Here, in young rhesus monkeys, we combined viral vector technology with assessments of anxiety and multimodal neuroimaging to understand the consequences of chronically increased CRF in the Ce region.

METHODS

Using real-time intraoperative magnetic resonance imaging-guided convection-enhanced delivery, five monkeys received bilateral dorsal amygdala Ce-region infusions of adeno-associated virus serotype 2 containing the CRF construct. Their cagemates served as unoperated control subjects. AT, regional brain metabolism, resting functional magnetic resonance imaging, and diffusion tensor imaging were assessed before and 2 months after viral infusions.

RESULTS

Dorsal amygdala CRF overexpression significantly increased AT and metabolism within the dorsal amygdala. Additionally, we observed changes in metabolism in other AT-related regions, as well as in measures of functional and structural connectivity.

CONCLUSIONS

This study provides a translational roadmap that is important for understanding human psychopathology by combining molecular manipulations used in rodents with behavioral phenotyping and multimodal neuroimaging measures used in humans. The results indicate that chronic CRF overexpression in primates not only increases AT but also affects metabolism and connectivity within components of AT's neural circuitry.

Behavioral inhibition

Over the past 25 years, our understanding of the risks conferred by "behavioral inhibition to the unfamiliar" (BI) has grown tremendously, yet many questions remain. BI represents the persistent tendency to show extreme reticence, fearfulness, or avoidance in novel situations or with unfamiliar people. Prospective studies of high-risk offspring, selected community children, and unselected epidemiologic samples converge to suggest that BI confers specific risk for social anxiety disorder in early and middle childhood and adolescence. Later outcomes are less clear, with some studies suggesting associations with depression or panic disorder. Studies that find broad associations between BI and anxiety proneness in general may be limited by the absence of information about parental psychopathology (an important potential confound associated with both BI and anxiety disorders in offspring). A critical area for further inquiry is the degree to which BI confers risk for social anxiety disorder in the absence of family history of anxiety disorders. Additionally, although progress has been made in identifying risk factors, protective factors, and treatments that may influence the course of BI and associated anxiety, more work is needed. Also, several exciting inroads have been made into the genetic and neurobiologic underpinnings of BI, and future studies promise greater elucidation of these areas. For now, the clinical take-home message is that preschool-age children presenting with extreme and persistent BI are at elevated risk for social anxiety disorder and possibly for other future disorders; preliminary evidence suggests that these children may be helped by early cognitive-behavioral intervention.

What factors contribute to the risk of depression in epilepsy?--Tasmanian Epilepsy Register Mood Study (TERMS)

OBJECTIVE

To model the factors associated with depression in a community sample of people with epilepsy. The factors investigated were derived from proposed risk factors for depression from patients with epilepsy, other chronic illness, and the general population.

METHODS

Multivariate analysis using general linear regression models of factors associated with depression in the Tasmanian Epilepsy Register Mood Study (TERMS), a cross-sectional community sample of 440 patients with epilepsy.

RESULTS

A model with acceptable fit was created that explained 66% of the variance of depression. Associated factors included in this model were neuroticism, physical functioning, social support, past history of depression, and stressful life events.

SIGNIFICANCE

In this cross-sectional study designed specifically to investigate depression in epilepsy, we showed that general risk factors for depression in other illness and in the general population are also important in patients with epilepsy, with little support for disease-related risk factors.

A neural substrate for behavioral inhibition in the risk for major depressive disorder

OBJECTIVE

Behavioral inhibition (BI) is an early developing trait associated with cautiousness and development of clinical depression and anxiety. Little is known about the neural basis of BI and its predictive importance concerning risk for internalizing disorders. We looked at functional connectivity of the default-mode network (DMN) and salience network (SN), given their respective roles in self-relational and threat processing, in the risk for internalizing disorders, with an emphasis on determining the functional significance of these networks for BI.

METHOD

We used functional magnetic resonance imaging to scan, during the resting state, children and adolescents 8 to 17 years of age who were either at high familial risk (HR; n = 16) or low familial risk (LR; n = 18) for developing clinical depression and/or anxiety. Whole-brain DMN and SN functional connectivity were estimated for each participant and compared across groups. We also compared the LR and HR groups on levels of BI and anxiety, and incorporated these data into follow-up neurobehavioral correlation analyses.

RESULTS

The HR group, relative to the LR group, showed significantly decreased DMN connectivity with the ventral striatum and bilateral sensorimotor cortices. Within the HR group, trait BI increased as DMN connectivity with the ventral striatum and sensorimotor cortex decreased. The HR and LR groups did not differ with respect to SN connectivity.

CONCLUSION

Our findings show, in the risk for internalizing disorders, a negative functional relation between brain regions supporting self-relational processes and reward prediction. These findings represent a potential neural substrate for behavioral inhibition in the risk for clinical depression and anxiety.

The nature of individual differences in inhibited temperament and risk for psychiatric disease: A review and meta-analysis

What makes us different from one another? Why does one person jump out of airplanes for fun while another prefers to stay home and read? Why are some babies born with a predisposition to become anxious? Questions about individual differences in temperament have engaged the minds of scientists, psychologists, and philosophers for centuries. Recent technological advances in neuroimaging and genetics provide an unprecedented opportunity to answer these questions. Here we review the literature on the neurobiology of one of the most basic individual differences-the tendency to approach or avoid novelty. This trait, called inhibited temperament, is innate, heritable, and observed across species. Importantly, inhibited temperament also confers risk for psychiatric disease. Here, we provide a comprehensive review of inhibited temperament, including neuroimaging and genetic studies in human and non-human primates. We conducted a meta-analysis of neuroimaging findings in inhibited humans that points to alterations in a fronto-limbic-basal ganglia circuit; these findings provide the basis of a model of inhibited temperament neurocircuitry. Lesion and neuroimaging studies in non-human primate models of inhibited temperament highlight roles for the amygdala, hippocampus, orbitofrontal cortex, and dorsal prefrontal cortex. Genetic studies highlight a role for genes that regulate neurotransmitter function, such as the serotonin transporter polymorphisms (5-HTTLPR), as well as genes that regulate stress response, such as corticotropin-releasing hormone (CRH). Together these studies provide a foundation of knowledge about the genetic and neural substrates of this most basic of temperament traits. Future studies using novel imaging methods and genetic approaches promise to expand upon these biological bases of inhibited temperament and inform our understanding of risk for psychiatric disease.

A translational neuroscience approach to understanding the development of social anxiety disorder and its pathophysiology

This review brings together recent research from molecular, neural circuit, animal model, and human studies to help understand the neurodevelopmental mechanisms underlying social anxiety disorder. Social anxiety disorder is common and debilitating, and it often leads to further psychopathology. Numerous studies have demonstrated that extremely behaviorally inhibited and temperamentally anxious young children are at marked risk of developing social anxiety disorder. Recent work in human and nonhuman primates has identified a distributed brain network that underlies early-life anxiety including the central nucleus of the amygdala, the anterior hippocampus, and the orbitofrontal cortex. Studies in nonhuman primates have demonstrated that alterations in this circuit are trait-like in that they are stable over time and across contexts. Notably, the components of this circuit are differentially influenced by heritable and environmental factors, and specific lesion studies have demonstrated a causal role for multiple components of the circuit. Molecular studies in rodents and primates point to disrupted neurodevelopmental and neuroplastic processes within critical components of the early-life dispositional anxiety neural circuit. The possibility of identifying an early-life at-risk phenotype, along with an understanding of its neurobiology, provides an unusual opportunity to conceptualize novel preventive intervention strategies aimed at reducing the suffering of anxious children and preventing them from developing further psychopathology.

Serotonin transporter gene × environment and risk of depression in community-treated epilepsy

OBJECTIVES

This study aimed to test whether a specific serotonin transporter (5HTT) gene polymorphism interacting with life stress increased the risk of depression in patients with epilepsy.

METHODS

The Tasmanian Epilepsy Register Mood Study (TERMS) used a cross-sectional study design of a community sample of patients with epilepsy previously recruited into the Tasmanian Epilepsy Register. It employed a mailed self-complete questionnaire and saliva DNA collection. Depression was assessed using the Center for Epidemiologic Studies Depression Scale. Environmental measures were selected to cover recent stressful events, epilepsy-related stress, current social support, and early life stress.

RESULTS

Of 820 eligible participants, 553 (67%) participants completed the study. Experience of at least one stressful life event was very common, with a significant association between depression and the stressful life events (F=26.2, df=3, p<0.001). There was no association between serotonin transporter genotype and level of depressive symptoms reported (F=0.421, df=2, p=0.7). There was no evidence of any adverse life experiences interacting with serotonin transporter genotype to moderate the risk of depression.

SIGNIFICANCE

The failure to demonstrate a main effect of genotype on depression or a gene × environment interaction differs from several studies of patients with other chronic diseases. However, it is consistent with larger general population studies.

Behavioral inhibition in rhesus monkeys (Macaca mulatta) is related to the airways response, but not immune measures, commonly associated with asthma

Behavioral inhibition reflects a disposition to react warily to novel situations, and has been associated with atopic diseases such as asthma. Retrospective work established the relationship between behavioral inhibition in rhesus monkeys (Macaca mulatta) and airway hyperresponsiveness, but not atopy, and the suggestion was made that behavioral inhibition might index components of asthma that are not immune-related. In the present study, we prospectively examined the relationship between behavioral inhibition and airway hyperresponsiveness, and whether hormonal and immune measures often associated with asthma were associated with behavioral inhibition and/or airway hyperresponsiveness. In a sample of 49 yearling rhesus monkeys (mean = 1.25 years, n = 24 behaviorally inhibited animals), we measured in vitro cytokine levels (IL-4, IL-10, IL-12, IFN-γ) in response to stimulation, as well as peripheral blood cell percentages, cortisol levels, and percentage of regulatory T-cells (CD3+CD4+CD25+FOXP3+). Airway reactivity was assessed using an inhaled methacholine challenge. Bronchoalveolar lavage was performed and the proportion of immune cells was determined. Behaviorally inhibited monkeys had airway hyperresponsiveness as indicated by the methacholine challenge (p = 0.031), confirming our earlier retrospective result. Airway hyperresponsiveness was also associated with lower lymphocyte percentages in lavage fluid and marginally lower plasma cortisol concentrations. However, none of the tested measures was significantly related to both behavioral inhibition and airway hyperresponsiveness, and so could not mediate their relationship. Airway hyperresponsiveness is common to atopic and non-atopic asthma and behavioral inhibition has been related to altered autonomic activity in other studies. Our results suggest that behavioral inhibition might index an autonomically mediated reactive airway phenotype, and that a variety of stimuli (including inflammation within lung tissue that is not specifically associated with behavioral inhibition) may trigger the airways response.

The preventative effects of a brief, early intervention for preschool-aged children at risk for internalising: follow-up into middle adolescence

BACKGROUND

  There are few evaluations of very early intervention for the prevention of internalising disorders and those that exist generally evaluate outcomes to a maximum of 12 months. The current study evaluated the very long term effects (11 years) of a brief internalising prevention program presented to parents of preschool aged children.

METHODS

  The original sample comprised 146 preschool-aged children who scored high on measures of inhibited temperament. Half of the parents were given a brief educational program (six-sessions) to assist them to help their children reduce anxiousness. Over 70% of the original sample (n = 103) was assessed for the current study, which occurred when the sample was approximately 15 years. They were assessed on current diagnoses of anxiety and depression, as well as symptoms of anxiety, depression, negative thoughts, and life interference.

RESULTS

  Compared with controls, girls whose parents had been through the early intervention program showed significantly fewer internalising disorders, maternally reported anxiety symptoms and self-reported life interference, and trends toward lower self-reported anxiety symptoms and self reported thoughts of loss and failure. Boys showed few differences.

CONCLUSIONS

  A brief early intervention program delivered to parents of preschool-aged children who are at risk for later internalising distress shows lasting benefits for girls into the high-risk period of middle adolescence. Given the low costs associated with this program, these results show promise for strong public health benefits.

Headache disorders in children and adolescents: their association with psychological, behavioral, and socio-environmental factors

OBJECTIVE

This cross-sectional study on a randomly drawn population sample of children and adolescents (n = 3399; aged 9 to 15) aimed at the assessment of patterns of associations between psychosocial variables and primary headache disorders like migraine (MIG) or tension-type headache. A headache-free group served as a control.

METHODS

Data on headache and psychological trait variables (eg, internalizing symptoms), behavioral factors (eg, physical activities), and socio-environmental factors (eg, life events) were gathered by questionnaire. Logistic regression analyses were conducted with headache types (MIG, tension-type, and non-classifiable headache) as dependent variables.

RESULTS

The pattern of correlations was largely congruent between the headache disorders. Associations were closest regarding maladaptive psychological traits (in particular internalizing symptoms with an odds ratio > 4 regarding MIG) compared with socio-environmental factors and particularly the behavioral factors. Unfavorable psychological traits and socio-environmental strains demonstrated distinctly stronger associations with MIG than tension-type headache and explained more variance in the occurrence of pediatric headache disorders than parental headache. Sex-specific analyses showed similarities as well as differences regarding the correlations, and in general, the associations were stronger in girls than boys.

CONCLUSIONS

A common path model as posited by several researchers in the field may explain the parallelism in biopsychosocial vulnerability regarding the different headache disorders.

Integrating etiological models of social anxiety and depression in youth: evidence for a cumulative interpersonal risk model

Models of social anxiety and depression in youth have been developed separately, and they contain similar etiological influences. Given the high comorbidity of social anxiety and depression, we examine whether the posited etiological constructs are a correlate of, or a risk factor for, social anxiety and/or depression at the symptom level and the diagnostic level. We find core risk factors of temperament, genetics, and parent psychopathology (i.e., depression and anxiety) are neither necessary nor sufficient for the development of social anxiety and/or depression. Instead, aspects of children's relationships with parents and/or peers either mediates (i.e., explains) or moderates (i.e., interacts with) these core risks being related to social anxiety and/or depression. We then examine various parent- and peer-related constructs contained in the separate models of social anxiety and depression (i.e., parent-child attachment, parenting, social skill deficits, peer acceptance and rejection, peer victimization, friendships, and loneliness). Throughout our review, we report evidence for a Cumulative Interpersonal Risk model that incorporates both core risk factors and specific interpersonal risk factors. Most studies fail to consider comorbidity, thus little is known about the specificity of these various constructs to depression and/or social anxiety. However, we identify shared, differential, and cumulative risks, correlates, consequences, and protective factors. We then put forth demonstrated pathways for the development of depression, social anxiety, and their comorbidity. Implications for understanding comorbidity are highlighted throughout, as are theoretical and research directions for developing and refining models of social anxiety, depression, and their comorbidity. Prevention and treatment implications are also noted.

Who should report abnormal behavior at preschool age? The case of behavioral inhibition

Children who are behaviorally "inhibited"-a condition at the extreme of the behavioral inhibition dimension-experience distress in uncertain social situations. Although parents and teachers are in the best position to detect this condition, they rarely agree. This study aims to analyze the agreement between parents and teachers and to examine the relations between ratings made by parents and teachers and assessments made by clinicians and researchers. Parents, teachers and clinicians rated the behavioral inhibition of 365 preschoolers. Seventy-three randomly selected participants were observed using an adaptation of the Behavioral Inhibition Paradigm. Parent-teacher correlations on 34 items and different clusters were, on average, r = .3. The degree of convergence between observational measures and ratings by parents and teachers was moderate-low and did not improve when considering only subsamples from the ends of the distributions. Discriminant analysis suggests that both parents and teachers tend to have a moderate-low ability to detect "inhibited" children.

An internalizing pathway to alcohol use and disorder

Research emanating from the field of developmental science indicates that initial risk factors for alcohol use and disorder can be evident in early childhood. One dominant developmental pathway connecting these initial risk factors with subsequent alcohol involvement focuses on the central role of disinhibited or externalizing behaviors. In the current paper, we delineate a second pathway that focuses on internalizing symptomatology. Several studies indicate that internalizing symptoms in early and middle childhood predict alcohol involvement in adolescence and young adulthood. We use a developmental psychopathology framework to describe a risk model that traces the potential developmental markers of this internalizing pathway and to consider the relation between the internalizing pathway and the more widely researched externalizing pathway. We outline the markers of risk in this pathway and conclude with a discussion of the implications of this model for prevention efforts and future research. In this manner, we strive for a translational goal, linking our existing understanding of internalizing processes and alcohol use and disorder with our efforts to develop effective prevention programs.

Behavioral inhibition is associated with airway hyperresponsiveness but not atopy in a monkey model of asthma

OBJECTIVE

To determine whether indicators of behavioral inhibition and cortisol responses to stressful situations, obtained in infancy, were associated with asthma-related measures (atopy and airway hyperresponsiveness [AHR]) approximately 2 years later.

METHODS

Measures reflecting inhibited temperament and cortisol response after a 25-hour separation from mother and relocation to a novel room were obtained for 21 rhesus monkeys (mean age, 109 days; range, 91-122 days). Inhibited temperament was measured by reduced emotionality and increased vigilance. Atopy and AHR were assessed after 2 years (age range, 19-35 months) using skin tests to common aeroallergens and inhaled methacholine challenge, respectively.

RESULTS

No associations were found between atopy and either behavioral inhibition or cortisol levels (p > .56). Low emotionality was associated with AHR (r = 0.47, p = .03), and a trend was found for blunted cortisol responsiveness and AHR (r = 0.42, p = .06).

CONCLUSIONS

Inhibited temperament and blunted cortisol responsiveness may be related to the development of AHR that is common to both nonatopic and atopic asthma phenotypes and may indicate risk for nonatopic asthma specifically.

Behavioral Inhibition as a Risk Factor for the Development of Childhood Anxiety Disorders: A Longitudinal Study

This longitudinal study examined the additive and interactive effects of behavioral inhibition and a wide range of other vulnerability factors in the development of anxiety problems in youths. A sample of 261 children, aged 5 to 8 years, 124 behaviorally inhibited and 137 control children, were followed during a 3-year period. Assessments took place on three occasions to measure children's level of behavioral inhibition, anxiety disorder symptoms, other psychopathological symptoms, and a number of other vulnerability factors such as insecure attachment, negative parenting styles, adverse life events, and parental anxiety. Results obtained with Structural Equation Modeling indicated that behavioral inhibition primarily acted as a specific risk factor for the development of social anxiety symptoms. Furthermore, the longitudinal model showed additive as well as interactive effects for various vulnerability factors on the development of anxiety symptoms. That is, main effects of anxious rearing and parental trait anxiety were found, whereas behavioral inhibition and attachment had an interactive effect on anxiety symptomatology. Moreover, behavioral inhibition itself was also influenced by some of the vulnerability factors. These results provide support for dynamic, multifactorial models for the etiology of child anxiety problems.

Can developmental changes in inhibition and peer relationships explain why depressive symptoms increase in early adolescence?

Why do depressive symptoms increase during adolescence? Because inhibition and poor peer relationships predict adolescents' depressive symptoms concurrently, we hypothesized that adolescents who cope with the stresses of this period by becoming increasingly inhibited may experience increasing depressive symptoms both directly and due to increased difficulty with peers. Longitudinal data from 904 participants, (52% female; 87% Caucasian, 5% Hispanic, 4% African-American, 4.6% other) from the NICHD Study of Early Child Care were examined when youth were in sixth and ninth grades. Path analyses revealed a direct effect of inhibition: Youth who became more inhibited reported increasing depressive symptoms. Indirect effects showed that they also experienced declines in friendship quality and popularity, which in turn led to increases in depressive symptoms. Findings suggest that increasing inhibition as an adaptation to the stresses of adolescence, and particularly its impact on popularity, is a risk factor for increases in depressive symptoms.

Childhood history of behavioral inhibition and comorbidity status in 256 adults with social phobia

BACKGROUND

Behavioral inhibition (BI), a heritable temperament, predisposes one to an increased risk of social phobia. Recent investigations have reported that BI may also be a precursor to anxiety as well as depressive and alcohol-related disorders, which are frequently comorbid with social phobia. In the present study, we explored the relationship between BI and psychiatric disorders in 256 adults with a primary diagnosis of social phobia.

METHODS

BI severity was retrospectively assessed with the Retrospective Self-Report of Inhibition (RSRI). The severity of social phobia and the presence of comorbid diagnoses were evaluated with the Liebowitz Social Anxiety Scale (LSAS) and the Mini-International Neuropsychiatric Interview, respectively.

RESULTS

The RSRI score was significantly and positively correlated with both the LSAS score and the occurrence of a major depressive disorder. No significant association was found with other anxiety and substance-related disorders.

LIMITATION

The assessment of BI was retrospective and self-reported.

CONCLUSION

A childhood history of BI was associated with an increased risk of depressive comorbidity in social phobia.

Prediction of preadolescent depressive symptoms from child temperament, maternal distress, and gender: results of a prospective, longitudinal study

OBJECTIVE

The delineation of developmental pathways to juvenile depressive symptoms is of major clinical interest because these are known to be predictive for adult mood disorders and for a range of other mental health problems. This study investigates the impact of child temperament and early maternal distress, both of which are known to influence children's emotional development, on preadolescent depression.

METHODS

In a prospective, longitudinal at-risk sample (163 boys, 178 girls), we assessed temperament at the age of 3 months and at 2 years, 4.5 years, and 8 years, respectively, and chronic maternal distress during infancy. Hierarchical linear regression analysis was used to investigate the prediction of depressive symptoms at the age of 11 years measured by the Child Depression Inventory. In addition, we controlled for psychosocial and obstetric perinatal risks and gender.

RESULTS

Psychosocial risks and self-control temperament made significant independent contributions to preadolescent depression, whereas fearful, difficult temperament and obstetric risks were unrelated to depressive outcome. Interestingly, a clear gender difference emerged with a significant prediction from maternal distress only in girls.

CONCLUSIONS

Our data extend previous findings of a concurrent association between regulative temperament and juvenile depression to a predictive view. Furthermore, the results point toward gender-specific pathways to preadolescent depression and support earlier findings indicating that subclinical maternal distress may exert as detrimental effects on child development as clinical depression.

Translational research to prevent internalizing problems early in childhood

This article discusses the importance of and one approach to translational research to prevent internalizing problems very early in life. The World Health Organisation (WHO) predicts that by 2,030 internalizing problems will be second only to HIV/AIDS in the international burden of disease. Internalizing problems affect one in every seven school age children, with negative impacts on peer relations, school engagement, and later mental health, adult relationships, and employment. There is persuasive evidence that intervention in the preschool years can have a cost-effective impact on general developmental outcomes, compared to later school or adult intervention. However, the development of early childhood prevention for internalizing problems is in its infancy. Two significant risk factors for child internalizing problems are temperamental inhibition (characterized by fearfulness and withdrawal) and overinvolved/protective parenting practices. Rapee et al. have conducted two randomized "efficacy" trials with inhibited preschoolers in which a parenting group intervention reduced internalizing disorders up to 3 years later. Translational "effectiveness" research is now underway at the population level, to determine the balance of benefits and harms of systematically screening preschoolers for inhibition and subsequent intervention for all those affected. This rigorous public health research, followed by effective dissemination, addresses gaps identified in the WHO Prevention of Mental Disorders report.

Anxiety disorders as a risk factor for subsequent depression

Abstract Introduction. Patients with comorbid depression and anxiety disorders have a higher suicide risk, increased social and vocational dysfunction and more severe and refractory illness. Methods. This paper reviews the studies examining the temporal relationship between onset of anxiety disorders and depression. Results. The highest rates of subsequent depression have been found in generalized anxiety disorder, followed by panic disorder and social anxiety disorder. The largest numbers of studies have been done on social anxiety disorder. Panic attacks, separation anxiety disorder and specific phobia also have an association with higher rates of subsequent depression in a limited number of studies. Conclusion. Further studies are needed to investigate whether treatment and treatment outcomes in anxiety disorders has an effect on the risk for developing subsequent depression.

Polymorphisms in the GAD2 gene-region are associated with susceptibility for unipolar depression and with a risk factor for anxiety disorders

Glutamate decarboxylase (GAD) is the rate limiting enzyme for conversion of glutamic acid to gamma-aminobutyric acid (GABA). The GAD 65 kDa isoform is encoded by the gene GAD2 and is mainly expressed in synaptic terminals. It serves as an apoenzyme, which shows enhanced availability in situations of stress, responding to short-term demands for GABA. We analyzed 18 single nucleotide polymorphisms (SNPs) in the GAD2-gene region for associations with psychiatric diagnosis and behavioral inhibition (BI) derived from the personality traits neuroticism and extraversion as defined by the Eysenck Personality Questionaire (EPQ). A total of 268 patients with anxiety disorder (AD), 541 with unipolar depression (MD), and 541 healthy controls were included. We observe associations for five tag-SNPs with BI in the AD- and control samples as well as two additional case-control associations in the MD-sample. The associated SNPs lie within a 16KB linkage disequilibrium-block, including putative 5' GAD2-promoter-elements as well as the 3' end of the gene MYO3A. Using open access mRNA-expression data, we could show that BI-associated SNPs appear to be associated with differences in MYO3A- but not GAD2 lymphoblastoid-mRNA expression levels. These results support earlier studies that suggest associations of polymorphisms within the GAD2 locus with anxiety and affective disorders. However, data from expression studies imply that these polymorphisms could tag functional effects on the neighboring gene MYO3A, which is also expressed in the brain, including the cingulate cortex and the amygdala.

Retrospective reports of behavioral inhibition and young adults' current symptoms of social anxiety, depression, and anxious arousal

The primary goal of this study was to investigate the specificity of the social versus nonsocial components of self-reported behavioral inhibition during childhood with young adults' current symptoms of anhedonic depression, social anxiety, and anxious arousal. As hypothesized, the social component of BI demonstrated some specificity for symptoms of social anxiety versus other internalizing disorders. Furthermore, results support the hypothesis that the relationship between BI and depressive symptoms is mediated by levels of social anxiety and anxious arousal.

A selective intervention program for inhibited preschool-aged children of parents with an anxiety disorder: effects on current anxiety disorders and temperament

OBJECTIVE

The current study evaluated the efficacy of early intervention for preschool-aged children selected on the basis of risk who also met diagnostic criteria for anxiety disorders.

METHOD

Seventy-one 3- to 4-year-old children were selected based on demonstrating high levels of inhibition and having a parent with a current anxiety disorder. They were randomly allocated to an eight-session parent intervention or waitlist.

RESULTS

At baseline, all of the children met criteria for one or more anxiety disorders. At 6-month follow-up, the intervention group showed a significantly greater reduction in anxiety disorders and less interference from their anxiety than the waitlist. In addition, children in the intervention condition showed greater reductions in parent and laboratory observed measures of behavioral inhibition.

CONCLUSIONS

The results suggest that a brief early intervention delivered through parents can reduce current anxiety and associated risk and may have the potential to alter the developmental trajectory of anxiety in a high-risk group of young children.