Neural correlates of three types of negative life events during angry face processing in adolescents

Neural correlates of negative life events and their relationships with alcohol and cannabis use initiation

OBJECTIVE

Negative life events (NLEs), e.g., poor academic performance (controllable) or being the victim of a crime (uncontrollable), can profoundly affect the trajectory of one's life. Yet, their impact on how the brain develops is still not well understood. This investigation examined the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) dataset for the impact of NLEs on the initiation of alcohol and cannabis use, as well as underlying neural mechanisms.

METHODS

This study evaluated the impact of controllable and uncontrollable NLEs on substance use initiation in 207 youth who initiated alcohol use, 168 who initiated cannabis use, and compared it to 128 youth who remained substance-naïve, using generalised linear regression models. Mediation analyses were conducted to determine neural pathways of NLE impacting substance use trajectories.

RESULTS

Dose-response relationships between controllable NLEs and substance use initiation were observed. Having one controllable NLE increased the odds of alcohol initiation by 50% (95%CI [1.18, 1.93]) and cannabis initiation by 73% (95%CI [1.36, 2.24]), respectively. Greater cortical thickness in left banks of the superior temporal sulcus mediated effects of controllable NLEs on alcohol and cannabis initiations. Greater left caudate gray-matter volumes mediated effects of controllable NLEs on cannabis initiation.

CONCLUSIONS

Controllable but not uncontrollable NLEs increased the odds of alcohol and cannabis initiation. Moreover, those individuals with less mature brain structures at the time of the NLEs experienced a greater impact of NLEs on subsequent initiation of alcohol or cannabis use. Targeting youth experiencing controllable NLEs may help mitigate alcohol and cannabis initiation.

Trajectories of cortical structures associated with stress across adolescence: a bivariate latent change score approach

BACKGROUND

Stress exposure in childhood and adolescence has been linked to reductions in cortical structures and cognitive functioning. However, to date, most of these studies have been cross-sectional, limiting the ability to make long-term inferences, given that most cortical structures continue to develop through adolescence.

METHODS

Here, we used a subset of the IMAGEN population cohort sample (N = 502; assessment ages: 14, 19, and 22 years; mean age: 21.945 years; SD = 0.610) to understand longitudinally the long-term interrelations between stress, cortical development, and cognitive functioning. To these ends, we first used a latent change score model to examine four bivariate relations - assessing individual differences in change in the relations between adolescent stress exposure and volume, surface area, and cortical thickness of cortical structures, as well as cognitive outcomes. Second, we probed for indirect neurocognitive effects linking stress to cortical brain structures and cognitive functions using rich longitudinal mediation modeling.

RESULTS

Latent change score modeling showed that greater baseline adolescence stress at age 14 predicted a small reduction in the right anterior cingulate volume (Std. β = -.327, p = .042, 95% CI [-0.643, -0.012]) and right anterior cingulate surface area (Std. β = -.274, p = .038, 95% CI [-0.533, -0.015]) across ages 14-22. These effects were very modest in nature and became nonsignificant after correcting for multiple comparisons. Our longitudinal analyses found no evidence of indirect effects in the two neurocognitive pathways linking adolescent stress to brain and cognitive outcomes.

CONCLUSION

Findings shed light on the impact of stress on brain reductions, particularly in the prefrontal cortex that have consistently been implicated in the previous cross-sectional studies. However, the magnitude of effects observed in our study is smaller than that has been reported in past cross-sectional work. This suggests that the potential impact of stress during adolescence on brain structures may likely be more modest than previously noted.

Electrophysiological evidence for sensitization effects elicited by concurrent social threats

Experiencing a social threat, such as social exclusion, is a painful event. In contrast to previous studies providing insight into the processing of a single short-termed threat, we exposed healthy individuals to the simultaneous onset of different social threats. This approach allowed us to track whether these threats are processed independently-or whether they interact in a common system. Using a virtual ball-throwing game (Cyberball), electrophysiological (event-related brain potentials, ERPs) and behavioral (self-reports) responses were collected. We assigned undergraduates to three experimental groups: single threat exclusion (n = 24), single threat loss of control (n = 26), and joint onset of both threats (dual-threat, n = 25). Self-reports indicated an increase in threats (i.e., in perceived exclusion and loss-of-control) in the latter group. The ERPs disentangled the neural responses to each threat: In the dual-threat group, the amplitudes of the P3 responses to exclusionary and intervention events were enhanced. This indicates that individuals are sensitized to each of the threats when the other threat is present simultaneously. Our findings support the theoretical notion of a common cognitive system responding to violations in subjective expectations.

Chronic stress in peer relationships moderates the association between pubertal development and neural response to emotional faces in adolescence

Adolescence is a period of heightened risk for multiple forms of psychopathology, partly due to greater exposure to interpersonal stress. One way that interpersonal stress may increase risk for psychopathology is by altering the normative development of neural systems that support socio-affective processing. The late positive potential (LPP) is an event-related potential component that reflects sustained attention to motivationally-salient information and is a promising marker of risk for stress-related psychopathology. However, it is not clear how the LPP to socio-affective information changes across adolescence, nor whether exposure to stress with peers interferes with normative developmental differences in the LPP to socio-affective content during this period. In 92 adolescent girls (10-19 years old), we assessed the LPP to task-irrelevant emotional and neutral faces, as well as behavioural measures of interference following the presentation of these faces. Adolescents at more advanced stages of puberty showed a smaller LPP to emotional faces, but adolescents exposed to greater peer stress exhibited a larger LPP to these stimuli. Additionally, for girls exposed to lower levels of peer stress, more advanced pubertal development was associated with a smaller LPP to emotional faces, whereas for girls exposed to higher levels of peer stress, the association between pubertal development and the LPP to emotional faces was not significant. Neither stress nor pubertal stage was significantly associated with behavioural measures. Combined, these data suggest that one pathway through which stress exposure increases risk for psychopathology during adolescence is by interfering with the normative development of socio-affective processing.

The eBRAIN study: The impact of early adversity on trajectories of brain maturation and mental health in young adolescents - A prospective cohort study

Introduction

More than 1 in 10 people are thought to experience a mental health problem during adolescence, with most adult psychopathology beginning during this time. Experiences of stress or adversity during childhood are important risk factors for poorer mental health outcomes and are also associated with alterations in neurodevelopment. There is evidence to suggest that this relationship is mediated by inflammation and the immune system. The eBRAIN study (The Impact of Early Adversity on Trajectories of Brain Maturation and Mental Health in Young Adolescents) will assess how early life adversity might affect trajectories of brain development throughout adolescence, whether these neurobiological changes are associated with psychopathology, and if they can potentially be explained by an activation of the immune system.

Methods

A cohort of 220 adolescents between the ages of 11-14 will be recruited into this study. Each participant will complete three study visits, each one year apart, at the Institute of Psychiatry, Psychology and Neuroscience, King's College London, London (UK). At each study visit, they will be assessed with structural and functional MRI scans, biological sample collection as well as questionnaires and interviews to collect demographic information, assess experiences of adversity, and details of psychopathology. The study will also collect information about factors such as diet and nutrition, physical exercise, and cognition.

Ethics and dissemination

Ethical approval for this study has been received by King's College London Research Ethics Committee (REC reference: HR-18/19-9033). Findings from the study will be published in peer-reviewed journals and disseminated at national and international conferences. Patient and public involvement (PPI) is an important component of the study, 'Study Champions' recruited from participants, their parents and teachers at collaborating schools have been invited to take an active role in study governance and dissemination.

Associations between lifetime stress exposure and the error-related negativity (ERN) differ based on stressor characteristics and exposure timing in young adults

Life stress increases risk for multiple forms of psychopathology, in part by altering neural processes involved in performance monitoring. However, the ways in which these stress-cognition effects are influenced by the specific timing and types of life stressors experienced remains poorly understood. To address this gap, we examined how different social-psychological characteristics and developmental timing of stressors are related to the error-related negativity (ERN), a negative-going deflection in the event-related potential (ERP) waveform that is observed from 0 to 100 ms following error commission. A sample of 203 emerging adults performed an ERN-eliciting arrow flanker task and completed an interview-based measure of lifetime stress exposure. Adjusting for stress severity during other developmental periods, there was a small-to-medium effect of stress on performance monitoring, such that more severe total stress exposure, as well as more severe social-evaluative stress in particular, experienced during early adolescence significantly predicted an enhanced ERN. These results suggest that early adolescence may be a sensitive developmental period during which stress exposure may result in lasting adaptations to neural networks implicated in performance monitoring.

The relationship between early and recent life stress and emotional expression processing: A functional connectivity study

The aim of this study was to characterize neural activation during the processing of negative facial expressions in a non-clinical group of individuals characterized by two factors: the levels of stress experienced in early life and in adulthood. Two models of stress consequences were investigated: the match/mismatch and cumulative stress models. The match/mismatch model assumes that early adversities may promote optimal coping with similar events in the future through fostering the development of coping strategies. The cumulative stress model assumes that effects of stress are additive, regardless of the timing of the stressors. Previous studies suggested that stress can have both cumulative and match/mismatch effects on brain structure and functioning and, consequently, we hypothesized that effects on brain circuitry would be found for both models. We anticipated effects on the neural circuitry of structures engaged in face perception and emotional processing. Hence, the amygdala, fusiform face area, occipital face area, and posterior superior temporal sulcus were selected as seeds for seed-based functional connectivity analyses. The interaction between early and recent stress was related to alterations during the processing of emotional expressions mainly in to the cerebellum, middle temporal gyrus, and supramarginal gyrus. For cumulative stress levels, such alterations were observed in functional connectivity to the middle temporal gyrus, lateral occipital cortex, precuneus, precentral and postcentral gyri, anterior and posterior cingulate gyri, and Heschl's gyrus. This study adds to the growing body of literature suggesting that both the cumulative and the match/mismatch hypotheses are useful in explaining the effects of stress.

A novel beamformer-based imaging of phase-amplitude coupling (BIPAC) unveiling the inter-regional connectivity of emotional prosody processing in women with primary dysmenorrhea

Objective. Neural communication or the interactions of brain regions play a key role in the formation of functional neural networks. A type of neural communication can be measured in the form of phase-amplitude coupling (PAC), which is the coupling between the phase of low-frequency oscillations and the amplitude of high-frequency oscillations. This paper presents a beamformer-based imaging method, beamformer-based imaging of PAC (BIPAC), to quantify the strength of PAC between a seed region and other brain regions.Approach. A dipole is used to model the ensemble of neural activity within a group of nearby neurons and represents a mixture of multiple source components of cortical activity. From ensemble activity at each brain location, the source component with the strongest coupling to the seed activity is extracted, while unrelated components are suppressed to enhance the sensitivity of coupled-source estimation.Main results. In evaluations using simulation data sets, BIPAC proved advantageous with regard to estimation accuracy in source localization, orientation, and coupling strength. BIPAC was also applied to the analysis of magnetoencephalographic signals recorded from women with primary dysmenorrhea in an implicit emotional prosody experiment. In response to negative emotional prosody, auditory areas revealed strong PAC with the ventral auditory stream and occipitoparietal areas in the theta-gamma and alpha-gamma bands, which may respectively indicate the recruitment of auditory sensory memory and attention reorientation. Moreover, patients with more severe pain experience appeared to have stronger coupling between auditory areas and temporoparietal regions.Significance. Our findings indicate that the implicit processing of emotional prosody is altered by menstrual pain experience. The proposed BIPAC is feasible and applicable to imaging inter-regional connectivity based on cross-frequency coupling estimates. The experimental results also demonstrate that BIPAC is capable of revealing autonomous brain processing and neurodynamics, which are more subtle than active and attended task-driven processing.

The IMAGEN study: a decade of imaging genetics in adolescents

Imaging genetics offers the possibility of detecting associations between genotype and brain structure as well as function, with effect sizes potentially exceeding correlations between genotype and behavior. However, study results are often limited due to small sample sizes and methodological differences, thus reducing the reliability of findings. The IMAGEN cohort with 2000 young adolescents assessed from the age of 14 onwards tries to eliminate some of these limitations by offering a longitudinal approach and sufficient sample size for analyzing gene-environment interactions on brain structure and function. Here, we give a systematic review of IMAGEN publications since the start of the consortium. We then focus on the specific phenotype 'drug use' to illustrate the potential of the IMAGEN approach. We describe findings with respect to frontocortical, limbic and striatal brain volume, functional activation elicited by reward anticipation, behavioral inhibition, and affective faces, and their respective associations with drug intake. In addition to describing its strengths, we also discuss limitations of the IMAGEN study. Because of the longitudinal design and related attrition, analyses are underpowered for (epi-) genome-wide approaches due to the limited sample size. Estimating the generalizability of results requires replications in independent samples. However, such densely phenotyped longitudinal studies are still rare and alternative internal cross-validation methods (e.g., leave-one out, split-half) are also warranted. In conclusion, the IMAGEN cohort is a unique, very well characterized longitudinal sample, which helped to elucidate neurobiological mechanisms involved in complex behavior and offers the possibility to further disentangle genotype × phenotype interactions.

Normative range parenting and the developing brain: A scoping review and recommendations for future research

Studies of early adversity such as trauma, abuse, and neglect highlight the critical importance of quality caregiving in brain development and mental health. However, the impact of normative range variability in caregiving on such biobehavioral processes remains poorly understood. Thus, we lack an essential foundation for understanding broader, population-representative developmental mechanisms of risk and resilience. Here, we conduct a scoping review of the extant literature centered on the question, "Is variability in normative range parenting associated with variability in brain structure and function?" After removing duplicates and screening by title, abstract, and full-text, 23 records were included in a qualitative review. The most striking outcome of this review was not only how few studies have explored associations between brain development and normative range parenting, but also how little methodological consistency exists across published studies. In light of these limitations, we propose recommendations for future research on normative range parenting and brain development. In doing so, we hope to facilitate evidence-based research that will help inform policies and practices that yield optimal developmental trajectories and mental health as well as extend the literature on the neurodevelopmental impact of early life stress.

Population neuroimaging: generation of a comprehensive data resource within the ALSPAC pregnancy and birth cohort

Neuroimaging offers a valuable insight into human brain development by allowing in vivo assessment of structure, connectivity and function. Multimodal neuroimaging data have been obtained as part of three sub-studies within the Avon Longitudinal Study of Parents and Children, a prospective multigenerational pregnancy and birth cohort based in the United Kingdom. Brain imaging data were acquired when offspring were between 18 and 24 years of age, and included acquisition of structural, functional and magnetization transfer magnetic resonance, diffusion tensor, and magnetoencephalography imaging. This resource provides a unique opportunity to combine neuroimaging data with extensive phenotypic and genotypic measures from participants, their mothers, and fathers.

Neuroimaging predictors of onset and course of depression in childhood and adolescence: A systematic review of longitudinal studies

Major depressive disorder (MDD) often emerges during adolescence with detrimental effects on development as well as lifetime consequences. Identifying neurobiological markers that are associated with the onset or course of this disorder in childhood and adolescence is important for early recognition and intervention and, potentially, for the prevention of illness onset. In this systematic review, 68 longitudinal neuroimaging studies, from 34 unique samples, that examined the association of neuroimaging markers with onset or changes in paediatric depression published up to 1 February 2019 were examined. These studies employed different imaging modalities at baseline; structural magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), functional MRI (fMRI) or electroencephalography (EEG). Most consistent evidence across studies was found for blunted reward-related (striatal) activity (fMRI and EEG) as a potential biological marker for both MDD onset and course. With regard to structural brain measures, the results were highly inconsistent, likely caused by insufficient power to detect complex mediating effects of genetic and environmental factors in small sample sizes. Overall, there were a limited number of samples, and confounding factors such as sex and pubertal development were often not considered, whereas these factors are likely to be relevant especially in this age range.

Parenting style moderates the effects of exposure to natural disaster-related stress on the neural development of reactivity to threat and reward in children

Little is known about the effect of natural disasters on children's neural development. Additionally, despite evidence that stress and parenting may both influence the development of neural systems underlying reward and threat processing, few studies have brought together these areas of research. The current investigation examined the effect of parenting styles and hurricane-related stress on the development of neural reactivity to reward and threat in children. Approximately 8 months before and 9 months after Hurricane Sandy, 74 children experiencing high and low levels of hurricane-related stress completed tasks that elicited the reward positivity and error-related negativity, event-related potentials indexing sensitivity to reward and threat, respectively. At the post-Hurricane assessment, children completed a self-report questionnaire to measure promotion- and prevention-focused parenting styles. Among children exposed to high levels of hurricane-related stress, lower levels of promotion-focused, but not prevention-focused, parenting were associated with a reduced post-Sandy reward positivity. In addition, in children with high stress exposure, greater prevention-focused, but not promotion-focused, parenting was associated with a larger error-related negativity after Hurricane Sandy. These findings highlight the need to consider contextual variables such as parenting when examining how exposure to stress alters the development of neural reactivity to reward and threat in children.