Early childhood temperament predicts substance use in young adults

A trans-diagnostic cognitive behavioural conceptualisation of the positive and negative roles of social media use in adolescents’ mental health and wellbeing

Whilst research into the association between social media and mental health is growing, clinical interest in the field has been dominated by a lack of theoretical integration and a focus on pathological patterns of use. Here we present a trans-diagnostic cognitive behavioural conceptualisation of the positive and negative roles of social media use in adolescence, with a focus on how it interacts with common mental health difficulties. Drawing on clinical experience and an integration of relevant theory/literature, the model proposes that particular patterns of social media use be judged as helpful/unhelpful to the extent that they help/hinder the adolescent from satisfying core needs, particularly those relating to acceptance and belonging. Furthermore, it introduces several key interacting processes, including purposeful/habitual modes of engagement, approach/avoidance behaviours, as well as the potential for social media to exacerbate/ameliorate cognitive biases. The purpose of the model is to act as an aide for therapists to collaboratively formulate the role of social media in young people’s lives, with a view to informing treatment, and ultimately, supporting the development of interventions to help young people use social media in the service of their needs and values.

Key learning aims

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Behavioral Inhibition in Childhood: European Portuguese Adaptation of an Observational Measure (Lab-TAB)

The assessment of behaviorally inhibited children is typically based on parent or teacher reports, but this approach has received criticisms, mainly for being prone to bias. Several researchers proposed the additional use of observational methods because they provide a direct and more objective description of the child's functioning in different contexts. The lack of a laboratory assessment of temperament for Portuguese children justifies the adaptation of some episodes of the Laboratory Temperament Assessment Battery (Lab-TAB) as an observational measure for behavioral inhibition. Method: In our study, we included 124 children aged between 3 and 9 years and their parents. The evaluation of child behavioral inhibition was made by parent report (Behavioral Inhibition Questionnaire) and through Lab-TAB episodes. Parental variables with potential influence on parents’ reports were also collected using the Social Interaction and Performance Anxiety and Avoidance Scale (SIPAAS) and the Parental Overprotection Measure (POM). Results and Discussion: The psychometric analyses provided evidence that Lab-TAB is a reliable instrument and can be incorporated in a multi-method approach to assess behavioral inhibition in studies involving Portuguese-speaking children. Moderate convergence between observational and parent report measures of behavioral inhibition was obtained. Mothers’ characteristics, as well as child age, seem to significantly affect differences between measures, being potential sources of bias in the assessment of child temperament.

Peer Victimization in Late Childhood Moderates the Relationship between Childhood Fear/Inhibition & Adolescent Externalizing Symptoms

OBJECTIVE

Studies of the association between early childhood low temperamental fearfulness or behavioral inhibition (BI) and later externalizing symptoms are few and results are inconsistent, despite research from outside the temperament field that has linked fearlessness with externalizing problems. There is also a large literature showing that peer victimization (PV) predicts externalizing symptoms. However, no prior studies have examined the joint effect of low temperamental fearfulness/BI and PV on externalizing psychopathology. The current study examined the main and joint effects of low temperamental fearfulness/BI and PV on broad internalizing and externalizing problems, as well as more narrow forms of externalizing psychopathology.

METHOD

Participants included 559 children (86.5% white, 54% male) assessed at ages 3, 6, 9, and 12. Temperamental fearfulness/BI was assessed using laboratory observations at age 3. PV was assessed via semi-structured interviews at ages 6 and 9. Finally, internalizing and externalizing psychopathology were each assessed at ages 3 and 12.

RESULTS

After accounting for sex, race, and age 3 symptomatology, the joint effect of low temperamental fearfulness/BI and PV predicted higher levels of externalizing problems overall and specific externalizing symptom domains, but not internalizing problems.

CONCLUSION

These results suggest that there is an association between low temperamental fearfulness/BI and later externalizing psychopathology, but that it depends on moderating factors such as PV.

Childhood temperament and its association with adult psychiatric disorders in a prospective cohort study

BACKGROUND

Childhood temperament and its component factors have previously been shown to be associated with depression and anxiety disorders in later life. Studies have also suggested possible links between childhood temperament and later psychosis.

AIMS

To investigate the association between childhood temperament and its individual component factors, measured at age 5, and later psychiatric disorders.

METHOD

Using a sample from a Finnish birth cohort (N = 1014), we used logistic regression models to examine associations between maternal reported childhood temperament at age 5, and later psychiatric diagnosis, ascertained through linkage with the Finnish Hospital Discharge Register (FHDR).

RESULTS

Individuals with a childhood temperament rated as difficult at age 5 had almost 5-times the odds of developing a psychotic disorder in adulthood compared to those with a temperament rated as average by their mothers (OR = 4.91, 95% CI = 1.51-15.91). The individual temperament factors of approach withdrawal, adaptability and quality of mood were each independently associated with later psychotic disorder while the factors of regularity and threshold were associated with increased risk for mood disorders.

CONCLUSIONS

This study reports association between early childhood temperament and risk for psychosis and suggests that early childhood temperament may be a good target for early intervention to reduce the risk of psychiatric disorders.

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.

Early childhood social reticence and neural response to peers in preadolescence predict social anxiety symptoms in midadolescence

BACKGROUND

Early childhood social reticence (SR) and preadolescent social anxiety (SA) symptoms increase the risk for more severe SA in later adolescence. Yet, not all at-risk youth develop more severe SA. The emergence of distinct patterns of neural response to socially evocative contexts during pivotal points in development may help explain this discontinuity. We tested the extent to which brain function during social interactions in preadolescence influenced the effects of SA and early childhood SR on predicting SA symptoms in midadolescence.

METHODS

Participants (N = 53) were assessed for SR from ages 2 to 7. At age 11, SA symptoms were assessed and brain function was measured using functional magnetic resonance imaging (fMRI) as participants anticipated social evaluation from purported peers with a reputation for being unpredictable, nice, and mean. At age 13, SA symptoms were re-assessed. Moderated-mediation models tested the extent to which early childhood SR, preadolescent SA, and preadolescent brain function predicted midadolescent SA.

RESULTS

In individuals with preadolescent SA, the presence of early childhood SR and SR-linked differences in brain activation predicted more severe SA in midadolescence. Specifically, in those who exhibited preadolescent SA, greater early childhood SR was associated with enhanced bilateral insula engagement while anticipating unpredictable-versus-nice social evaluation in preadolescence, and more severe SA in midadolescence.

CONCLUSIONS

SR-linked neural responses to socially evocative peer interactions may predict more severe SA symptoms in midadolescence among individuals with greater preadolescent SA symptoms and childhood SR. This same pattern of neural response may not be associated with more severe SA symptoms in youth with only one risk factor.

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.

Shyness Trajectories across the First Four Decades Predict Mental Health Outcomes

Although childhood shyness is presumed to predict mental health problems in adulthood, no prospective studies have examined these outcomes beyond emerging adulthood. As well, existing studies have been limited by retrospective and cross-sectional designs and/or have examined shyness as a dichotomous construct. The present prospective longitudinal study (N = 160; 55 males, 105 females) examined shyness trajectories from childhood to the fourth decade of life and mental health outcomes. Shyness was assessed using parent- and self-rated measures from childhood to adulthood, once every decade at ages 8, 12-16, 22-26, and 30-35. At age 30-35, participants completed a structured psychiatric interview and an experimental task examining attentional biases to facial emotions. We found 3 trajectories of shyness, including a low-stable trajectory (59.4%), an increasing shy trajectory from adolescence to adulthood (23.1%), and a decreasing shy trajectory from childhood to adulthood (17.5%). Relative to the low-stable trajectory, the increasing, but not the decreasing, trajectory was at higher risk for clinical social anxiety, mood, and substance-use disorders and was hypervigilant to angry faces. We found that the development of emotional problems in adulthood among the increasing shy trajectory might be explained in part by adverse peer and social influences during adolescence. Our findings suggest different pathways for early and later developing shyness and that not all shy children grow up to have psychiatric and emotional problems, nor do they all continue to be shy.

Opposed effects of hyperthymic and cyclothymic temperament in substance use disorder (heroin- or alcohol-dependent patients)

INTRODUCTION

In the last decade, the comprehension of affective temperaments has helped us to outline the boundaries of mood disorders, and to expand our knowledge of nosographic areas other than those of affectivity, even if affectivity is closely related to them. In the field of substance use disorders, the temperamental profile of heroin addicts and alcoholics has been discussed elsewhere, but no comparison has yet been made between these two patient populations. Such a comparison would help to shed light on the pathogenetic mechanisms that link temperament with substance abuse.

METHODS

63 Heroin Use Disorder (HUD) and 94 Alcohol Use Disorder (AUD) patients were compared with 130 healthy controls, with the aim of outlining affective temperament quantity and typology according to the formulation of Akiskal and Mallya.

RESULTS

Cyclothymic temperamental quantity differentiated - both at the univariate and multivariate levels - between patients who had various different types of Substance Use Disorder, largely irrespective of the principal substance of abuse (heroin or alcohol); irritable temperament quantity differentiated HUD patients from AUD patients. Hyperthymic temperament typology seemed to be more frequent in healthy controls at both univariate and multivariate levels.

LIMITATION

Cross-sectional study.

CONCLUSIONS

Our analyses suggest that cyclothymic temperament quantity could best correspond to the temperamental profile of Substance Use Disorder patients independently of principal substance of abuse (alcohol or heroin), and that irritable temperament quantity may differentiate HUD from AUD patients. Hyperthymic temperament typology seemed to be highly protective for HUD and, though a bit less, for AUD patients, and was a typical feature of healthy controls.

ALTERED TOPOGRAPHY OF INTRINSIC FUNCTIONAL CONNECTIVITY IN CHILDHOOD RISK FOR SOCIAL ANXIETY

BACKGROUND

Extreme shyness in childhood arising from behavioral inhibition (BI) is among the strongest risk factors for developing social anxiety. Although no imaging studies of intrinsic brain networks in children with BI have been reported, adults with a history of BI exhibit altered functioning of frontolimbic circuits and enhanced processing of salient, personally relevant information. BI in childhood may be marked by increased coupling of salience (insula) and default (ventromedial prefrontal cortex [vmPFC]) network hubs.

METHODS

We tested this potential relation in 42 children ages 9-12, oversampled for high BI. Participants provided resting-state functional magnetic resonance imaging. A novel topographical pattern analysis of salience network intrinsic functional connectivity was conducted, and the impact of salience-default coupling on the relation between BI and social anxiety symptoms was assessed via moderation analysis.

RESULTS

Children with high BI exhibit altered salience network topography, marked by reduced insula connectivity to dorsal anterior cingulate and increased insula connectivity to vmPFC. Whole-brain analyses revealed increased connectivity of salience, executive, and sensory networks with default network hubs in children higher in BI. Finally, the relation between insula-ventromedial prefrontal connectivity and social anxiety symptoms was strongest among the children highest in BI.

CONCLUSIONS

BI is associated with an increase in connectivity to default network hubs that may bias processing toward personally relevant information during development. These altered patterns of connectivity point to potential biomarkers of the neural profile of risk for anxiety in childhood.

Toddler temperament and prenatal exposure to lead and maternal depression

BACKGROUND

Temperament is a psychological construct that reflects both personality and an infant's reaction to social stimuli. It can be assessed early in life and is stable over time Temperament predicts many later life behaviors and illnesses, including impulsivity, emotional regulation and obesity. Early life exposure to neurotoxicants often results in developmental deficits in attention, social function, and IQ, but environmental predictors of infant temperament are largely unknown. We propose that prenatal exposure to both chemical and non-chemical environmental toxicants impacts the development of temperament, which can itself be used as a marker of risk for maladaptive neurobehavior in later life. In this study, we assessed associations among prenatal and early life exposure to lead, mercury, poverty, maternal depression and toddler temperament.

METHODS

A prospective cohort of women living in the Mexico City area were followed longitudinally beginning in the second trimester of pregnancy. Prenatal exposure to lead (blood, bone), mercury, and maternal depression were assessed repeatedly and the Toddler Temperament Scale (TTS) was completed when the child was 24 months old. The association between each measure of prenatal exposure and performance on individual TTS subscales was evaluated by multivariable linear regression. Latent profile analysis was used to classify subjects by TTS performance. Multinomial regression models were used to estimate the prospective association between prenatal exposures and TTS performance.

RESULTS

500 mother-child pairs completed the TTS and had complete data on exposures and covariates. Three latent profiles were identified and categorized as predominantly difficult, intermediate, or easy temperament. Prenatal exposure to maternal depression predicted increasing probability of difficult toddler temperament. Maternal bone lead, a marker of cumulative exposure, also predicted difficult temperament. Prenatal lead exposure modified this association, suggesting that joint exposure in pregnancy to both was most toxic.

CONCLUSIONS

Maternal depression predicts difficult temperament and concurrent prenatal exposure to maternal depression and lead predicts a more difficult temperament phenotype in 2 year olds. The role of temperament as an intermediate variable in the path from prenatal exposures to neurobehavioral deficits and other health effects deserves further study.

Behavioral inhibition in childhood predicts smaller hippocampal volume in adolescent offspring of parents with panic disorder

Behavioral inhibition (BI) is a genetically influenced behavioral profile seen in 15-20% of 2-year-old children. Children with BI are timid with people, objects and situations that are novel or unfamiliar, and are more reactive physiologically to these challenges as evidenced by higher heart rate, pupillary dilation, vocal cord tension and higher levels of cortisol. BI predisposes to the later development of anxiety, depression and substance abuse. Reduced hippocampal volumes have been observed in anxiety disorders, depression and posttraumatic stress disorder. Animal models have demonstrated that chronic stress can damage the hippocampal formation and implicated cortisol in these effects. We, therefore, hypothesized that the hippocampi of late adolescents who had been behaviorally inhibited as children would be smaller compared with those who had not been inhibited. Hippocampal volume was measured with high-resolution structural magnetic resonance imaging in 43 females and 40 males at 17 years of age who were determined to be BI+ or BI- based on behaviors observed in the laboratory as young children. BI in childhood predicted reduced hippocampal volumes in the adolescents who were offspring of parents with panic disorder, or panic disorder with comorbid major depression. We discuss genetic and environmental factors emanating from both child and parent that may explain these findings. To the best of our knowledge, this is the first study to demonstrate a relationship between the most extensively studied form of temperamentally based human trait anxiety, BI, and hippocampal structure. The reduction in hippocampal volume, as reported by us, suggests a role for the hippocampus in human trait anxiety and anxiety disorder that warrants further investigation.

Female adolescents with severe substance and conduct problems have substantially less brain gray matter volume

Objective

Structural neuroimaging studies have demonstrated lower regional gray matter volume in adolescents with severe substance and conduct problems. These research studies, including ours, have generally focused on male-only or mixed-sex samples of adolescents with conduct and/or substance problems. Here we compare gray matter volume between female adolescents with severe substance and conduct problems and female healthy controls of similar ages. Hypotheses: Female adolescents with severe substance and conduct problems will show significantly less gray matter volume in frontal regions critical to inhibition (i.e. dorsolateral prefrontal cortex and ventrolateral prefrontal cortex), conflict processing (i.e., anterior cingulate), valuation of expected outcomes (i.e., medial orbitofrontal cortex) and the dopamine reward system (i.e. striatum).

Methods

We conducted whole-brain voxel-based morphometric comparison of structural MR images of 22 patients (14-18 years) with severe substance and conduct problems and 21 controls of similar age using statistical parametric mapping (SPM) and voxel-based morphometric (VBM8) toolbox. We tested group differences in regional gray matter volume with analyses of covariance, adjusting for age and IQ at p<0.05, corrected for multiple comparisons at whole-brain cluster-level threshold.

Results

Female adolescents with severe substance and conduct problems compared to controls showed significantly less gray matter volume in right dorsolateral prefrontal cortex, left ventrolateral prefrontal cortex, medial orbitofrontal cortex, anterior cingulate, bilateral somatosensory cortex, left supramarginal gyrus, and bilateral angular gyrus. Considering the entire brain, patients had 9.5% less overall gray matter volume compared to controls.

Conclusions

Female adolescents with severe substance and conduct problems in comparison to similarly aged female healthy controls showed substantially lower gray matter volume in brain regions involved in inhibition, conflict processing, valuation of outcomes, decision-making, reward, risk-taking, and rule-breaking antisocial behavior.

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.

Behavioral Inhibition: Temperament or Prodrome?

Individual differences in temperament emerge in the first months of life. Some infants display a heightened sensitivity to novelty and uncertainty in the world around them, leading a subset to fearfully withdraw from the social environment. Extreme forms of this temperament, Behavioral Inhibition (BI), are associated with increased risk for social anxiety disorder. Indeed, the link is so strong that some suggest that BI is not simply a risk factor for anxiety, but rather a milder form of the disorder. The current overview describes the literature linking BI and anxiety, highlighting the unique biobehavioral profiles evident in each construct. It then highlights specific evidence that may help distinguish the form and function of BI and anxiety. Finally, we briefly discuss unresolved issues that may help inform future work aimed at improving our understanding of individual development and shape therapeutic interventions directed at specific mechanisms of disorder.

Gaining insight into adolescent vulnerability for social anxiety from developmental cognitive neuroscience

Social anxiety disorder (SAD) markedly impairs daily functioning. For adolescents, SAD can constrain typical development precisely when social experiences broaden, peers' opinions are highly salient, and social approval is actively sought. Individuals with extreme, impairing social anxiety fear evaluation from others, avoid social interactions, and interpret ambiguous social cues as threatening. Yet some degree of social anxiety can be normative and non-impairing. Furthermore, a temperament of behavioral inhibition increases risk for SAD for some, but not all adolescents with this temperament. One fruitful approach taken to understand the mechanisms of social anxiety has been to use neuroimaging to link affect and cognition with neural networks implicated in the neurodevelopmental social reorientation of adolescence. Although initial neuroimaging studies of adolescent SAD and risk for SAD underscored the role of fear-processing circuits (e.g., the amygdala and ventral prefrontal cortex), recent work has expanded these circuits to include reward-processing structures in the basal ganglia. A growing focus on reward-related neural circuitry holds promise for innovative translational research needed to differentiate impairing from normative social anxiety and for novel ways to treat adolescent SAD that focus on both social avoidance and social approach.

Structural and functional bases of inhibited temperament

Children born with an inhibited temperament are at heightened risk for developing anxiety, depression and substance use. Inhibited temperament is believed to have a biological basis; however, little is known about the structural brain basis of this vulnerability trait. Structural MRI scans were obtained from 84 (44 inhibited, 40 uninhibited) young adults. Given previous findings of amygdala hyperactivity in inhibited individuals, groups were compared on three measures of amygdala structure. To identify novel substrates of inhibited temperament, a whole brain analysis was performed. Functional activation and connectivity were examined across both groups. Inhibited adults had larger amygdala and caudate volume and larger volume predicted greater activation to neutral faces. In addition, larger amygdala volume predicted greater connectivity with subcortical and higher order visual structures. Larger caudate volume predicted greater connectivity with the basal ganglia, and less connectivity with primary visual and auditory cortex. We propose that larger volume in these salience detection regions may result in increased activation and enhanced connectivity in response to social stimuli. Given the strong link between inhibited temperament and risk for psychiatric illness, novel therapeutics that target these brain regions and related neural circuits have the potential to reduce rates of illness in vulnerable individuals.

DRD4 and striatal modulation of the link between childhood behavioral inhibition and adolescent anxiety

Behavioral inhibition (BI), a temperament characterized by vigilance to novelty, sensitivity to approach-withdrawal cues and social reticence in childhood, is associated with risk for anxiety in adolescence. Independent studies link reward hyper-responsivity to BI, adolescent anxiety and dopamine gene variants. This exploratory study extends these observations by examining the impact of DRD4 genotype and reward hyper-responsivity on the BI-anxiety link. Adolescents (N = 78) completed a monetary incentive delay task in the fMRI environment. Participants were characterized based on a continuous score of BI and the 7-repeat allele (7R+) of the DRD4 functional polymorphism. Parent-report and self-report measures of anxiety were also collected. Across the entire sample, striatal activation increased systematically with increases in the magnitude of anticipated monetary gains and losses. DRD4 status moderated the relation between BI and activation in the caudate nucleus. Childhood BI was associated with parent report of adolescent anxiety among 7R+ participants with elevated levels of striatal response to incentive cues. DRD4 genotype influenced the relations among neural response to incentives, early childhood BI and anxiety. The findings help refine our understanding of the role reward-related brain systems play in the emergence of anxiety in temperamentally at-risk individuals, building a foundation for future larger scale studies.