The cognitive and neurobiological effects of daily stress in adolescents

Better together: A systematic review of studies combining magnetic resonance imaging with ecological momentary assessment

Social neuroscientists often use magnetic resonance imaging (MRI) to understand the relationship between social experiences and their neural substrates. Although MRI is a powerful method, it has several limitations in the study of social experiences, first and foremost its low ecological validity. To address this limitation, researchers have conducted multimethod studies combining MRI with Ecological Momentary Assessment (EMA). However, there are no existing recommendations for best practices for conducting and reporting such studies. To address the absence of standards in the field, we conducted a systematic review of papers that combined the methods. A systematic search of peer-reviewed papers resulted in a pool of 11,558 articles. Inclusion criteria were studies in which participants completed (a) Structural or functional MRI and (b) an EMA protocol that included self-report. Seventy-one papers met inclusion criteria. The following review compares these studies based on several key parameters (e.g., sample size) with the aim of determining feasibility and current standards for design and reporting in the field. The review concludes with recommendations for future research. A special focus is given to the ways in which the two methods were combined analytically and suggestions for novel computational methods that could further advance the field of social neuroscience.

Attention-Dominated Cognitive Dysfunction May Be a Biological Marker for Distinguishing SA from SI in Adolescents: A Network Analysis Study Based on Adolescent Depression

Objective

Suicidal behavior is strongly correlated with depressive symptoms and the degree of suicidal ideation. Cognitive impairment may have varying degrees of influence on suicidal ideation (SI) and suicidal attempts (SA). The aim of this study was to identify the cognitive biomarkers that distinguish suicidal ideation from suicidal attempts in adolescents.

Methods

The cross-sectional sample comprised 54 adolescents with major depressive disorder (MDD) and 32 healthy controls (HC). The THINC-it was utilized to assess cognitive function of all the samples. Suicidal ideation was examined by the Positive and Negative Suicide Ideation Scale (PANSI). Based on the type of data, one-way ANOVA or Kruskal-Wallis was performed to investigate group differences. Bonferroni post-hoc analysis was employed for regulating type I error for pairwise comparisons. Network analysis was used to compare the networks associated with suicidal ideation, depression symptoms, and cognitive function between SA and SI.

Results

The depression symptoms (HAMD-17) (F=72.515, P<0.001) and suicidal ideation (PANSI) (F=267.952, P<0.001) in the SA were higher than those in the SI. Analysis of between-group differences showed SA performed worse in THINC-it, especially in "Spotter (SP)" (P=0.033), "Objective cognition score (OS)" (P=0.027) and "Composite score (CS)" (P=0.017). Compared with SI, network analysis revealed that SA had a unique network of cognitive function, depressive symptoms, and suicidal ideation. Nevertheless, both networks exhibit comparable performance concerning the node strength of cognitive function. Within their separate networks, the aspects of CS, OS, and SP have emerged as the three most crucial elements.

Conclusion

Adolescents with SI or SA exhibit a broad spectrum of cognitive impairments. Attention impairment can be beneficial in discerning between SI and SA. Future interventions for adolescent suicide can center on attention and the comprehensive cognitive ability that it represents.

Alcohol and stress exposure across the lifespan are key risk factors for Alzheimer's Disease and cognitive decline

Alzheimer's Disease and related dementias (ADRD) are an increasing threat to global health initiatives. Efforts to prevent the development of ADRD require understanding behaviors that increase and decrease risk of neurodegeneration and cognitive decline, in addition to uncovering the underlying biological mechanisms behind these effects. Stress exposure and alcohol consumption have both been associated with increased risk for ADRD in human populations. However, our ability to understand causal mechanisms of ADRD requires substantial preclinical research. In this review, we summarize existing human and animal research investigating the connections between lifetime stress and alcohol exposures and ADRD.

Dynamic functional connectivity changes associated with psychiatric traits and cognitive deficits in Cushing's disease

Cushing's disease is a rare neuroendocrine disorder with excessive endogenous cortisol, impaired cognition, and psychiatric symptoms. Evidence from resting-state fMRI revealed the abnormalities of static brain connectivity in patients with Cushing's disease (CD patients). However, it is unknown whether the CD patients' dynamic functional connectivity would be abnormal and whether the dynamic features are associated with deficits in cognition and psychopathological symptoms. Here, we evaluated 50 patients with Cushing's disease and 57 healthy participants by using resting-state fMRI and dynamic functional connectivity (dFNC) approach. We focused on the dynamic features of default mode network (DMN), salience network (SN), and central executive network (CEN) because these are binding sites for the cognitive-affective process, as well as vital in understanding the pathophysiology of psychiatric disorders. The dFNC was further clustered into four states by k-mean clustering. CD patients showed more dwell time in State 1 but less time in State 4. Intriguingly, group differences in dwell time in these two states can explain the cognitive deficits of CD patients. Moreover, the inter-network connections between DMN and SN and the engagement time in State 4 negatively correlated with anxiety and depression but positively correlated with cognitive performance. Finally, the classifier trained by the dynamic features of these networks successfully classified CD patients from healthy participants. Together, our study revealed the dynamic features of CD patients' brains and found their associations with impaired cognition and emotional symptoms, which may open new avenues for understanding the cognitive and affective deficits induced by Cushing's disease.

Impact of stress on excitatory and inhibitory markers of adolescent cognitive critical period plasticity

Adolescence is a time of significant neurocognitive development. Prolonged maturation of prefrontal cortex (PFC) through adolescence has been found to support improvements in executive function. Changes in excitatory and inhibitory mechanisms of critical period plasticity have been found to be present in the PFC through adolescence, suggesting that environment may have a greater effect on development during this time. Stress is one factor known to affect neurodevelopment increasing risk for psychopathology. However, less is known about how stress experienced during adolescence could affect adolescent-specific critical period plasticity mechanisms and cognitive outcomes. In this review, we synthesize findings from human and animal literatures looking at the experience of stress during adolescence on cognition and frontal excitatory and inhibitory neural activity. Studies indicate enhancing effects of acute stress on cognition and excitation within specific contexts, while chronic stress generally dampens excitatory and inhibitory processes and impairs cognition. We propose a model of how stress could affect frontal critical period plasticity, thus potentially altering neurodevelopmental trajectories that could lead to risk for psychopathology.

Dense Sampling Approaches for Psychiatry Research: Combining Scanners and Smartphones

Together, data from brain scanners and smartphones have sufficient coverage of biology, psychology, and environment to articulate between-person differences in the interplay within and across biological, psychological, and environmental systems thought to underlie psychopathology. An important next step is to develop frameworks that combine these two modalities in ways that leverage their coverage across layers of human experience to have maximum impact on our understanding and treatment of psychopathology. We review literature published in the last 3 years highlighting how scanners and smartphones have been combined to date, outline and discuss the strengths and weaknesses of existing approaches, and sketch a network science framework heretofore underrepresented in work combining scanners and smartphones that can push forward our understanding of health and disease.

A cross-sectional study of the association between exposure to violence, intelligence, and executive function in Brazilian youths

We carried out an exploratory study of the association between exposure to violence, intelligence, and executive functions in Brazilian preadolescents. The study included 56 participants (31 males) aged 8 to 14 years old (mean = 11.3, SD = 1.0). We administered neuropsychological tests to evaluate executive functions and the Juvenile Victimization Questionnaire (JVQ) to evaluate exposure to violence. We used the following neuropsychological instruments: Wechsler Abbreviated Scale of Intelligence (WASI), Stroop Color-Word Interference task, digits subtest of the Wechsler Intelligence Scale for Children, and an N-back task. We generated a composite score from neuropsychological test scores and investigated the association of that score, and individual test scores, with exposure to violence and socioeconomic status (SES). Results suggest, first, that exposure to violence is associated with a 0.5-point lower intelligence quotient score for every reported victimization event in the Juvenile Victimization Questionnaire. Results also show that the digits backward subtest scores showed a significant negative correlation with exposure to violence (JVQ; rho = -0.29, p < 0.05); both analyses were adjusted for the level of schooling of parents or guardians, which was also found to be significantly associated with lower intelligence quotient scores. We discuss results in the light of the existing literature on the effects of exposure to violence on adolescent development, and the amounting evidence that suggests an association of exposure to violence, and of victimization, with tests that evaluate constructs of executive functions. The study struggled with low compliance from participants, and we underscore the challenges of carrying out empirical studies aimed at better understanding the development of underrepresented youths, such as those from Central and Latin America.

Parental psychosocial factors predicting adolescents' psychological adjustment during the surging and remission periods of COVID-19 in China: A longitudinal study

BACKGROUND

Parents play a critical role in adolescents' psychological adjustment, especially in stress response. Few studies have investigated parental impact on adolescents' psychological adjustment in the pandemic. The longitudinal study examined how parental psychosocial factors at the surging period of the pandemic (T1) in China predicted adolescents' anxiety and depression concurrently and at the remission periods three (T2) and six months (T3) later.

METHODS

Middle and high school students and their parents from three schools in Shanghai, China, completed online surveys on March 10, 2020 (T1), June 16, 2020 (T2), and Sep 25, 2020 (T3). Adolescents' anxiety/depression levels were assessed by matching self- and parent-reports at T1, T2, T3, and parents reported their psychological state (emotion and psychopathology), pandemic response (appraisal and coping), and perceived social support (PSS) at T1.

RESULTS

Parental positive/negative emotions, anxiety, depression, control-appraisal, forward- and trauma-focus coping style and PSS were all significantly related to their children's anxiety/depression at T1. All factors, except coping style, predicted adolescents' anxiety/depression at T2 and T3, even after controlling for T1 adjustment levels. Parental positive emotion and depression had the strongest impact on adolescents' adjustment.

LIMITATIONS

Some participants didn't complete the surveys at later time points, and the participants were only recruited in Shanghai.

CONCLUSIONS

The study found that parents' psychosocial factors played a pivotal role on adolescents' psychological adjustment during COVID-19, highlighting the need to provide help to parents who were suffering from potential psychological distress.

Perceived stress and rejection associated with functional network strength during memory retrieval in adolescents

The brain undergoes substantial structural and functional remodeling during adolescence, including alterations in memory-processing regions influenced by stress. This study evaluated brain activation using functional magnetic resonance imaging (fMRI) during spatial memory performance using a virtual Morris water task (MWT) and examined the associations between default mode network (DMN) activation, task performance, and perceived stress and rejection. Functional magnetic resonance imaging data were acquired at 3 Tesla from 59 (34 female) adolescents (13-14 years). The NIH Emotion Toolbox was used to measure perceived stress and rejection. During the MWT, hippocampus and prefrontal cortex showed greater activation during memory retrieval relative to motor performance. Templates of brain functional networks from the Human Connectome Project study were used to extract individual participants' brain network activation strengths for the retrieval > motor contrast for two sub-networks of the default mode network: medial temporal lobe (MTL-DMN) and dorsomedial prefrontal (dMPFC-DMN). For the MTL-DMN sub-network only, activation was significantly associated with worse MWT performance (p = .008) and greater perceived stress (p = .008) and perceived rejection (p = .002). Further, MWT performance was negatively associated with perceived rejection (p = .007). These findings suggest that perceived stress and rejection are related to engagement of MTL-DMN during spatial memory and that engagement of this network impacts performance. These findings also demonstrate the utility of examining task-related network activation strength to identify the impact of perceived stress and rejection on large-scale brain network functioning during adolescence.

Unaffected Memory and Inhibitory Functioning Several Weeks Postpartum in Women with Pregnancy Complicated by Preeclampsia

Several studies reported impaired cognitive functioning after pregnancy complicated by preeclampsia. The present study examined cognitive and executive functioning in women with preeclampsia at a time at which immediate effects of gestation have resolved, brain damage due to other risk factors have not yet manifested, and impairments may thus primarily occur as a result of the huge stress induced by the potentially life threatening condition. Verbal learning/memory (California Verbal Learning Test) and inhibitory functioning (Mittenecker Pointing Test) of 35 women with preeclampsia and 38 women with uncomplicated pregnancy were followed over five measurement time points during the period from 16 to 48 weeks postpartum. A further control group comprised 40 women with no history of recent pregnancy. The groups did not differ in their verbal learning/memory performance. Higher levels of currently experienced everyday-life stress were associated with poorer inhibitory control/greater stereotypy in responding, but this effect was not directly connected with pregnancy complications. Taken together, the findings do not indicate rapid-onset cognitive impairment after preeclampsia, brought about by its extremely stressful nature or other factors that take effect during gestation. Deficits observed in later life may develop on a long-term basis through late-diagnosed hypertension and unfavorable lifestyle factors. The large time window in which exaggerated cognitive decline can be prevented or mitigated should be utilized for the control of risk factors and interventions to improve lifestyle where appropriate.

The brief daily stressors screening tool: An introduction and evaluation

The present study introduces a short screening instrument for the measurement of experienced general daily stressors across different life domains that can be used in large-scale studies. The brief daily stressors screening tool (BDSST) assesses the experience of general daily stressors in eight distinct life domains. General daily stressors are indicated for the past 12-months on a five-point Likert scale. The present study evaluates the BDSST in two successive studies. The first study was conducted in a representative German sample (n = 7,849). The second study was conducted to assess one-month-retest-stability in another representative German sample (n = 1,294). The BDSST shows promising psychometric properties. It has a skewed positive distribution, internal consistency and stability are acceptable and its one-factor structure was confirmed in a bifactor confirmatory factor analysis. The BDSST is a reliable and valid short instrument for the assessment of experienced general daily stressors in large-scale studies and routine clinical practise. For in-depth clinical assessment, it can be used to identify relevant life domains for further investigation.

Individual differences in accumbofrontal tract integrity relate to risky decisions under stress in adolescents and adults

Psychosocial stress increases risky decision-making (DM). It is widely accepted that individual variation in neural phenotypes underlie variability in this behavioral tendency in adults, but is less examined in adolescents. Our goal was to test the hypothesis that the relation between neural phenotypes and stress-related risky DM is better characterized by individual variation than by age. Using diffusion tensor imaging (DTI) tractography to characterize the accumbofrontal tract, we determined if it uniquely moderated how stress affects risky DM, over and above age. A daily diary design monitored participants’ daily stress for two weeks. Participants completed a DTI scan and performed a task in which decisions varied by expected value, once each on a day when they endorsed feeling higher (and lower) than usual levels of stress. Multilevel logistic regression analyses revealed that all participants were more likely to take risks as expected reward value increased; this behavior was greater under high versus low stress for individuals with low accumbofrontal tract integrity, whereas DM was less influenced by stress for individuals with high accumbofrontal tract integrity, regardless of age. Results suggest that individual differences in brain structure may be more germane to characterizing risky decisions in adolescents, rather than ontogeny.

Chronic stress, executive functioning, and real-life self-control: An experience sampling study

OBJECTIVE

To test the hypothesis that chronic stress impairs the use of cognitive control for self-control, we examined how chronic stress affects the relation between individual differences in general executive functioning (GEF) and self-control in real-life situations.

METHOD

About 338 young adults with varying degrees of chronic stress underwent experience sampling of real-life self-control for 7 days and completed a battery of nine executive function tasks from which a latent variable representing individual differences in GEF was derived.

RESULTS

Structural equation models showed that higher levels of chronic stress were associated with stronger desires and a less negative relationship between GEF and desire strength. Chronic stress and GEF did not predict desire enactment in situations where effortful resistance was attempted.

CONCLUSIONS

These findings suggest that chronic stress may impair self-control by reducing the use of cognitive control for "early" desire regulation strategies while leaving "late" resistance strategies unaffected. That relationships between executive functioning and real-life self-control can be moderated by third factors such as chronic stress may to some extent explain the common finding of weak or missing associations between laboratory measures of executive functioning and real-life self-control.

Stress and nicotine during adolescence disrupts adult hippocampal-dependent learning and alters stress reactivity

Adolescence represents increased susceptibility to stress that increases risk for nicotine dependence. The present study examined the interactive effects of brief exposure to stress (shipping/transportation or experimentally induced) and chronic nicotine during adolescence on cognitive function and stress reactivity in adulthood. Adolescent (P31), but not young adult (P47), C57BL/6J mice had higher levels of corticosterone after shipping vs mice bred onsite. Shipped preadolescent (P23) and adolescent (P38) mice, but not those bred onsite, exposed to nicotine showed deficits in contextual fear learning when tested in adulthood. Adult learning deficits were replicated in adolescent mice bred onsite, exposed to experimentally induced stress, and administered chronic nicotine. Stress and nicotine during adolescence resulted in higher expression of hippocampal glucocorticoid receptors and corticotropin-releasing factor receptors and blunted restraint induced CORT release in adulthood. Importantly, studies examining adolescent behavior in mice should consider stress influences outcomes.

An fMRI study of inhibitory control and the effects of exposure to violence in Latin-American early adolescents: alterations in frontoparietal activation and performance

We used functional magnetic resonance to investigate the effects of exposure to violence on early adolescent brain function in an inhibitory control task. We investigated the association among scores on self-reported exposure to violence, performance and brain activation. Thirty-seven early adolescents (ages 10-14) from a Latin-American urban region participated in the study. Results showed that recent and chronic exposure to violence was associated with less activation of a network of frontal regions, including the anterior cingulate gyrus and the superior frontal cortex; recent exposure to violence was also associated with less activation of the superior parietal lobe. Results also showed that less activation correlated with more prominent deterioration in the performance in the inhibitory control task (increased latency with time). The findings suggest that early adolescence exposure to violence is associated with differences in activation of a neural network commonly associated with executive function and control. The results underscore the urgency of addressing exposure to violence in adolescence, a period of high susceptibility to the environment, and are discussed in the light of the evidence of the effects of violence on adolescent brain function. Executive function training may be a candidate for targeted cognitive interventions aimed at mitigating these effects.

Violence and Latin-American preadolescents: A study of social brain function and cortisol levels

The present study investigated exposure to violence and its association with brain function and hair cortisol concentrations in Latin-American preadolescents. Self-reported victimization scores (JVQ-R2), brain imaging (fMRI) indices for a social cognition task (the 'eyes test'), and hair cortisol concentrations were investigated, for the first time, in this population. The eyes test is based on two conditions: attributing mental state or sex to pictures of pairs of eyes (Baron-Cohen, Wheelwright, Hill, Raste, & Plumb, 2001). The results showed an association among higher victimization scores and (a) less activation of posterior temporoparietal right-hemisphere areas, in the mental state condition only (including right temporal sulcus and fusiform gyrus); (b) higher functional connectivity indices for the Amygdala and Right Fusiform Gyrus (RFFG) pair of brain regions, also in the mental state condition only; (c) higher hair cortisol concentrations. The results suggest more exposure to violence is associated with significant differences in brain function and connectivity. A putative mechanism of less activation in posterior right-hemisphere regions and of synchronized Amygdala: RFFG time series was identified in the mental state condition only. The results also suggest measurable effects of exposure to violence in hair cortisol concentrations, which contribute to the reliability of self-reported scores by young adolescents. The findings are discussed in light of the effects of exposure to violence on brain function and on social-cognitive development in the adolescent brain. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=qHcXq7Y9PBk.

A study of the relationship between adverse childhood experiences, life events, and executive function among college students in China

Objective

The aim of this study was to investigate the effects of adverse childhood experiences and life events on the inhibitory control ability, cognitive flexibility, and working memory of college students.

Methods

The study involved testing the participants using the Adverse Childhood Experiences (ACEs) Questionnaire, the Adolescent Life Events Scale (Adolescent Self-rating Life Events Checklist, ASLEC), and the program of executive functions designed by E-prime software.

Results

The incidence rate of ACEs was 44.8%. ACEs, life events, and inhibition ability were found to have a significant correlation (r1 = 0.50, r1 = 0.47, p < 0.01). In the switching task, the reaction time of the ACEs group was longer than the reaction time of the non-ACEs group (t = − 2.55, p < 0.05). Low scorers in the ASLEC exhibited lesser reaction times than their high-scoring counterparts in the tasks related to inhibition, switching, and working memory experiments. The regression analysis results showed that ACEs and life events had a possibility rate of 56% in predicting inhibition ability.

Conclusions

The incidence of ACEs was found to be high, and cognitive flexibility is significantly influenced by ACEs. Life events have a significant impact on inhibition ability, cognitive flexibility, and working memory. ACEs and life events were found to be reliable predictors of inhibition ability.

Self-Efficacy as a Mechanism Linking Daily Stress to Mental Health in Students: A Three-Wave Cross-Lagged Study

BACKGROUND AND OBJECTIVES

While stress is generally well established to be predictive for different indicators of mental health, little is known about the longitudinal effects of daily life stressors and the role of self-evaluation factors. We tested whether perceived general self-efficacy is a mediator for the association between daily life stressors and psychopathological symptoms as well as subjective well-being.

METHODS

Data derived from 2160 Chinese university students was assessed at three time points with one-year intervals. We used the Brief Daily Stressor Screening, the General Self-Efficacy Scale, the Positive Mental Health Scale, and the Depression Anxiety and Stress Scales. Total, direct, and indirect effects were estimated using 95% bootstrapped confidence intervals and structural equation modeling.

RESULTS

Latent variable mediation analyses showed that daily stressors were associated with increased symptoms of depression, anxiety, and stress and with decreased subjective well-being. All cross-lagged mediational paths via self-efficacy were significant in predicting positive and negative mental health.

CONCLUSIONS

Considering stress of daily life as well as including the two dimensions of mental health may be important for future research and practice. This study provides novel evidence for mediating stress effects by perceived self-efficacy, which should be focused in intervention- and prevention-based approaches.

The Promise and Challenges of Intensive Longitudinal Designs for Imbalance Models of Adolescent Substance Use

Imbalance models of adolescent brain development attribute the increasing engagement in substance use during adolescence to within-person changes in the functional balance between the neural systems underlying socio-emotional, incentive processing, and cognitive control. However, the experimental designs and analytic techniques used to date do not lend themselves to explicit tests of how within-person change and within-person variability in socio-emotional processing and cognitive control place individual adolescents at risk for substance use. For a more complete articulation and a more stringent test of these models, we highlight the promise and challenges of using intensive longitudinal designs and analysis techniques that encompass many (often >10) within-person measurement occasions. Use of intensive longitudinal designs will lend researchers the tools required to make within-person inferences in individual adolescents that will ultimately align imbalance models of adolescent substance use with the methodological frameworks used to test them.

Prefrontal cortex executive processes affected by stress in health and disease

Prefrontal cortical executive functions comprise a number of cognitive capabilities necessary for goal directed behavior and adaptation to a changing environment. Executive dysfunction that leads to maladaptive behavior and is a symptom of psychiatric pathology can be instigated or exacerbated by stress. In this review we survey research addressing the impact of stress on executive function, with specific focus on working memory, attention, response inhibition, and cognitive flexibility. We then consider the neurochemical pathways underlying these cognitive capabilities and, where known, how stress alters them. Finally, we review work exploring potential pharmacological and non-pharmacological approaches that can ameliorate deficits in executive function. Both preclinical and clinical literature indicates that chronic stress negatively affects executive function. Although some of the circuitry and neurochemical processes underlying executive function have been characterized, a great deal is still unknown regarding how stress affects these processes. Additional work focusing on this question is needed in order to make progress on developing interventions that ameliorate executive dysfunction.

Early life stress, FK506 binding protein 5 gene (FKBP5) methylation, and inhibition-related prefrontal function: A prospective longitudinal study

Individuals who have experienced high levels of childhood stress are at increased risk for a wide range of behavioral problems that persist into adulthood, yet the neurobiological and molecular mechanisms underlying these associations remain poorly understood. Many of the difficulties observed in stress-exposed children involve problems with learning and inhibitory control. This experiment was designed to test individuals' ability to learn to inhibit responding during a laboratory task. To do so, we measured stress exposure among a community sample of school-aged children, and then followed these children for a decade. Those from the highest and lowest quintiles of childhood stress exposure were invited to return to our laboratory as young adults. At that time, we reassessed their life stress exposure, acquired functional magnetic resonance imaging data during an inhibitory control task, and assayed these individuals' levels of methylation in the FK506 binding protein 5 (FKBP5) gene. We found that individuals who experienced high levels of stress in childhood showed less differentiation in the dorsolateral prefrontal cortex between error and correct trials during inhibition. This effect was associated only with childhood stress exposure and not by current levels of stress in adulthood. In addition, FKBP5 methylation mediated the association between early life stress and inhibition-related prefrontal activity. These findings are discussed in terms of using multiple levels of analyses to understand the ways in which adversity in early development may affect adult behavioral adaptation.

Adolescents, neurosciences et prise de décisions médicales : devrions-nous revoir certaines dispositions du Code civil du Québec?

Au Québec, le mineur de 14 ans et plus peut consentir seul aux soins médicaux requis par son état de santé, sauf exception. Or, les données provenant des neurosciences indiquent que : 1) l’acquisition de la « maturité cérébrale » est un processus continu, pouvant durer jusqu’à la mi-vingtaine, et que 2) certaines habiletés décisionnelles de l’adolescent, comme l’évaluation des risques et bénéfices à court et à long terme, seraient différentes de celles des adultes, surtout dans les situations émotivement chargées. Nous soumettons que, dans une perspective de protection de l’intérêt supérieur de l’enfant, la réalité neurophysiologique de l’adolescent devrait être prise en compte en contexte de soins de santé. Ainsi, nous questionnons le caractère adéquat de la présomption de capacité d’exercer un jugement de façon autonome dès l’âge de 14 ans et soulignons l’aspect paradoxal de la possibilité d’une intervention judiciaire en cas de refus de traitement. Nous questionnons également la pertinence de considérations d’âge dans le cadre de la relation entre le médecin et son patient, dès lors que la détermination de la capacité décisionnelle est une composante essentielle de l’obtention d’un consentement libre et éclairé. Enfin, nous questionnons l’exclusion des parents du processus décisionnel, à la fois en regard de leur responsabilité parentale et des bénéfices que peuvent représenter leurs conseils pour l’adolescent. Par conséquent, nous soumettons qu’une évaluation du bien-fondé de l’octroi d’un pouvoir décisionnel à l’adolescent de 14 ans et plus serait souhaitable et qu’un régime uniformisé tout au long de la minorité, avec de possibles exceptions, reflèterait mieux les connaissances scientifiques actuelles.

Inhibitory Control Mediates the Association between Perceived Stress and Secure Relationship Quality

Past research has demonstrated negative associations between exposure to stressors and quality of interpersonal relationships among children and adolescents. Nevertheless, underlying mechanisms of this association remain unclear. Chronic stress has been shown to disrupt prefrontal functioning in the brain, including inhibitory control abilities, and evidence is accumulating that inhibitory control may play an important role in secure interpersonal relationship quality, including peer problems and social competence. In this prospective longitudinal study, we examine whether changes in inhibitory control, measured at both behavioral and neural levels, mediate the association between stress and changes in secure relationship quality with parents and peers. The sample included 167 adolescents (53% males) who were first recruited at age 13 or 14 years and assessed annually three times. Adolescents' inhibitory control was measured by their behavioral performance and brain activities, and adolescents self-reported perceived stress levels and relationship quality with mothers, fathers, and peers. Results suggest that behavioral inhibitory control mediates the association between perceived stress and adolescent's secure relationship quality with their mothers and fathers, but not their peers. In contrast, given that stress was not significantly correlated with neural inhibitory control, we did not further test the mediation path. Our results highlight the role of inhibitory control as a process through which stressful life experiences are related to impaired secure relationship quality between adolescents and their mothers and fathers.

Examining the influence of perceived stress on developmental change in memory and perceptual speed for adopted and nonadopted individuals

The present study prospectively evaluated cumulative early life perceived stress in relation to differential change in memory and perceptual speed from middle childhood to early adulthood. We aimed to identify periods of cognitive development susceptible to the effects of perceived stress among both adopted and nonadopted individuals. The sample consisted of participants in the Colorado Adoption Project (CAP, N = 690). Structured latent growth curves were fit to 4 memory outcomes as well as 1 perceptual speed outcome, which described nonlinear change between ages 9 and 30. Both adoption status and cumulative perceived stress indices served as predictors of the latent curves. The perceived stress indices were constructed from the Brooks-Gunn Life Events Scale for Adolescents, and reflected "upsettingness" ratings associated with the occurrence of particular life events during middle childhood (ages 9 to 12) and adolescence (ages 13 to 16). For memory and perceptual speed, cumulative perceived stress did not predict differential cognitive gains. However, differences in perceptual speed trajectories between nonadopted and adopted individuals were observed, with adopted individuals showing smaller gains. Although these findings provide no evidence that emergent variability in memory and perceptual speed trajectories by age 30 are explained by cumulative perceptions of stress in childhood and adolescence, further investigations regarding potential vulnerability across the life span are warranted. (PsycINFO Database Record

Stress and adolescent hippocampal neurogenesis: diet and exercise as cognitive modulators

Adolescence is a critical period for brain maturation. Deciphering how disturbances to the central nervous system at this time affect structure, function and behavioural outputs is important to better understand any long-lasting effects. Hippocampal neurogenesis occurs during development and continues throughout life. In adulthood, integration of these new cells into the hippocampus is important for emotional behaviour, cognitive function and neural plasticity. During the adolescent period, maturation of the hippocampus and heightened levels of hippocampal neurogenesis are observed, making alterations to neurogenesis at this time particularly consequential. As stress negatively affects hippocampal neurogenesis, and adolescence is a particularly stressful time of life, it is important to investigate the impact of stressor exposure at this time on hippocampal neurogenesis and cognitive function. Adolescence may represent not only a time for which stress can have long-lasting effects, but is also a critical period during which interventions, such as exercise and diet, could ameliorate stress-induced changes to hippocampal function. In addition, intervention at this time may also promote life-long behavioural changes that would aid in fostering increased hippocampal neurogenesis and cognitive function. This review addresses both the acute and long-term stress-induced alterations to hippocampal neurogenesis and cognition during the adolescent period, as well as changes to the stress response and pubertal hormones at this time which may result in differential effects than are observed in adulthood. We hypothesise that adolescence may represent an optimal time for healthy lifestyle changes to have a positive and long-lasting impact on hippocampal neurogenesis, and to protect against stress-induced deficits. We conclude that future research into the mechanisms underlying the susceptibility of the adolescent hippocampus to stress, exercise and diet and the consequent effect on cognition may provide insight into why adolescence may be a vital period for correct conditioning of future hippocampal function.

Stress, coping, executive function, and brain activation in adolescent offspring of depressed and nondepressed mothers

This study examined the associations among chronic stress, activation in the prefrontal cortex (PFC), executive function, and coping with stress in at-risk and a comparison sample of adolescents. Adolescents (N = 16; age 12-15) of mothers with (n = 8) and without (n = 8) a history of depression completed questionnaires, neurocognitive testing, and functional neuroimaging in response to a working memory task (N-back). Children of depressed mothers demonstrated less activation in the anterior PFC (APFC) and both greater and less activation than controls in distinct areas within the dorsal anterior cingulate cortex (dACC) in response to the N-back task. Across both groups, activation of the dorsolateral PFC (DLPFC; Brodmann area [BA9]) and APFC (BA10) was positively correlated with greater exposure to stress and negatively correlated with secondary control coping. Similarly, activation of the dACC (BA32) was negatively correlated with secondary control coping. Regression analyses revealed that DLPFC, dACC, and APFC activation were significant predictors of adolescents' reports of their use of secondary control coping and accounted for the effects of stress exposure on adolescents' coping. This study provides evidence that chronic stress may impact coping through its effects on the brain regions responsible for executive functions foundational to adaptive coping skills.

Exploring Temporal Patterns of Stress in Adolescent Girls with Headache

As part of a larger study on perceived stress and headaches in 2009, momentary perceived stress, head pain levels and stress-related symptom data were collected. This paper explores a temporal analysis of the patterns of stress, as well as an analysis of momentary and retrospective stress-related symptoms compared by level of headache activity. Adolescent girls (N = 31) ages 14-18 were randomly cued by electronic diaries 7 times per day over a 21-day period responding to momentary questions about level of head pain, perceived stress and stress-related symptoms. Multivariate general linear modelling was used to determine significant differences among headache groups in relation to temporal patterns of stress. Significant headache group differences were found on retrospective and momentary stress-related symptom measures. A total of 2841 diary responses captured stress levels, head pain and related symptoms. The chronic headache (CH) group reported the highest levels of hourly and daily stress, followed by the moderate headache (MH) and low headache (LH) groups. Patterns of stress for the three headache groups were statistically distinct, illustrating increased stress in girls with more frequent head pain. This evidence suggests that because of increased stress, girls with recurrent head pain are likely a vulnerable population who may benefit from stress-reducing interventions. Copyright © 2016 John Wiley & Sons, Ltd.

Functional connectivity of resting-state, working memory and inhibition networks in perceived stress

Experimental imaging studies on the effects of acute stress have revealed functional changes in the amygdalae, hippocampi and medial frontal cortices. However, much less is known about the association between perceived stress and neurological function which may have implications for the development of stress related disorders. Participants completed a working-memory task and an inhibition task whilst undergoing a functional magnetic resonance imaging (fMRI) scan. Task related and resting-state fMRI data from 22 women and 24 men were analysed to investigate changes in task activations and functional connectivity associated with perceived stress over the past month. Analyses were stratified by gender due to gender differences in the stress response. Stress was associated with faster working memory response time in women, but not men. Stress was not associated with any differences in task activations in either gender. There were many significant associations between stress and connectivity: findings in women were consistent with increased emotional regulation; men exhibited decreases in connectivity between affective processing areas during the tasks and showed no relation between perceived stress and resting-state connectivity; very few of the within gender differences were significantly different between gender. Dysregulated connectivity between areas involved in the neural stress response and self-referential thoughts (e.g. the default mode network) suggests that perceived stress may have a subtle impact on cognitive processing and neural correlates.

Stress and the adolescent brain: Amygdala-prefrontal cortex circuitry and ventral striatum as developmental targets

Adolescence is a time in development when significant changes occur in affective neurobiology. These changes provide a prolonged period of plasticity to prepare the individual for independence. However, they also render the system highly vulnerable to the effects of environmental stress exposures. Here, we review the human literature on the associations between stress-exposure and developmental changes in amygdala, prefrontal cortex, and ventral striatal dopaminergic systems during the adolescent period. Despite the vast differences in types of adverse exposures presented in his review, these neurobiological systems appear consistently vulnerable to stress experienced during development, providing putative mechanisms to explain why affective processes that emerge during adolescence are particularly sensitive to environmental influences.

Effects of post-traumatic growth on the dorsolateral prefrontal cortex after a disaster

The relating to others factor of post-traumatic growth (PTG), which involves mutual help and a strong sense of connection with humanity, is important for young people who are coping with stress. The prefrontal cortex (PFC), especially the dorsolateral PFC (DLPFC), may play an important role in post-traumatic stress disorder (PTSD) with regard to coping and resilience. We hypothesized that the neural correlates of PTG may be responsible for resilience to the correlates of PTSD. Our study tested this hypothesis by examining whether measures of PTG, particularly the measures of relating to others after a disaster, were associated with increased regional grey matter volume (rGMV) in the PFC by assessing individuals who had experienced the East Japan Great Earthquake. We calculated the delta-rGMV by subtracting the rGMV obtained 3 months before the disaster from the rGMV obtained after this disaster using voxel-based morphometry. The magnetic resonance imaging data obtained from 26 subjects (M/F: 21/5; age: 21.2 ± 1.6 yrs.) showed that the total scores on a PTG inventory and the subscore for relating to others at the post-assessment were positively and significantly associated with the delta-rGMV in the right DLPFC. The DLPFC seems to be the main neural correlate of PTG.

Isolating biomarkers for symptomatic states: considering symptom-substrate chronometry

A long-standing goal of psychopathology research is to develop objective markers of symptomatic states, yet progress has been far slower than expected. Although prior reviews have attributed this state of affairs to diagnostic heterogeneity, symptom comorbidity and phenotypic complexity, little attention has been paid to the implications of intra-individual symptom dynamics and inter-relatedness for biomarker study designs. In this critical review, we consider the impact of short-term symptom fluctuations on widely used study designs that regress the 'average level' of a given symptom against biological data collected at a single time point, and summarize findings from ambulatory assessment studies suggesting that such designs may be sub-optimal to detect symptom-substrate relationships. Although such designs have a crucial role in advancing our understanding of biological substrates related to more stable, longer-term changes (for example, gray matter thinning during a depressive episode), they may be less optimal for the detection of symptoms that exhibit high frequency fluctuations, are susceptible to common reporting biases, or may be heavily influenced by the presence of other symptoms. We propose that a greater emphasis on intra-individual symptom chronometry may be useful for identifying subgroups of patients with common, proximal pathological indicators. Taken together, these three recent developments in the areas of symptom conceptualization and measurement raise important considerations for future studies attempting to identify reliable biomarkers in psychiatry.

Reduced Inhibitory Control Mediates the Relationship Between Cortical Thickness in the Right Superior Frontal Gyrus and Body Mass Index

Unhealthy eating behaviors often develop in the setting of inadequate inhibitory control, a function broadly ascribed to the prefrontal cortex (PFC). Regulation of inhibitory control by the PFC and its anatomical components and their contribution to increasing body mass index (BMI) are poorly understood. To study the role of PFC in the regulation of inhibitory control and body weight, we examined measures of cortical thickness in PFC sub-regions, inhibitory control (color-word interference task (CWIT)), and BMI in 91 healthy volunteers. We tested the predictive effect of PFC sub-regional cortical thickness on BMI and mediation by inhibitory control measured with CWIT. Measures of depression (BDI-II), anxiety (STAI-T) and trauma-related symptoms (TSC-40) were collected; the disinhibition scale of the three-factor eating questionnaire (TFEQ) was used to assess disinhibited eating. We then tested the relationship between BD-II, STAI-T, TSC-40, TFEQ, CWIT, and BMI with correlation analyses. Right superior frontal gyrus cortical thickness significantly predicted BMI (β=-0.91; t=-3.2; p=0.002). Mediation analysis showed a significant indirect effect of cortical thickness on BMI mediated by inhibitory control (95% CI=-6.1, -0.67). BMI was unrelated to BDI-II, STAI-T, TSC-40, or TFEQ scores. We found an inverse relationship between cortical thickness in the right-superior frontal gyrus and BMI, which was fully mediated by inhibitory control neurocognitive performance. Our results suggest possible targets for neuromodulation in obesity (ie superior frontal gyrus) and a quantifiable mediator of their effects (ie inhibitory control).

Nicotine, adolescence, and stress: A review of how stress can modulate the negative consequences of adolescent nicotine abuse

In order to continue the decline of smoking prevalence, it is imperative to identify factors that contribute to the development of nicotine and tobacco addiction, such as adolescent initiation of nicotine use, adolescent stress, and their interaction. This review highlights the biological differences between adolescent and adults in nicotine use and resulting effects, and examines the enduring consequences of adolescent nicotine administration. A review of both clinical and preclinical literature indicates that adolescent, but not adult, nicotine administration leads to increased susceptibility for development of long-lasting impairments in learning and affect. Finally, the role stress plays in normal adolescent development, the deleterious effects stress has on learning and memory, and the negative consequences resulting from the interaction of stress and nicotine during adolescence is reviewed. The review concludes with ways in which future policies could benefit by addressing adolescent stress as a means of reducing adolescent nicotine abuse.

Executive Attention Impairment in Adolescents With Major Depressive Disorder

Neural network models that guide neuropsychological assessment practices are increasingly used to explicate depression, though a paucity of work has focused on regulatory systems that are under development in adolescence. The purpose of this study was to evaluate subsystems of attention related to executive functioning including alerting, orienting, and executive attention networks, as well as sustained attention with varying working memory load, in a sample of depressed and well adolescents. Neuropsychological functioning in 99 adolescents diagnosed with major depressive disorder (MDD) and 63 adolescent healthy controls (M = 16.6 years old) was assessed on the Attention Network Test (ANT) and the Continuous Performance Test, Identical Pairs. Adolescents with MDD, particularly those who were not medicated, were slower to process conflict (slower reaction time on the Executive Attention scale of the ANT) compared to controls, particularly for those who were not undergoing psychopharmacological treatment. Tentative evidence also suggests that within the MDD group, orienting performance was more impaired in those with a history of comorbid substance use disorder, and alerting was more impaired in those with a history of a suicide attempt. Adolescents with depression showed impaired executive attention, although cognitive performance varied across subgroups of patients. These findings highlight the importance of examining neurocognitive correlates associated with features of depression and suggest an avenue for future research to help guide the development of interventions.

Npas4 deficiency increases vulnerability to juvenile stress in mice

During specific windows of postnatal brain development, individuals are particularly susceptible to developing mental illnesses in adulthood. Adolescence is such a window during which environmental stress can have long-lasting consequences on social and cognitive functions. In individuals, highly vulnerable to stress, a relatively mild stressful situation can trigger the onset of psychiatric conditions. The genetic factors and mechanisms underlying vulnerability to stress are not well understood. Here, we show that variations in expression of the brain-specific transcription factor Npas4 contributes to the long-term consequences of juvenile stress on cognitive abilities. We observed that transgenic Npas4-deficient mice exposed to chronic mild stress during adolescence (but not during adulthood) develop prefrontal cortex-dependent cognitive deficits in adulthood, while the same stress did not affect Npas4 wild-type mice. These cognitive deficits were accompanied by fewer neuroblasts in the subventricular zone, and reduced ability of these immature neuronal cells to migrate away from this neurogenic zone toward cortical regions. These findings suggest for the first time that the transcription factor Npas4 could play a significant role in coping with juvenile stress. They also suggest that Npas4 could modulate resilience or vulnerability to stress by mediating the effects of stress on neurogenesis.

Monoamine-sensitive developmental periods impacting adult emotional and cognitive behaviors

Development passes through sensitive periods, during which plasticity allows for genetic and environmental factors to exert indelible influence on the maturation of the organism. In the context of central nervous system development, such sensitive periods shape the formation of neurocircuits that mediate, regulate, and control behavior. This general mechanism allows for development to be guided by both the genetic blueprint as well as the environmental context. While allowing for adaptation, such sensitive periods are also vulnerability windows during which external and internal factors can confer risk to disorders by derailing otherwise resilient developmental programs. Here we review developmental periods that are sensitive to monoamine signaling and impact adult behaviors of relevance to psychiatry. Specifically, we review (1) a serotonin-sensitive period that impacts sensory system development, (2) a serotonin-sensitive period that impacts cognition, anxiety- and depression-related behaviors, and (3) a dopamine- and serotonin-sensitive period affecting aggression, impulsivity and behavioral response to psychostimulants. We discuss preclinical data to provide mechanistic insight, as well as epidemiological and clinical data to point out translational relevance. The field of translational developmental neuroscience has progressed exponentially providing solid conceptual advances and unprecedented mechanistic insight. With such knowledge at hand and important methodological innovation ongoing, the field is poised for breakthroughs elucidating the developmental origins of neuropsychiatric disorders, and thus understanding pathophysiology. Such knowledge of sensitive periods that determine the developmental trajectory of complex behaviors is a necessary step towards improving prevention and treatment approaches for neuropsychiatric disorders.

Partial genetic deletion of neuregulin 1 and adolescent stress interact to alter NMDA receptor binding in the medial prefrontal cortex

Schizophrenia is thought to arise due to a complex interaction between genetic and environmental factors during early neurodevelopment. We have recently shown that partial genetic deletion of the schizophrenia susceptibility gene neuregulin 1 (Nrg1) and adolescent stress interact to disturb sensorimotor gating, neuroendocrine activity and dendritic morphology in mice. Both stress and Nrg1 may have converging effects upon N-methyl-D-aspartate receptors (NMDARs) which are implicated in the pathogenesis of schizophrenia, sensorimotor gating and dendritic spine plasticity. Using an identical repeated restraint stress paradigm to our previous study, here we determined NMDAR binding across various brain regions in adolescent Nrg1 heterozygous (HET) and wild-type (WT) mice using [³H] MK-801 autoradiography. Repeated restraint stress increased NMDAR binding in the ventral part of the lateral septum (LSV) and the dentate gyrus (DG) of the hippocampus irrespective of genotype. Partial genetic deletion of Nrg1 interacted with adolescent stress to promote an altered pattern of NMDAR binding in the infralimbic (IL) subregion of the medial prefrontal cortex. In the IL, whilst stress tended to increase NMDAR binding in WT mice, it decreased binding in Nrg1 HET mice. However, in the DG, stress selectively increased the expression of NMDAR binding in Nrg1 HET mice but not WT mice. These results demonstrate a Nrg1-stress interaction during adolescence on NMDAR binding in the medial prefrontal cortex.