Mechanisms of neuroplasticity linking early adversity to depression: developmental considerations

Early adolescent development in the face of violence: A systematic review running

BACKGROUND

Exposure to violence has severe and lasting effects on development. Despite the body of research examining childhood exposures to violence and victimization, developmental outcomes during early adolescence are poorly understood.

OBJECTIVE

To synthesize existing research on the effects of violence exposure on early adolescent development (youth 9-14 years old) and highlight areas for future research.

METHOD

We conducted a systematic search of PubMed, CINAHL, Web of Science, Scopus, and EMBASE for articles published between 2012 and 2023. Included articles focused on violence exposure related to experiencing or observing community violence, witnessing domestic violence and/or being the victim of chronic physical abuse.

RESULTS

Twenty-eight articles spanning four developmental domains were included: behavioral, biological, neurological, and social development. Behaviorally, violence exposure posed significant effects on both internalizing and externalizing symptoms. Biologically, violence exposure was strongly associated with advanced epigenetic age, accelerated puberty, and insomnia. Neurologically, violence exposure had significant associations with both structural and functional differences in the developing brain. Socially, violence exposure was related to poor school engagement, peer aggression, and low social support.

CONCLUSION

This systematic review highlights varying effects of violence exposure on early adolescent development. The gaps presented should be addressed and implemented into clinical practice via evidence-based policies and procedures to ensure successful transition to adulthood.

Do dimensions of childhood adversity differ in their direct associations with youth psychopathology? A meta-analysis

Growing evidence supports the unique pathways by which threat and deprivation, two core dimensions of adversity, confer risk for youth psychopathology. However, the extent to which these dimensions differ in their direct associations with youth psychopathology remains unclear. The primary aim of this preregistered meta-analysis was to synthesize the associations between threat, deprivation, internalizing, externalizing, and trauma-specific psychopathology. Because threat is proposed to be directly linked with socioemotional development, we hypothesized that the magnitude of associations between threat and psychopathology would be larger than those with deprivation. We conducted a search for peer-reviewed articles in English using PubMed and PsycINFO databases through August 2022. Studies that assessed both threat and deprivation and used previously validated measures of youth psychopathology were included. One hundred and twenty-seven articles were included in the synthesis (N = 163,767). Results of our three-level meta-analyses indicated that adversity dimension significantly moderated the associations between adversity and psychopathology, such that the magnitude of effects for threat (r's = .21-26) were consistently larger than those for deprivation (r's = .16-.19). These differences were more pronounced when accounting for the threat-deprivation correlation. Additional significant moderators included emotional abuse and youth self-report of adversity. Findings are consistent with the Dimensional Model of Adversity and Psychopathology, with clinical, research, and policy implications.

Long-term Neighborhood Poverty Effects on Internalizing Symptoms in Adolescents: Mediated Through Allostatic Load and Pubertal Timing

PURPOSE

The long-term effect of neighborhood poverty on internalizing symptoms in adolescents and the biological mechanisms underlying this association remain unclear. We defined neighborhood poverty at the village level in two dimensions: intensity (i.e., poverty rate) and duration. This study investigated how the poverty rate and duration of exposure to neighborhood poverty interact to predict internalizing symptoms in adolescents through biological mechanisms (i.e., allostatic load and early pubertal timing).

METHODS

A total of 418 adolescents (50.2% girls; 11-14 years old; mean age = 12.57 years) living in rural China participated in two waves of data collection. Path analysis was conducted to examine the mediating role of allostatic load and pubertal timing in the relationship between the duration of exposure to neighborhood poverty and internalizing symptoms. Moreover, the interactive effect between the poverty rate and duration of neighborhood poverty on the allostatic load was tested.

RESULTS

The positive association between the duration of exposure to neighborhood poverty and internalizing symptoms of adolescents was explained by elevated allostatic load and early pubertal timing after adjusting for gender, age, prior family socioeconomic states and internalizing symptoms. The duration in neighborhood poverty was a stronger predictor of allostatic load for adolescents living in high poverty rate neighborhoods than for those living in low poverty rate neighborhoods.

DISCUSSION

Neighborhood poverty gets "under the skin" through biological pathways and affects internalizing symptoms among adolescents. The findings highlight the importance of considering different dimensions of neighborhood poverty (e.g., intensity and duration) on adolescents' health.

Stress inoculation during adolescence attenuates social stress-induced increase in ethanol intake in adult male mice

Social stress exposure heightens the risk of substance abuse disorder development, especially when endured during adolescence, influencing long-term mental health. This study investigates early-life stress's potential to confer resilience against later-life stressors. To investigate this hypothesis, we examined the impact of a single social defeat (SD) incident during adolescent mice's lives on subsequent voluntary ethanol consumption following repeated adult social stress exposure. Half of the adolescent mice experienced SD at postnatal day 28. Three weeks later (postnatal day 49), defeated groups encountered four confrontations with aggressive residents every 72 h, while control groups were exposed to non-resident exploration. A day after the last SD, defeated mice were classified as resilient or susceptible based on their response to a social interaction test (SIT), a model for depressive behavior. To assess ethanol consumption during young adulthood, researchers used the 'drinking in the dark' and oral ethanol self-administration paradigms. Stress inoculation (IS) slightly increased resilient animals in the SIT. In mice without IS exposure during adolescence, susceptible defeated mice displayed higher ethanol consumption and motivation than control and resilient mice. IS in adolescence effectively counteracted this effect, as IS-SD groups, whether resilient or susceptible, showed no increase in ethanol intake. These groups also exhibited similar motivation to control, measured by the progressive ratio. Notably, elevated IL-6 levels seen in SD-S mice were absent in IS-exposed mice. Additionally, IS-exposed groups had lower prefrontal cortex IL-6 and CX3CL1 levels. These findings support the hypothesis that IS, induced by moderate-intensity stress during adolescence, can enhance resilience to more severe stressors in adulthood.

Neighborhood Socioeconomic Disadvantage and White Matter Microstructure of the Arcuate Fasciculus and Uncinate Fasciculus in Adolescents

Background

Neighborhood- or area-level socioeconomic disadvantage is associated with neural alterations across the life span. However, few studies have examined the effects of neighborhood disadvantage on white matter microstructure during adolescence, an important period of development that coincides with increased risk for psychopathology.

Methods

In 200 adolescents (ages 13-20 years; 54.5% female, 4% nonbinary) recruited from 2 studies enriched for early adversity and depression, we examined whether neighborhood socioeconomic disadvantage derived from census tract data was related to white matter microstructure in several major white matter tracts. We also examined whether depressive symptoms and sex moderated these associations.

Results

Greater neighborhood socioeconomic disadvantage was associated with lower fractional anisotropy (FA) in the left arcuate fasciculus (β = -0.24, false discovery rate [FDR]-corrected p = .035) and right uncinate fasciculus (β = -0.32, FDR-corrected p = .002) above and beyond the effects of family-level socioeconomic status. Depressive symptoms significantly moderated the association between left arcuate fasciculus FA and both neighborhood (β = 0.17, FDR-corrected p = .026) and unemployment (β = 0.22, FDR-corrected p = .004) disadvantage such that these associations were only significant in adolescents who reported less severe depression. Sex did not moderate the association between socioeconomic disadvantage and FA in these tracts.

Conclusions

Greater neighborhood socioeconomic disadvantage, particularly poverty and educational attainment levels, was associated with lower FA in the arcuate fasciculus and uncinate fasciculus above and beyond the effects of family-level measures of socioeconomic status. These patterns were only observed in adolescents with low levels of depression, suggesting that we must be cautious about generalizing these findings to youths who struggle with mental health difficulties.

Aging alone and financial insecurity predict depression: a path analysis of objective and subjective indices

OBJECTIVES

This study draws on conservation of resources theory and transactional stress theory to guide our understanding of how social isolation, financial insecurity, and social support serve as a balance of both risk and protection for late-life depression.

METHODS

Data were from the Leave-Behind Questionnaire in the 2016 (N = 4293) and 2018 (N = 4714) waves of the Health and Retirement Study. We conducted a cross-sectional path analysis via structural equation modeling, including objective and subjective perspectives. The same model was tested in both samples.

RESULTS

Both social isolation and financial insecurity were associated with depression. We found several mediating risks and protective factors of these relationships. Objective financial status affected depression through both perceived financial insecurity and perceived social isolation, whereas objective isolation affected depression through perceived social support. This mediation model was -significant after adjusting for confounders.

CONCLUSION

This study underscores the importance of investigating the balance between risk and protection for depression, in the rising number of older adults aging alone in society. Findings suggest that objective and perceived measures offer unique windows into psychological constructs. Considering both objective and subjective perspectives may provide alternative targets for subsequent interventions to improve mental health in later life.

Depression in the next generation is related with maternal behaviors: A cross-comparison by alternating rat's mother care

This study investigated the potential impacts of depressive rats' maternal behavior as an early life stress on the outcome of offspring as an adulthood. Offspring from the same mother were divided into two groups, half of them were fostered or remained by a depressive mother, and the other half remained or fostered by a control mother, respectively. The results showed that offspring fostered by depressive mothers presented significant depressive behaviors. Meanwhile, depressive mothers engaged in more grooming during the light cycle, but less off-the-pup behavior during the dark phase. In conclusion, offspring exposed to a postnatal depressive maternal environment developed a depressive-like behavior. Contrarily, postpartum maternal behaviors play an essential role, which might determine the outcome of the next generation. Furthermore, the appropriate timing of postpartum maternal caring sequences, which might eliminate prenatal stressful influences, was recognized and might be a promising approach for reducing children's predisposition to mental disorders in their life time.

Social threat, fronto-cingulate-limbic morphometry, and symptom course in depressed adolescents: a longitudinal investigation

BACKGROUND

Psychosocial stressors characterized by social threat, such as interpersonal loss and social rejection, are associated with depression in adolescents. Few studies, however, have examined whether social threat affects fronto-cingulate-limbic systems implicated in adolescent depression.

METHODS

We assessed lifetime stressor severity across several domains using the Stress and Adversity Inventory (STRAIN) in 57 depressed adolescents (16.15 ± 1.32 years, 34 females), and examined whether the severity of social threat and non-social threat stressors was associated with gray matter volumes (GMVs) in the anterior cingulate cortex (ACC), amygdala, hippocampus, and nucleus accumbens (NAcc). We also examined how lifetime social threat severity and GMVs in these regions related to depressive symptoms at baseline and over 9 months.

RESULTS

General stressor severity was related to greater depression severity at baseline and over 9 months. Moreover, greater severity of social threat (but not non-social threat) stressors was associated with smaller bilateral amygdala and NAcc GMVs, and smaller bilateral surface areas of caudal and rostral ACC (all pFDR ⩽ 0.048). However, neither social threat nor non-social threat stressor severity was related to hippocampal GMVs (all pFDR ⩾ 0.318). All fronto-cingulate-limbic structures that were associated with the severity of social threat were negatively associated with greater depression severity over 9 months (all pFDR ⩽ 0.014). Post-hoc analyses suggested that gray matter morphometry of bilateral amygdala, NAcc, and rostral and caudal ACC mediated the association between social threat and depression severity in adolescents over 9 months (all pFDR < 0.048).

CONCLUSIONS

Social threat specifically affects fronto-cingulate-limbic pathways that contribute to the maintenance of depression in adolescents.

Perceived adversity and psychological distress in refugee married couples resettling in the United States

BACKGROUND

Syrian and Iraqi refugees are a growing segment of the U.S. population, and although exposure to war and violence has been linked to psychological distress in individual refugees, few studies have examined the distress in married couples.

METHODS

Using a cross-sectional design, a convenience sample of 101 Syrian and Iraqi refugee couples was recruited from a community agency. The purpose of this study was to (1) examine the relationships between perceived adversity and psychological distress (PTSD, anxiety, and depressive symptoms) among individual study participants; and (2) determine whether these relationships were correlated to their spouses' perceived adversity and psychological distress.

RESULTS

The bivariate correlation analysis showed strong positive correlations between PTSD and depression/anxiety for wives (r = .79; p < .001) and for husbands (r = .74; p < .001). There were also low- to mid-range positive cross-associations between husbands' and wives' PTSD (r = .34; p = .001) and depression/anxiety (r = .43; p < .001). Finally, we found a significant positive association between husbands' and wives' perception of adversity (r = .44; p < .001). Interestingly, the husbands' perception of adversity was positively associated with their PTSD (r = .30; p = .02) and depression/ anxiety scores (r = .26; p = .04) as well as with their wives' depression/ anxiety scores (r = .23; p = .08). In contrast, the wives' perception of adversity was not associated with either their own or their spouses' psychological distress.

CONCLUSION

Our findings suggest that war, trauma, and stress of migration impact the couple as a unit, possibly due to shared experiences, and the impact of one partner's stress on the other. Addressing these perceptions and personal interpretations of the adverse experiences via cognitive therapy approaches could help reduce not only stress in the individual but also that of their partner.

Interpersonal early adversity demonstrates dissimilarity from early socioeconomic disadvantage in the course of human brain development: A meta-analysis

It has been established that early-life adversity impacts brain development, but the role of development itself has largely been ignored. We take a developmentally-sensitive approach to examine the neurodevelopmental sequelae of early adversity in a preregistered meta-analysis of 27,234 youth (birth to 18-years-old), providing the largest group of adversity-exposed youth to date. Findings demonstrate that early-life adversity does not have an ontogenetically uniform impact on brain volumes, but instead exhibits age-, experience-, and region-specific associations. Relative to non-exposed comparisons, interpersonal early adversity (e.g., family-based maltreatment) was associated with initially larger volumes in frontolimbic regions until ∼10-years-old, after which these exposures were linked to increasingly smaller volumes. By contrast, socioeconomic disadvantage (e.g., poverty) was associated with smaller volumes in temporal-limbic regions in childhood, which were attenuated at older ages. These findings advance ongoing debates regarding why, when, and how early-life adversity shapes later neural outcomes.

Adolescent neurodevelopment and psychopathology: The interplay between adversity exposure and genetic risk for accelerated brain ageing

In adulthood, stress exposure and genetic risk heighten psychological vulnerability by accelerating neurobiological senescence. To investigate whether molecular and brain network maturation processes play a similar role in adolescence, we analysed genetic, as well as longitudinal task neuroimaging (inhibitory control, incentive processing) and early life adversity (i.e., material deprivation, violence) data from the Adolescent Brain and Cognitive Development study (N = 980, age range: 9-13 years). Genetic risk was estimated separately for Major Depressive Disorder (MDD) and Alzheimer's Disease (AD), two pathologies linked to stress exposure and allegedly sharing a causal connection (MDD-to-AD). Adversity and genetic risk for MDD/AD jointly predicted functional network segregation patterns suggestive of accelerated (GABA-linked) visual/attentional, but delayed (dopamine [D2]/glutamate [GLU5R]-linked) somatomotor/association system development. A positive relationship between brain maturation and psychopathology emerged only among the less vulnerable adolescents, thereby implying that normatively maladaptive neurodevelopmental alterations could foster adjustment among the more exposed and genetically more stress susceptible youths. Transcriptomic analyses suggested that sensitivity to stress may underpin the joint neurodevelopmental effect of adversity and genetic risk for MDD/AD, in line with the proposed role of negative emotionality as a precursor to AD, likely to account for the alleged causal impact of MDD on dementia onset.

Life stress influences the relationship between sex hormone fluctuation and affective symptoms in peripubertal female adolescents

Female adolescents have a greatly increased risk of depression starting at puberty, which continues throughout the reproductive lifespan. Sex hormone fluctuation has been highlighted as a key proximal precipitating factor in the development of mood disorders tied to reproductive events; however, hormone-induced affective state change is poorly understood in the pubertal transition. The present study investigated the impact of recent stressful life events on the relationship between sex hormone change and affective symptoms in peripubertal female participants. Thirty-five peripubertal participants (ages 11-14, premenarchal, or within 1 year of menarche) completed an assessment of stressful life events, and provided weekly salivary hormone collections [estrone, testosterone, dehydroepiandrosterone (DHEA)] and mood assessments for 8 weeks. Linear mixed models tested whether stressful life events provided a context in which within-person changes in hormones predicted weekly affective symptoms. Results indicated that exposure to stressful life events proximal to the pubertal transition influenced the directional effects of hormone change on affective symptoms. Specifically, greater affective symptoms were associated with increases in hormones in a high stress context and decreases in hormones in a low stress context. These findings provide support for stress-related hormone sensitivity as a diathesis for precipitating affective symptoms in the presence of pronounced peripubertal hormone flux.

Neurochemical mechanisms of deep brain stimulation for depression in animal models

Deep brain stimulation (DBS) has emerged as a neuromodulation therapy for treatment-resistant depression, but its actual efficacy and mechanisms of action are still unclear. Changes in neurochemical transmission are important mechanisms of antidepressant therapies. Here, we review the preclinical DBS literature reporting behavioural and neurochemical data associated with its antidepressant-like effects. The most commonly studied target in preclinical models was the ventromedial prefrontal cortex (vmPFC). In rodents, DBS delivered to this target induced serotonin (5-HT) release and increased 5-HT1_B receptor expression. The antidepressant-like effects of vmPFC DBS seemed to be independent of the serotonin transporter and potentially mediated by the direct modulation of prefrontal projections to the raphe. Adenosinergic and glutamatergic transmission might have also play a role. Medial forebrain bundle (MFB) DBS increased dopamine levels and reduced D2 receptor expression, whereas nucleus accumbens (NAcc), and lateral habenula (LHb) stimulation increased catecholamine levels in different brain regions. In rodents, subthalamic nucleus (STN) DBS induced robust depression-like responses associated with a reduction in serotonergic transmission, as revealed by a decrease in serotonin release. Some of these effects seemed to be mediated by 5HT1_A receptors. In conclusion, the antidepressant-like effects of DBS in preclinical models have been well documented in multiple targets. Though variable mechanisms have been proposed, DBS-induced acute and long-term changes in neurochemical substrates seem to play an important role in the antidepressant-like effects of this therapy.

Longitudinal association of allostatic load with depressive symptoms among urban adults: Healthy Aging in Neighborhoods of Diversity across the Life Span study

BACKGROUND

Evidence suggests that lifetime exposure to stressful life events and chronic stressors may be linked to geriatric depression. Allostatic load (AL) is considered a mediator of the stress-health relationship and has been linked to psychosocial factors reflecting health disparities. The purpose of this study was to examine the longitudinal associations of AL with depressive symptoms scores among urban adults, before and after stratifying by sex and race.

METHODS

Secondary analyses were performed using Visit 1 (2004-2009), Visit 2 (2009-2013) and Visit 3 (2013-2017) data collected on 2298 Healthy Aging in Neighborhoods of Diversity across the Life Span study participants (baseline age: 30-64 y). AL at Visit 1 (ALv1) and z-transformed probability of higher AL trajectory (ALtraj) between Visits 1 and 3 were calculated using cardiovascular, metabolic and inflammatory risk indicators. The 20-item Center for Epidemiologic Studies Depression (CES-D) scale was used to calculate total and domain-specific depressive symptoms scores. Mixed-effects linear models controlled for socio-demographic, lifestyle and health characteristics.

RESULTS

In fully adjusted models, a positive cross-sectional relationship was observed between ALv1 and "somatic complaints" depressive symptoms (β = 0.21, P = 0.006) score at Visit 1, whereas ALtraj was associated with increasing depressive symptoms score (β = 0.086, P = 0.003) between Visits 1 and 3. An inverse relationship was observed between ALtraj and "positive affect" depressive symptoms score at Visit 1 among women (β = -0.31, P < 0.0001) and White adults (β = -0.32, P = 0.004). Among women, ALtraj was also positively related to change in "somatic complaints" depressive symptoms score between Visits 1 and 3 (β = 0.043, P = 0.020).

CONCLUSIONS

Among urban adults, AL may be associated with "somatic complaints" depressive symptoms at baseline. Higher AL trajectories may predict increasing depressive symptoms (overall) and increasing "somatic complaints" depressive symptoms (among women). A higher AL trajectory may be associated with lower "positive affect" depressive symptoms at baseline among women and White adults only.

Early life adversity across different cell- types in the brain

Early life adversity (ELA)- which includes physical, psychological, emotional, and sexual abuse is one of the most common predictors to diverse psychopathologies later in adulthood. As ELA has a lasting impact on the brain at a developmental stage, recent findings from the field highlighted the specific contributions of different cell types to ELA and their association with long lasting consequences. In this review we will gather recent findings describing morphological, transcriptional and epigenetic alterations within neurons, glia and perineuronal nets and their associated cellular subpopulation. The findings reviewed and summarized here highlight important mechanisms underlying ELA and point to therapeutic approaches for ELA and related psychopathologies later in life.

The body keeps the score: The neurobiological profile of traumatized adolescents

Trauma-related disorders are debilitating psychiatric conditions that affect people who have directly or indirectly witnessed adversities. Experiencing multiple types of traumas appears to be common during childhood, and even more so during adolescence. Dramatic brain/body transformations occurring during adolescence may provide a highly responsive substrate to external stimuli and lead to trauma-related vulnerability conditions, such as internalizing (anxiety, depression, anhedonia, withdrawal) and externalizing (aggression, delinquency, conduct disorders) problems. Analyzing relations among neuronal, endocrine, immune, and biochemical signatures of trauma and internalizing and externalizing behaviors, including the role of personality traits in shaping these conducts, this review highlights that the marked effects of traumatic experience on the brain/body involve changes at nearly every level of analysis, from brain structure, function and connectivity to endocrine and immune systems, from gene expression (including in the gut) to the development of personality.

Overlapping brain correlates of superior cognition among children at genetic risk for Alzheimer's disease and/or major depressive disorder

Early life adversity (ELA) tends to accelerate neurobiological ageing, which, in turn, is thought to heighten vulnerability to both major depressive disorder (MDD) and Alzheimer's disease (AD). The two conditions are putatively related, with MDD representing either a risk factor or early symptom of AD. Given the substantial environmental susceptibility of both disorders, timely identification of their neurocognitive markers could facilitate interventions to prevent clinical onset. To this end, we analysed multimodal data from the Adolescent Brain and Cognitive Development study (ages 9-10 years). To disentangle genetic from correlated genetic-environmental influences, while also probing gene-adversity interactions, we compared adoptees, a group generally exposed to substantial ELA, with children raised by their biological families via genetic risk scores (GRS) from genome-wide association studies. AD and MDD GRSs predicted overlapping and widespread neurodevelopmental alterations associated with superior fluid cognition. Specifically, among adoptees only, greater AD GRS were related to accelerated structural maturation (i.e., cortical thinning) and higher MDD GRS were linked to delayed functional neurodevelopment, as reflected in compensatory brain activation on an inhibitory control task. Our study identifies compensatory mechanisms linked to MDD risk and highlights the potential cognitive benefits of accelerated maturation linked to AD vulnerability in late childhood.

Resilience to social defeat stress in adolescent male mice

Adverse social experiences during adolescence are associated with the appearance of mental illness in adulthood. Social defeat (SD) is an ethologically valid murine model to study the consequences of social stress. In adolescent mice, SD induces depressive-like behaviors, increased anxiety and potentiates the reinforcing effects of cocaine and alcohol. However, not all mice exposed to SD will be susceptible to these effects. Adult mice resilient to the effects of SD show a consistent phenotype being resilient to depressive-like behaviors and to the increase in cocaine and alcohol consumption. The aim of the present study was to characterize the resilient phenotype to depressive-like behaviors and increase cocaine and ethanol rewarding effects of mice socially defeated during adolescence. To that end, adolescent mice were exposed to repeated SD, and 24 h after the last encounter, they underwent a social interaction test (SIT) in order to evaluate depressive-like behaviors. Cocaine-induced reward conditioning and ethanol intake was evaluated in two different sets of mice 3 weeks after the last SD using cocaine-induced conditioned place preference (CPP) and oral ethanol self-administration (SA). The neuroinflammation response was measured at the end of the experimental procedure by measuring striatal and cortical levels of IL-6 and CX3CL1. The results confirmed that a comparable percentage of adolescent mice develop resilience to depressive-like behaviors to that observed in adult mice. However, increased anxiety was more severe in resilient mice. Likewise, an increased preference for an ineffective dose of cocaine and an increased ethanol consumption was observed in resilient mice compared to controls. The increase in IL-6 and CX3CL1 was mainly observed in the striatum of susceptible mice compared to that of control mice. Our results confirm that, contrary to prior assumptions in adults, responses to SD stress are more complex and singular in adolescents, and caution should be taken for the correct interpretation and translation of those phenotypes.

On the Application of Developmental Cognitive Neuroscience in Educational Environments

The paper overviews components of neurologic processing efficiencies to develop innovative methodologies and thinking to school-based applications and changes in educational leadership based on sound findings in the cognitive neurosciences applied to schools and learners. Systems science can allow us to better manage classroom-based learning and instruction on the basis of relatively easily evaluated efficiencies or inefficiencies and optimization instead of simply examining achievement. "Medicalizing" the learning process with concepts such as "learning disability" or employing grading methods such as pass-fail does little to aid in understanding the processes that learners employ to acquire, integrate, remember, and apply information learned. The paper endeavors to overview and provided reference to tools that can be employed that allow a better focus on nervous system-based strategic approaches to classroom learning.

Dimensions of childhood adversity differentially affect biological aging in major depression

Adverse childhood experiences have been consistently linked with physical and mental health disorders in adulthood that may be mediated, in part, via the effects of such exposures on biological aging. Using recently developed "epigenetic clocks", which provide an estimate of biological age, several studies have demonstrated a link between the cumulative exposure to childhood adversities and accelerated epigenetic aging. However, not all childhood adversities are equivalent and less is known about how distinct dimensions of childhood adversity relate to epigenetic aging metrics. Using two measures of childhood adversity exposure, we assess how the dimensions of Maltreatment and Household Dysfunction relate to epigenetic aging using two "second-generation" clocks, GrimAge and PhenoAge, in a cohort of unmedicated somatically healthy adults with moderate to severe major depression (n = 82). Our results demonstrate that the dimension of Maltreatment is associated with epigenetic age acceleration (EAA) using the PhenoAge but not the GrimAge clock. This association was observed using both the Childhood Trauma questionnaire (CTQ; β = 0.272, p = 0.013) and the Adverse Childhood Experiences (ACEs) questionnaire (β = 0.307, p = 0.005) and remained significant when adjusting for exposure to the dimension of Household Dysfunction (β = 0.322, p = 0.009). In contrast, the dimension of Household Dysfunction is associated with epigenetic age deceleration (β = -0.194, p = 0.083) which achieved significance after adjusting for exposure to the dimension of Maltreatment (β = -0.304, p = 0.022). This study is the first to investigate these effects among individuals with Major Depressive Disorder and suggests that these dimensions of adversity may be associated with disease via distinct biological mechanisms.

Associations of depression and regional brain structure across the adult lifespan: Pooled analyses of six population-based and two clinical cohort studies in the European Lifebrain consortium

OBJECTIVE

Major depressive disorder has been associated with lower prefrontal thickness and hippocampal volume, but it is unknown whether this association also holds for depressive symptoms in the general population. We investigated associations of depressive symptoms and depression status with brain structures across population-based and patient-control cohorts, and explored whether these associations are similar over the lifespan and across sexes.

METHODS

We included 3,447 participants aged 18-89 years from six population-based and two clinical patient-control cohorts of the European Lifebrain consortium. Cross-sectional meta-analyses using individual person data were performed for associations of depressive symptoms and depression status with FreeSurfer-derived thickness of bilateral rostral anterior cingulate cortex (rACC) and medial orbitofrontal cortex (mOFC), and hippocampal and total grey matter volume (GMV), separately for population-based and clinical cohorts.

RESULTS

Across patient-control cohorts, depressive symptoms and presence of mild-to-severe depression were associated with lower mOFC thickness (r_symptoms = -0.15/ r_status = -0.22), rACC thickness (r_symptoms = -0.20/ r_status = -0.25), hippocampal volume (r_symptoms = -0.13/ r_status = 0.13) and total GMV (r_symptoms = -0.21/ r_status = -0.25). Effect sizes were slightly larger for presence of moderate-to-severe depression. Associations were similar across age groups and sex. Across population-based cohorts, no associations between depression and brain structures were observed.

CONCLUSIONS

Fitting with previous meta-analyses, depressive symptoms and depression status were associated with lower mOFC, rACC thickness, and hippocampal and total grey matter volume in clinical patient-control cohorts, although effect sizes were small. The absence of consistent associations in population-based cohorts with mostly mild depressive symptoms, suggests that significantly lower thickness and volume of the studied brain structures are only detectable in clinical populations with more severe depressive symptoms.

RPS6KA5 methylation predict response to 6-week treatment for adolescent MDD patients

OBJECTIVE

We aimed to investigate the effect of differentially methylated genes and chronic childhood stress on the development of depressive symptoms in Chinese adolescents, as well as to test whether methylation at baseline can be used as a predictor of remission at follow-up after six weeks of treatment.

METHODS

After recruiting 87 MDD patients and 53 healthy controls, we compared demographic and baseline clinical characteristics. The Childhood Chronic Stress Questionnaire was used to assess stress caused by early-life events. MDD patients underwent six weeks of treatment, and response to treatment was assessed using the Beck Depression Inventory-II. In addition, four MDD patients and five controls were randomly chosen for genome-wide methylation analysis.

RESULTS

The gene RPS6KA5 showed significant methylation differences between the two groups. Severity of chronic childhood stress was significantly associated with increased risk of depression in adolescents, but not with treatment response. Baseline RPS6KA5 methylation can predict remission after six weeks of treatment. We did not observe any interaction between RPS6KA5 methylation and chronic childhood stress.

CONCLUSIONS

Our results suggest that RPS6KA5 methylation can be used as a predictor of response to treatment in adolescent MDD patients. Here we offer new evidence for the role of epigenetics in early response to treatment of depression.

TRIAL REGISTRATION

ChiCTR, ChiCTR2000033402, 31/05/2020, http://www.chictr.org.cn/index.aspx.

Effects of RhoA on depression-like behavior in prenatally stressed offspring rats

Depression is a common mental disease that can lead to suicide when severe. Exposure to prenatal stress (PS) can lead to depression-like behavior in offspring, but the mechanism is unclear. RhoA (Ras homology family member A) plays an important role in stress-induced changes in synaptic plasticity, participating in the development of depression by activating the downstream effector ROCK (Rho-associated protein kinase). This study explored the influence in the expression of RhoA and downstream molecules ROCK1/2 in prenatally stressed rats, and the effect of RhoA inhibitor simvastatin on depression-like behavior induced by PS. Depression-like behavior in offspring was detected by sucrose preference test, forced swimming test, and open-field test. The mRNA and protein expression of RhoA and ROCK1/2 in the hippocampus and prefrontal cortex of offspring rats were detected by qRT-PCR and western blotting, respectively. Our results showed that PS causes depression-like behavior in offspring rats, associated with elevated expression of RhoA, ROCK1/2 in the hippocampus and prefrontal cortex. After administration of simvastatin to PS rats, the expression of RhoA and ROCK2 was significantly reduced, alleviating depression-like behavior. Our study demonstrated that RhoA participates in the depression-like behavior in prenatally stressed offspring rats, which may be a potential target for antidepressant therapy.

Childhood Threat Is Associated With Lower Resting-State Connectivity Within a Central Visceral Network

Childhood adversity is associated with altered or dysregulated stress reactivity; these altered patterns of physiological functioning persist into adulthood. Evidence from both preclinical animal models and human neuroimaging studies indicates that early life experience differentially influences stressor-evoked activity within central visceral neural circuits proximally involved in the control of stress responses, including the subgenual anterior cingulate cortex (sgACC), paraventricular nucleus of the hypothalamus (PVN), bed nucleus of the stria terminalis (BNST) and amygdala. However, the relationship between childhood adversity and the resting-state connectivity of this central visceral network remains unclear. To this end, we examined relationships between childhood threat and childhood socioeconomic deprivation, the resting-state connectivity between our regions of interest (ROIs), and affective symptom severity and diagnoses. We recruited a transdiagnostic sample of young adult males and females (n = 100; mean age = 27.28, SD = 3.99; 59 females) with a full distribution of maltreatment history and symptom severity across multiple affective disorders. Resting-state data were acquired using a 7.2-min functional magnetic resonance imaging (fMRI) sequence; noted ROIs were applied as masks to determine ROI-to-ROI connectivity. Threat was determined by measures of childhood traumatic events and abuse. Socioeconomic deprivation (SED) was determined by a measure of childhood socioeconomic status (parental education level). Covarying for age, race and sex, greater childhood threat was significantly associated with lower BNST-PVN, amygdala-sgACC and PVN-sgACC connectivity. No significant relationships were found between SED and resting-state connectivity. BNST-PVN connectivity was associated with the number of lifetime affective diagnoses. Exposure to threat during early development may entrain altered patterns of resting-state connectivity between these stress-related ROIs in ways that contribute to dysregulated neural and physiological responses to stress and subsequent affective psychopathology.

Consequences of Inadequate Caregiving for Children's Attachment, Neurobiological Development, and Adaptive Functioning

Given that human infants are almost fully reliant on caregivers for survival, the presence of parents who provide sensitive, responsive care support infants and young children in developing the foundation for optimal biological functioning. Conversely, when parents are unavailable or insensitive, there are consequences for infants' and children's attachment and neurobiological development. In this paper, we describe effects of inadequate parenting on children's neurobiological and behavioral development, with a focus on developing capacities for executive functioning, emotion regulation, and other important cognitive-affective processes. Most prior research has examined correlational associations among these constructs. Given that interventions tested through randomized clinical trials allow for causal inferences, we review longitudinal intervention effects on children's biobehavioral and cognitive-affective outcomes. In particular, we provide an overview of the Bucharest Early Intervention Project, a study in which children were randomized to continue in orphanage care (typically the most extreme condition of privation) or were placed into the homes of trained, supported foster parents. We also discuss findings regarding Attachment and Biobehavioral Catch-up, an intervention enhancing sensitivity among high-risk parents. We conclude by suggesting future directions for research in this area.

Early Life Stress and Brain Plasticity: From Alterations of Brain Morphology to Development of Psychopathology

Advances in our understanding of the genetics of mental disorders (MD) have contributed to a better understanding of their pathophysiology. Nonetheless, several questions and doubts remain. Recent research has focused on the role of the environment in developing mental disorders, and the advent of neuroscientific methodologies has opened up new avenues of inquiry. However, the mechanism by which childhood stress affects neurodevelopment via mechanisms, such as gene-environment interactions and epigenetic regulation leading to diseases in adulthood, is unclear. This paper aims to review the evidence on the role of early life stress and parental psychopathology in the pathophysiology and clinical expression of MD. Methodology: The study will conduct a comprehensive systematic review using medical search terms (MeSH). Electronic searches for published studies will be performed using the MEDLINE (PubMed), EMBASE, Scopus, PsychINFO, Web of Science, and Google Scholar databases. We will look for research on the neuroplasticity effects of early life stress on development and review articles that evaluate cognitive functions and the development of psychopathology and MD. Before identifying full-text articles, several studies will be filtered based on titles, abstracts, keywords, and synonyms. Publications to be included in the review will be assessed for quality and consistency before inclusion. Data will be extracted independently and duplicated by two authors from each eligible study to ensure consistency between reviews. All databases will be searched from inception until July 2021 and will be limited to human studies. The search will be limited only to publication in the English language and any publication that can be converted to English. Discussion and Conclusions: The findings of this review will meticulously articulate the effects of childhood adversity, such as ELS and parental psychopathology on cognitive development and neuroplasticity.