The effects of socio-affective environment

This chapter focuses on new concepts and new paradigms shedding light on the complex issue of socioenvironmental factors that affect the psychologic development of the child. Longitudinal controlled studies have sorted out "what leads to what under which circumstances," adding to the heuristic value of the addition of risks and of the Bronfenbrenner's ecologic model of development and disentangling the socioeconomic status (SES) from poverty. We emphasize the importance of taking attachment styles and attachment disorganization into account for a better understanding of both normal development and early psychopathology. Intervention studies demonstrate the real life effect of the gene-environment interaction with or without epigenetic processes. Thus, this chapter deals with paradigmatic situations as ADS, Prader-Willi, or prematurity as they allow us to learn more about early development and epigenetic influences.

The development of stress reactivity and regulation during human development

Adverse experiences during childhood can have long-lasting impacts on physical and mental health. At the heart of most theories of how these effects are transduced into health impacts is the activity of stress-mediating systems, most notably the hypothalamic-pituitary-adrenocortical (HPA) axis. Here we review the anatomy and physiology of the axis, models of stress and development, the development of the axis prenatally through adolescence, the role of experience and sensitive periods in shaping its regulation, the social regulation of the axis at different points in development, and finally conclude with suggestions for future research. We conclude that it is clear that early adversity sculpts the stress system, but we do not understand which dimensions have the most impact and at what points in early development. It is equally clear that secure attachment relationships buffer the developing stress system; however, the mechanisms of social buffering and how these may change with development are not yet clear. Another critical issue that is not understood is when and for whom adversity will result in hypo- vs hyperactivity of stress-mediating systems. These and other issues are important for advancing our understanding of how early adversity "gets under the skin" and shapes human physical and mental health.

Sensitive Periods for the Effect of Childhood Adversity on DNA Methylation: Results From a Prospective, Longitudinal Study

BACKGROUND

Exposure to early-life adversity is known to predict DNA methylation (DNAm) patterns that may be related to psychiatric risk. However, few studies have investigated whether adversity has time-dependent effects based on the age at exposure.

METHODS

Using a two-stage structured life course modeling approach, we tested the hypothesis that there are sensitive periods when adversity induces greater DNAm changes. We tested this hypothesis in relation to two alternatives: an accumulation hypothesis, in which the effect of adversity increases with the number of occasions exposed, regardless of timing; and a recency model, in which the effect of adversity is stronger for more proximal events. Data came from the Accessible Resource for Integrated Epigenomic Studies, a subsample of mother-child pairs from the Avon Longitudinal Study of Parents and Children (n = 691-774).

RESULTS

After covariate adjustment and multiple testing correction, we identified 38 CpG sites that were differentially methylated at 7 years of age following exposure to adversity. Most loci (n = 35) were predicted by the timing of adversity, namely exposures before 3 years of age. Neither the accumulation nor recency of the adversity explained considerable variability in DNAm. A standard epigenome-wide association study of lifetime exposure (vs. no exposure) failed to detect these associations.

CONCLUSIONS

The developmental timing of adversity explains more variability in DNAm than the accumulation or recency of exposure. Very early childhood appears to be a sensitive period when exposure to adversity predicts differential DNAm patterns. Classification of individuals as exposed versus unexposed to early-life adversity may dilute observed effects.

Developmental Contributors to Trauma Response: The Importance of Sensitive Periods, Early Environment, and Sex Differences

This review considers early factors that interact with development to contribute to later trauma responses, including developmental sensitive periods, the effects of early environment, and the emergence of sex differences. We also describe development of neural substrates that have been associated with posttraumatic stress disorder and specifically focus on fear behavior and circuitry. Emerging evidence suggests that there may be developmental shifts around age 10 in these underlying circuits that may contribute to vulnerability. We also discuss age-related changes in the importance of caregiver availability as positive buffering factors. Hormonal changes later in development with onset during puberty appear to further shape development trajectories toward risk or resilience. We highlight these recent findings as well as the great need for further longitudinal research from middle childhood through early adulthood.

Neighborhood disadvantage across the transition from adolescence to adulthood and risk of metabolic syndrome

This study investigates the association between neighborhood disadvantage from adolescence to young adulthood and metabolic syndrome using a life course epidemiology framework. Data from the United States-based National Longitudinal Study of Adolescent to Adult Health (n = 9500) and a structural equation modeling approach were used to test neighborhood disadvantage across adolescence, emerging adulthood, and young adulthood in relation to metabolic syndrome. Adolescent neighborhood disadvantage was directly associated with metabolic syndrome in young adulthood. Evidence supporting an indirect association between adolescent neighborhood disadvantage and adult metabolic syndrome was not supported. Efforts to improve cardiometabolic health may benefit from strategies earlier in life.

Are there sensitive neighbourhood effect periods during the life course on midlife health and wellbeing?

Since the turn of the century there has been an explosion in the number of epidemiological studies that have analysed neighbourhood effects on health and wellbeing. The vast majority of these studies are cross-sectional in nature and assume that a contemporaneous place of residence captures a meaningful neighbourhood effect. Over the same time frame, social epidemiology has focussed increasingly on life course effects. This paper aims to bring these two areas of study together and tests whether there a certain ages during the life course when neighbourhoods are more important for our health and wellbeing than others. We use two British birth cohort studies (1958 National Child Development Study and British Cohort Study 1970) each comprising approximately 6,000 sample members at midlife linked to historic census measures used to derived Townsend neighbourhood deprivation scores over the life course. We find little evidence to support our hypothesis that adolescence is a key period of neighbourhood effect, rather we find late-early-adulthood neighbourhood deprivation and midlife neighbourhood deprivation are more strongly related to mid-life health and wellbeing. We are not able to conclude whether these effects are causal and encourage further investigation of selection mechanisms into neighbourhoods and mediation throughout the life course using our newly created dataset.

Age-dependent differences in the impact of paediatric traumatic brain injury on executive functions: A prospective study using susceptibility-weighted imaging

Childhood and adolescence represent sensitive developmental periods for brain networks implicated in a range of complex skills, including executive functions (EF; inhibitory control, working memory, and cognitive flexibility). As a consequence, these skills may be particularly vulnerable to injuries sustained during these sensitive developmental periods. The present study investigated 1) whether age at injury differentially affects EF 6 months and 2 years after TBI in children aged 5-15 years, and 2) whether the association between brain lesions and EF depend on age at injury. Children with TBI (n = 105) were categorized into four age-at-injury groups based on previous studies and proposed timing of cerebral maturational spurts: early childhood (5-6 years, n = 14), middle childhood (7-9 years, n = 24), late childhood (10-12 years, n = 52), and adolescence (13-15 years, n = 15). EF were assessed with performance-based tasks and a parent-report of everyday EF. TBI patients' EF scores 6 months and 2 years post-injury were compared to those of typically developing (TD) controls (n = 42). Brain lesions were identified using susceptibility weighted imaging (SWI). Results indicated that inhibitory control performance 2 years post-injury was differentially affected by the impact of TBI depending on age at injury. Follow-up analyses did not reveal significant differences within the age groups, preventing drawing strong conclusions regarding the contribution of age at injury to EF outcome after TBI. Tentatively, large effect sizes suggest that vulnerability is most apparent in early childhood and adolescence. Everyday inhibitory control behaviour was worse for children with TBI than TD children across childhood and adolescence at the 2-year assessment. There was no evidence for impairment in working memory or cognitive flexibility after TBI at the group level. Given small group sizes, findings from analyses into correlations between EF and SWI lesions should be interpreted with caution. Extent, number and volume of brain lesions correlated with adolescent everyday EF behaviour 6 months post-injury. Taken together, the results emphasize the need for long-term follow-up after paediatric TBI during sensitive developmental periods given negative outcomes 2-year post injury. Inhibitory control seems to be particular vulnerable to the impact of TBI. Findings of associations between EF and SWI lesions need to be replicated with larger samples.

Childhood trauma and the enduring consequences of forcibly separating children from parents at the United States border

Forcible separation and detention of children from parents seeking asylum in the United States has been decried as immoral and halted by court order. Babies and children have been separated and transported to facilities sometimes many miles away. Limited data on forced detention of unaccompanied minors reveal high incidence of posttraumatic stress, anxiety disorders, depression, aggression, and suicidal ideation. These consequences will be magnified in youths forcibly separated from their parents, particularly younger children who depend on attachment bonds for self-regulation and resilience. Studies exploring the neuropsychiatric consequences of traumatic stress have revealed consistent effects of early life stress on brain structure, function and connectivity, and the identification of sensitive periods, which occur throughout childhood when specific regions and pathways are strongly influenced by adversity. Studies of epigenetics, inflammation and allostatic load are similarly enhancing our awareness of the molecular mechanisms underpinning the long-term consequences of traumatic stress. We must consider effects on the developing brain, mind and body to appreciate the long-term consequences of policies that force separation and detention of children.

Exposure to childhood adversity and deficits in emotion recognition: results from a large, population-based sample

BACKGROUND

Emotion recognition skills are essential for social communication. Deficits in these skills have been implicated in mental disorders. Prior studies of clinical and high-risk samples have consistently shown that children exposed to adversity are more likely than their unexposed peers to have emotion recognition skills deficits. However, only one population-based study has examined this association.

METHODS

We analyzed data from children participating in the Avon Longitudinal Study of Parents and Children, a prospective birth cohort (n = 6,506). We examined the association between eight adversities, assessed repeatedly from birth to age 8 (caregiver physical or emotional abuse; sexual or physical abuse; maternal psychopathology; one adult in the household; family instability; financial stress; parent legal problems; neighborhood disadvantage) and the ability to recognize facial displays of emotion measured using the faces subtest of the Diagnostic Assessment of Non-Verbal Accuracy (DANVA) at age 8.5 years. In addition to examining the role of exposure (vs. nonexposure) to each type of adversity, we also evaluated the role of the timing, duration, and recency of each adversity using a Least Angle Regression variable selection procedure.

RESULTS

Over three-quarters of the sample experienced at least one adversity. We found no evidence to support an association between emotion recognition deficits and previous exposure to adversity, either in terms of total lifetime exposure, timing, duration, or recency, or when stratifying by sex.

CONCLUSIONS

Results from the largest population-based sample suggest that even extreme forms of adversity are unrelated to emotion recognition deficits as measured by the DANVA, suggesting the possible immutability of emotion recognition in the general population. These findings emphasize the importance of population-based studies to generate generalizable results.

Cortical correlates of amblyopia

There are many levels of disorder in amblyopic vision, from basic acuity and contrast sensitivity loss to abnormal binocular vision and global perception of motion and form. Amblyopia treatment via patching to restore acuity often leaves other aspects of vision deficient. The source for these additional deficits is unclear. Neural correlates of poor binocular function and acuity loss are found in V1 and V2. However, they are generally not sufficient to account for behaviorally measured vision loss. This review summarizes the known cortical correlates of visual deficits found in association with amblyopia, particularly those relevant to binocular vision and higher-order visual processing, in striate and extrastriate cortex. Recommendations for future research address open questions on the role of suppression and oculomotor abnormalities in amblyopic vision, and underexplored mechanisms such as top-down influences on information transmission in the amblyopic brain.

Developmental timing of trauma exposure and emotion dysregulation in adulthood: Are there sensitive periods when trauma is most harmful?

BACKGROUND

This study aimed to determine whether there were sensitive periods when a first exposure to trauma was most associated with emotion dysregulation symptoms in adulthood.

METHODS

Adult participants came from a public urban hospital in Atlanta, GA (n = 1944). Lifetime trauma exposure was assessed using the Traumatic Events Inventory (TEI). Multiple linear regression models were used to assess the association between the developmental timing of first trauma exposure, classified as early childhood (ages 0-5), middle childhood (ages 6-10), adolescence (ages 11-18), and adulthood (ages 19+), on adult emotion dysregulation symptoms, measured using the abbreviated Emotion Dysregulation Scale.

RESULTS

Participants exposed to trauma at any age had higher emotion dysregulation scores than their unexposed peers. However, participants first exposed to child maltreatment or interpersonal violence during middle childhood had higher emotion dysregulation scores relative to those first exposed during other developmental stages; these developmental timing differences were detected even after controlling for sociodemographic factors, exposure to other trauma, and frequency of exposure to trauma. Further, after controlling for current psychiatric symptoms, the effect of other interpersonal trauma exposure in middle childhood was diminished and first exposure to other interpersonal violence in early childhood was associated with significantly lower emotion dysregulation symptoms.

LIMITATIONS

Limitations of this study include the use of retrospective reports and absence of complete information about trauma severity or duration.

CONCLUSION

These findings should be replicated in other population-based samples with prospective designs to confirm the importance of developmental timing of trauma on later emotion dysregulation.

Do bacteria shape our development? Crosstalk between intestinal microbiota and HPA axis

The human body contains as many bacteria in the intestine as the total number of human body cells. These bacteria have a central position in human health and disease, and would also play a role in the regulation of emotions, behavior, and even higher cognitive functions. The Hypothalamic-Pituitary-Adrenal axis (HPA axis) is a major physiological stress system that produces cortisol. This hormone is involved in responding to environmental stress and also shapes many aspects of brain development. Both the HPA axis and the intestinal microbiota show rapid and profound developmental changes during the first years of life. Early environmental disturbances can affect the development of both systems. Early adversity, for example, is known to lead to later unbalances in both, as well as to psychopathological behavior and emotions. The goal of this theoretical review is to summarize current knowledge on the developmental crosstalk between the intestinal microbiota and the HPA axis, providing a basis for understanding the development and bidirectional communication between these two essential systems in human functioning.

Are There Sensitive Periods for Food Acceptance in Infancy?

PURPOSE OF REVIEW

A sensitive period in development is one in which it is easier for learning to take place; the behaviour can however still be learned at a later stage, but with more difficulty. This is in contrast to a critical period, a time at which a behaviour must be learned, and if this window of opportunity is missed, then the behaviour can never be acquired. Both might determine food acceptance in childhood.

RECENT FINDINGS

There is evidence to support the idea of a sensitive period for the introduction of tastes, a critical period for the introduction of textures and for the development of oral motor function, and a possible critical period for the introduction of new foods but only in children where there is an innate disposition to develop early and extreme disgust responses.

SUMMARY

There are both sensitive and critical periods in the acquisition of food preferences.

Adolescence Is a Sensitive Period for Housing Mobility to Influence Risky Behaviors: An Experimental Design

PURPOSE

Test whether neighborhood mobility effects on adolescent risky behaviors varies at different developmental ages and gender.

METHODS

The Moving to Opportunity (MTO) study randomly assigned volunteer families (1994-1997) to receive a Section 8 voucher to move to lower poverty neighborhoods versus a public housing control group. We tested three-way treatment, gender, and age-at-randomization interactions using intent-to-treat linear regression predicting a risky behavior index (RBI; measured in 2002, N = 2,829), defined as the fraction of 10 behaviors the youth reported (six measuring risky substance use [RSU], four measuring risky sexual behavior), and the RSU and risky sexual behavior subscales.

RESULTS

The treatment main effect on RBI was nonsignificant for girls (B = -.01, 95% confidence interval -.024 to .014) and harmful for boys (B = .03, 95% confidence interval .009 to .059; treatment-gender interaction p = .01). The treatment, gender, and age interaction was significant for RBI (p = .02) and RSU (p ≤ .001). Treatment boys 10 years or older at randomization were more likely (p < .05) than controls to exhibit RBI and RSU, whereas there was no effect of treatment for boys <10 years. There were no treatment control differences by age for girls' RBI, but girls 9+ years were less likely than girls ≤8 years to exhibit RSU (p < .05).

CONCLUSIONS

Moving families of boys aged 10 years or older with rental vouchers may have adverse consequences on risky behaviors but may be beneficial for girls' substance use. Developmental windows are different by gender for the effects of improving neighborhood contexts on adolescent risky behavior.

Is developmental timing of trauma exposure associated with depressive and post-traumatic stress disorder symptoms in adulthood?

BACKGROUND

Trauma exposure is a known risk factor for psychopathology. However, the impact of the developmental timing of exposure remains unclear. This study examined the effect of age at first trauma exposure on levels of adult depressive and posttraumatic stress disorder (PTSD) symptoms.

METHODS

Lifetime trauma exposure (including age at first exposure and frequency), current psychiatric symptoms, and sociodemographic information were collected during interviews with adults participating in a study at a public urban hospital in Atlanta, GA. Multiple linear regression models assessed the association between timing of first trauma exposure, classified as early childhood (ages 0-5), middle childhood (ages 6-10), adolescence (ages 11-18), and adulthood (ages 19+), on adult psychopathology in 2892 individuals.

RESULTS

Participants exposed to trauma (i.e., child maltreatment, other interpersonal violence, non-interpersonal violence, and other events) at any age had higher depressive and PTSD symptoms compared to their unexposed peers. However, participants first exposed to child maltreatment during early childhood had depression and PTSD symptoms that were about twice as high as those exposed during later developmental stages. This association was detected even after controlling for sociodemographic characteristics, exposure to other trauma types, and frequency of exposure. Participants first exposed during middle childhood to other interpersonal violence also had depressive symptoms scores that were about twice as high as those first exposed during adulthood.

CONCLUSIONS

Trauma exposure at different ages may differentially impact depressive and PTSD symptoms in adulthood. More detailed examination of timing of trauma exposure is warranted to aid in identifying sensitive periods in development.

A systematic review of adrenarche as a sensitive period in neurobiological development and mental health

Substantial hormonal and neurobiological changes occur during puberty, and are widely argued to render this period of life a sensitive period in terms of risk for mental health problems. However, there is a paucity of research focusing on adrenarche, the earlier phase of pubertal development. Furthermore, there is a limited understanding of the association between adrenarche and neural development during this phase of life. We systematically reviewed research examining human adrenarcheal development as operationalized by hormonal levels of DHEA and DHEA-S, in relation to indices of mental health (Systematic Review 1). We then reviewed the limited amount of literature that has examined the association between adrenarcheal development and brain structure or function (Systematic Review 2). In general, studies showed that earlier timing of adrenarche was associated with greater mental health symptoms, and there is emerging support that brain development plays a role in this relationship. However, several methodological inconsistencies were noted. We propose that future research in this area test a theoretical model of adrenarche as a sensitive period of neurobiological development, whereby timing of exposure to hormones interacts with brain development, biological sex, and psychosocial stress to influence environmental sensitivity and risk for mental health problems through adolescence.

Predicting later life health status and mortality using state-level socioeconomic characteristics in early life

Studies extending across multiple life stages promote an understanding of factors influencing health across the life span. Existing work has largely focused on individual-level rather than area-level early life determinants of health. In this study, we linked multiple data sets to examine whether early life state-level characteristics were predictive of health and mortality decades later. The sample included 143,755 U.S. employees, for whom work life claims and administrative data were linked with early life state-of-residence and mortality. We first created a "state health risk score" (SHRS) and "state mortality risk score" (SMRS) by modeling state-level contextual characteristics with health status and mortality in a randomly selected 30% of the sample (the "training set"). We then examined the association of these scores with objective health status and mortality in later life in the remaining 70% of the sample (the "test set") using multivariate linear and Cox regressions, respectively. The association between the SHRS and adult health status was β=0.14 (95%CI: 0.084, 0.20), while the hazard ratio for the SMRS was 0.96 (95%CI: 0.93, 1.00). The association between the SHRS and health was not statistically significant in older age groups at a p-level of 0.05, and there was a statistically significantly different association for health status among movers compared to stayers. This study uses a life course perspective and supports the idea of "sensitive periods" in early life that have enduring impacts on health. It adds to the literature examining populations in the U.S. where large linked data sets are infrequently available.

Sensitive periods of substance abuse: Early risk for the transition to dependence

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Early substance use dramatically increases the risk of substance use disorder (SUD).

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Although many try drugs, only a small percentage transition to SUD.

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High reactivity of reward, habit, and stress systems increase risk.

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Identification of early risk enables targeted, preventative interventions for SUD.

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Prevention must start before the sensitive adolescent period to maximize resilience.

Early adolescent substance use dramatically increases the risk of lifelong substance use disorder (SUD). An adolescent sensitive period evolved to allow the development of risk-taking traits that aid in survival; today these may manifest as a vulnerability to drugs of abuse. Early substance use interferes with ongoing neurodevelopment to induce neurobiological changes that further augment SUD risk. Although many individuals use drugs recreationally, only a small percentage transition to SUD. Current theories on the etiology of addiction can lend insights into the risk factors that increase vulnerability from early recreational use to addiction. Building on the work of others, we suggest individual risk for SUD emerges from an immature PFC combined with hyper-reactivity of reward salience, habit, and stress systems. Early identification of risk factors is critical to reducing the occurrence of SUD. We suggest preventative interventions for SUD that can be either tailored to individual risk profiles and/or implemented broadly, prior to the sensitive adolescent period, to maximize resilience to developing substance dependence. Recommendations for future research include a focus on the juvenile and adolescent periods as well as on sex differences to better understand early risk and identify the most efficacious preventions for SUD.

The organizing actions of adolescent gonadal steroid hormones on brain and behavioral development

Adolescence is a developmental period characterized by dramatic changes in cognition, risk-taking and social behavior. Although gonadal steroid hormones are well-known mediators of these behaviors in adulthood, the role gonadal steroid hormones play in shaping the adolescent brain and behavioral development has only come to light in recent years. Here we discuss the sex-specific impact of gonadal steroid hormones on the developing adolescent brain. Indeed, the effects of gonadal steroid hormones during adolescence on brain structure and behavioral outcomes differs markedly between the sexes. Research findings suggest that adolescence, like the perinatal period, is a sensitive period for the sex-specific effects of gonadal steroid hormones on brain and behavioral development. Furthermore, evidence from studies on male sexual behavior suggests that adolescence is part of a protracted postnatal sensitive period that begins perinatally and ends following adolescence. As such, the perinatal and peripubertal periods of brain and behavioral organization likely do not represent two discrete sensitive periods, but instead are the consequence of normative developmental timing of gonadal hormone secretions in males and females.

Childhood adversity and insomnia in adolescence

OBJECTIVE

The study aims to evaluate the association between exposure to childhood adversity and insomnia, with an emphasis on the role of adversity type, timing, and accumulation (i.e., the number of specific types of adversities the child reported being exposed to).

METHODS

Our analytic sample comprised 9582 adolescents from the National Comorbidity Survey Replication Adolescent Supplement (NCS-A), a nationally representative population-based sample. We examined the association between 18 different types of retrospectively reported adversities (capturing interpersonal violence, accidents and injuries, social network or witnessing events, and other adverse events) and risk of self-reported past-year insomnia. We also examined whether the age at first exposure to adversity was associated with the risk of insomnia, and whether exposure to a greater number of different types of adversities (ie, accumulation) conferred an elevated risk of insomnia. In addition, we performed a sensitivity analysis excluding adolescents with a past-year diagnosis of major depression, dysthymia, post-traumatic stress disorder (PTSD), or generalized anxiety disorder.

RESULTS

Almost one-third of adolescents reported insomnia, with a higher prevalence among girls and those from racial/ethnic minority groups. Adolescents exposed to at least one childhood adversity of any type (59.41%) were more likely than their nonexposed peers to experience insomnia (across adversities, prevalence ratios (PRs) ranged from 1.31 to 1.89). Risk of insomnia differed based on the age at first exposure to adversity as well as the type of adversity. Adolescents exposed to a greater number of different types of adversities had a higher risk of insomnia compared to those experiencing fewer adversities. These results were similar, by and large, to those obtained after excluding adolescents with at least one of the four past-year psychiatric disorders.

CONCLUSIONS

Exposure to adversity confers an elevated risk of insomnia. This association varied by type, timing, and accumulation of exposure and did not appear to be driven by psychiatric disorders. Given the well-documented physical and mental health consequences of insomnia, such findings further support the need for practitioners to screen children for exposure to childhood adversity and insomnia symptoms.

Birth weight, early life course BMI, and body size change: Chains of risk to adult inflammation?

This paper examines how body size changes over the early life course to predict high sensitivity C-reactive protein in a U.S. based sample. Using three waves of the National Longitudinal Study of Adolescent Health (Add Health), we test the chronic disease epidemiological models of fetal origins, sensitive periods, and chains of risk from birth into adulthood. Few studies link birth weight and changes in obesity status over adolescence and early adulthood to adult obesity and inflammation. Consistent with fetal origins and sensitive periods hypotheses, body size and obesity status at each developmental period, along with increasing body size between periods, are highly correlated with adult CRP. However, the predictive power of earlier life course periods is mediated by body size and body size change at later periods in a pattern consistent with the chains of risk model. Adult increases in obesity had effect sizes of nearly 0.3 sd, and effect sizes from overweight to the largest obesity categories were between 0.3 and 1 sd. There was also evidence that risk can be offset by weight loss, which suggests that interventions can reduce inflammation and cardiovascular risk, that females are more sensitive to body size changes, and that body size trajectories over the early life course account for African American- and Hispanic-white disparities in adult inflammation.

Does developmental timing of exposure to child maltreatment predict memory performance in adulthood? Results from a large, population-based sample

Although maltreatment is a known risk factor for multiple adverse outcomes across the lifespan, its effects on cognitive development, especially memory, are poorly understood. Using data from a large, nationally representative sample of young adults (Add Health), we examined the effects of physical and sexual abuse on working and short-term memory in adulthood. We examined the association between exposure to maltreatment as well as its timing of first onset after adjusting for covariates. Of our sample, 16.50% of respondents were exposed to physical abuse and 4.36% to sexual abuse by age 17. An analysis comparing unexposed respondents to those exposed to physical or sexual abuse did not yield any significant differences in adult memory performance. However, two developmental time periods emerged as important for shaping memory following exposure to sexual abuse, but in opposite ways. Relative to non-exposed respondents, those exposed to sexual abuse during early childhood (ages 3-5), had better number recall and those first exposed during adolescence (ages 14-17) had worse number recall. However, other variables, including socioeconomic status, played a larger role (than maltreatment) on working and short-term memory. We conclude that a simple examination of "exposed" versus "unexposed" respondents may obscure potentially important within-group differences that are revealed by examining the effects of age at onset to maltreatment.

Social re-orientation and brain development: An expanded and updated view

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We expand our adolescent re-orientation model to include other developmental periods.

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We review neuroimaging literature on social information processing.

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We combine human and animal based approaches to social behavior.

Social development has been the focus of a great deal of neuroscience based research over the past decade. In this review, we focus on providing a framework for understanding how changes in facets of social development may correspond with changes in brain function. We argue that (1) distinct phases of social behavior emerge based on whether the organizing social force is the mother, peer play, peer integration, or romantic intimacy; (2) each phase is marked by a high degree of affect-driven motivation that elicits a distinct response in subcortical structures; (3) activity generated by these structures interacts with circuits in prefrontal cortex that guide executive functions, and occipital and temporal lobe circuits, which generate specific sensory and perceptual social representations. We propose that the direction, magnitude and duration of interaction among these affective, executive, and perceptual systems may relate to distinct sensitive periods across development that contribute to establishing long-term patterns of brain function and behavior.

Social scaffolding of human amygdala-mPFCcircuit development

Strong evidence indicates that reciprocal connections between the amygdala and the medial prefrontal cortex (mPFC) support fundamental aspects of emotional behavior in adulthood. However, this circuitry is slow to develop in humans, exhibiting immaturity in childhood. The argument is made that the development of this circuitry in humans is intimately associated with caregiving, such that parental availability during childhood provides important and enduring scaffolding of neuroaffective processes that ultimately form of the nature of the adult phenotype.

Social scaffolding of human amygdala-mPFCcircuit development

Strong evidence indicates that reciprocal connections between the amygdala and the medial prefrontal cortex (mPFC) support fundamental aspects of emotional behavior in adulthood. However, this circuitry is slow to develop in humans, exhibiting immaturity in childhood. The argument is made that the development of this circuitry in humans is intimately associated with caregiving, such that parental availability during childhood provides important and enduring scaffolding of neuroaffective processes that ultimately form of the nature of the adult phenotype.