The effects of maltreatment and neuroendocrine regulation on memory performance

Association between Hpa Axis Functioning and Mental Health in Maltreated Children and Adolescents: A Systematic Literature Review

BACKGROUND

Previous studies have demonstrated that children who experience maltreatment show a more elevated risk of psychopathological disorders than children from the general population. The HPA (hypothalamic-pituitary-adrenal) axis is not mature at birth and undergoes strong social regulation during the first years of life. Consequently, early exposure to stress could modify the usual adaptative response to stress. In stressful situations, perturbations in both cortisol response and cortisol circadian rhythm have been observed. Nevertheless, studies that have evaluated the links between child abuse, dysregulation of the HPA axis, and mental disorders have shown diverse results. Because of the variety of methods employed in the different studies, no formal comparisons have been made. In this systematic review, we have brought together these results.

METHODS

We conducted a systematic review of studies analyzing the correlation between child abuse, mental disorders, and HPA axis activity in patients aged between 6 and 16 years. PubMed, Scopus, Cochrane, and Google Scholar were searched using relevant keywords and inclusion/exclusion criteria (from 2000 to 2020).

RESULTS

Fifteen studies from the 351 identified were included. Most patients were children in the child welfare system. Children who had experienced child abuse presented with more severe mental disorders (particularly in the dimensional measure) than children who had not been abused. HPA axis activity was assessed by measuring basal cortisol for some studies and cortisol reactivity for other studies. For children experiencing child abuse, there was a possible association between abuse and a decrease in the reactivity of the HPA axis. In addition, early life stress could be associated with lower matinal cortisol. However, the association between mental disorders and cortisol secretion in maltreated children did not seem obvious.

CONCLUSIONS

This systematic review demonstrates that mental disorders are more frequent and severe in cases where child abuse has occurred. Moreover, children who experienced child abuse seem to present changes in the reactivity of the HPA axis. Nevertheless, the potential correlation between these changes in the reactivity of the HPA axis and mental disorders in this population needs to be evaluated in further studies.

Stress, memory, and implications for major depression

The stress response comprises a phylogenetically conserved set of cognitive, physiological, and behavioral responses that evolved as a survival strategy. In this context, the memory of stressful events would be adaptive as it could avoid re-exposure to an adverse event, otherwise the event would be facilitated in positively stressful or non-distressful conditions. However, the interaction between stress and memory comprises complex responses, some of them which are not yet completely understood, and which depend on several factors such as the memory system that is recruited, the nature and duration of the stressful event, as well as the timing in which this interaction takes place. In this narrative review, we briefly discuss the mechanisms of the stress response, the main memory systems, and its neural correlates. Then, we show how stress, through the action of its biochemical mediators, influences memory systems and mnemonic processes. Finally, we make use of major depressive disorder to explore the possible implications of non-adaptive interactions between stress and memory to psychiatric disorders, as well as possible roles for memory studies in the field of psychiatry.

Current Posttraumatic Stress Symptoms Mediate the Relationship Between Adverse Childhood Experiences and Executive Functions

Adverse childhood experiences (ACEs) and posttraumatic stress disorder (PTSD) are both associated with lower performances on executive function tasks. However, few researchers have evaluated ACEs, posttraumatic stress (PTS) symptoms, and executive function difficulties in conjunction. Using an online micropayment service, the current study assessed whether PTS symptoms mediated the relationship between ACEs and executive functions. In total, 83 participants (54.2% female, age: M = 28.86, SD = 7.71) were administered the ACE questionnaire, PTSD Checklist for DSM-5 (PCL-5), and the Executive Function Index (EFI). A higher number of reported ACEs was related to greater PTS symptom severity (β = .40, p < .001) and worse self-rated executive functions (β = -.32, p = .002). Controlling for the number of reported ACEs, current PTS symptom severity was related to worse executive functions (β = -.45, p < .001). A bootstrapped 95% confidence interval (CI) indicated a significant indirect effect, β = -.18 (95% CI: -.30, -.08), by which current PTS symptoms mediated the relationship between the number of reported ACEs and executive functions. These results suggest that psychological interventions targeting PTS symptoms, in the context of a history of childhood trauma, may concurrently improve executive functions in adult populations.

Functional Alterations and Cerebral Variations in Humans Exposed to Early Life Stress

Early life stress can be caused by acute or chronic exposure to childhood events, such as emotional, physical, sexual abuse, and neglect. Early stress is associated with subsequent alterations in physical and mental health, which can extend into adolescence, adulthood, and even old age. The effects of early stress exposure include alterations in cognitive, neuropsychological, and behavioral functions, and can even lead to the development of psychiatric disorders and changes in brain anatomy. The present manuscript provides a review of the main findings on these effects reported in the scientific literature in recent decades. Early life stress is associated with the presence of psychiatric disorders, mainly mood disorders such as depression and risk of suicide, as well as with the presence of post-traumatic stress disorder. At the neuropsychological level, the involvement of different mental processes such as executive functions, abstract reasoning, certain memory modalities, and poor school-skill performance has been reported. In addition, we identified reports of alterations of different subdomains of each of these processes. Regarding neuroanatomical effects, the involvement of cortical regions, subcortical nuclei, and the subcortical white matter has been documented. Among the telencephalic regions most affected and studied are the prefrontal cortex, the hippocampus, the amygdala, and the anterior cingulate cortex. Understanding the impact of early life stress on postnatal brain development is very important for the orientation of therapeutic intervention programs and could help in the formulation and implementation of preventive measures as well as in the reorientation of research targets.

Intergenerational maltreatment and child emotion dysregulation

BACKGROUND

Childhood maltreatment has been related to adverse outcomes on social, cognitive, and biological development with sequelae present throughout the lifespan. As such, caregivers maltreated in childhood may face a different set of challenges and interpersonal stressors in rearing their children. Parental history of maltreatment has the potential to increase the risk of parental depression and exposure to maltreatment in the next generation, both of which can have a negative effect on children's development.

OBJECTIVE

The purpose of this study is to investigate maternal depression and child experiences of maltreatment as mediators of the relationship between mothers' own maltreatment experiences and child emotion dysregulation in children aged 10-12.

PARTICIPANTS AND SETTING

378 low-income mothers and their children were recruited to participate in a research summer camp from 2004-2007.

METHOD

Mothers self-reported on their experiences of maltreatment in childhood and current depressive symptoms. Current generation child maltreatment information was coded from Child Protective Services records. Child emotion dysregulation (rated by camp counselors) was the outcome measure in this study. Structural equation modeling was employed to test associations between maternal maltreatment and child emotion dysregulation.

RESULTS

Maternal history of maltreatment related to both child maltreatment (β = .24, SE = .052, p < .001) and greater maternal depressive symptoms (β = .28, SE = .049, p < .001). Only child maltreatment mediated the effect of mothers' maltreatment on child emotion dysregulation (95 %CI: .005-.023).

CONCLUSIONS

In this low-income sample, the rate of intergenerational maltreatment is high and represents a pathway of influence that increases risk for maladaptive socioemotional child development.

Identifying maltreatment subgroups with patterns of maltreatment subtype and chronicity: A latent class analysis approach

Maltreatment experiences are complex, and it is difficult to characterize the heterogeneity in types of maltreatment. Subtypes, such as emotional maltreatment, sexual abuse, physical abuse, and neglect commonly co-occur and may persist across development. Therefore, treating individual maltreatment subtypes as independently occurring is not representative of the nature of maltreatment as it occurs in children's lives. Latent class analysis (LCA) is employed herein to identify subgroups of maltreated children based on commonalities in maltreatment subtype and chronicity. In a sample of 674 low-income urban children, 51.6% of whom experienced officially documented maltreatment, our analyses identified four classes of children, with three distinct classes based on maltreatment subtypes and chronicity, and one group of children who did not experience maltreatment. The largest class of maltreated children identified was the chronic, multi-subtype maltreatment class (57% of maltreated children); a second class was characterized by only neglect in a single developmental period (31% of maltreated children), and the smallest class was characterized by a single subtype of maltreatment (emotional maltreatment, physical, or sexual abuse) occurring in a single developmental period (12% of maltreated children). Characterization of these groups confirms the overlapping nature of maltreatment subtypes. There were notable differences between latent classes on child behavioral and socio-emotional outcomes measured by child self-report and camp counselors report during a one-week summer camp. The largest differences were between the non-maltreated class and the chronic maltreatment class. Children who experienced chronic, multi-subtype maltreatment showed higher levels of externalizing behavior, emotion dysregulation, depression, and anxiety.

Suggestibility in neglected children: The influence of intelligence, language, and social skills

We administered the GSS-2, a standardised measure of suggestibility, to 5- to 12-year-old children to ascertain whether neglected children's responses to leading questions distinguish them from those of their non-neglected counterparts. Neglected children (n = 75) were more likely than an age-matched sample of non-neglected children (n = 75) to yield to leading questions, despite no difference in their ability to recall the test stimuli. Subsequent collection of individual difference data from the neglected sample revealed that this effect could not be attributed to intelligence, language ability, problem behaviours, age at onset of neglect, or time spent in out-of-home care. With respect to social skill, however, suggestibility was positively correlated with communicative skill, and marginally positively correlated with assertion and engagement. While on the surface our social skills findings seem counter-intuitive, it is possible that maltreated children with relative strengths in these areas have learned to comply with adults in their environment as a way to protect themselves or even foster belonging. Our data, while preliminary, raise interesting questions about whether targeted interventions could help these children to more actively participate in decisions about their lives.

FOOD NEGLECT AND INFANT DEVELOPMENT

The impact of food insecurity on child development in the general U.S. population is well-established, yet little is known about the harm of food neglect relative to other types of maltreatment. Due to the harmful physiological impact of inadequate nutrients and the social impact of food-related stress, it was hypothesized that food neglect would be more likely to impair infant cognitive and language development than physical abuse, sexual abuse, and other forms of neglect. Families of infants (N = 1,951) investigated by Child Protective Services were studied using the second cohort of the National Survey of Child and Adolescent Well-Being (NSCAW II; NSCAW Research Group, 2002). Results from multivariable logistic regression models that controlled for likely confounding variables showed that the odds of impairment in cognition and language were significantly greater when food neglect was the most serious form of maltreatment. Considering that both food insecurity and child neglect are associated with poverty and parental mental health problems, it will be important for child welfare and mental health professionals to work collaboratively to better the health of these vulnerable children.

Diurnal cortisol slopes and mental and physical health outcomes: A systematic review and meta-analysis

Changes in levels of the stress-sensitive hormone cortisol from morning to evening are referred to as diurnal cortisol slopes. Flatter diurnal cortisol slopes have been proposed as a mediator between chronic psychosocial stress and poor mental and physical health outcomes in past theory and research. Surprisingly, neither a systematic nor a meta-analytic review of associations between diurnal cortisol slopes and health has been conducted to date, despite extensive literature on the topic. The current systematic review and meta-analysis examined associations between diurnal cortisol slopes and physical and mental health outcomes. Analyses were based on 179 associations from 80 studies for the time period up to January 31, 2015. Results indicated a significant association between flatter diurnal cortisol slopes and poorer health across all studies (average effect size, r=0.147). Further, flatter diurnal cortisol slopes were associated with poorer health in 10 out of 12 subtypes of emotional and physical health outcomes examined. Among these subtypes, the effect size was largest for immune/inflammation outcomes (r=0.288). Potential moderators of the associations between diurnal cortisol slopes and health outcomes were examined, including type of slope measure and study quality indices. The possible roles of flatter slopes as either a marker or a mechanism for disease etiology are discussed. We argue that flatter diurnal cortisol slopes may both reflect and contribute to stress-related dysregulation of central and peripheral circadian mechanisms, with corresponding downstream effects on multiple aspects of biology, behavior, and health.

The childhood maltreatment influences on breast cancer patients: A second wave hit model hypothesis for distinct biological and behavioral response

Stress and cancer are two complex situations involving different biological and psychological mechanisms. Their relationship have long been studied, and there is evidence of the impact stress has on both, development and disease progression. Furthermore, early stress has been studied as an important factor associated to this relationship, since its impacts on the immune, endocrine and cognitive development throughout life is already known. Therefore, understanding early stress as a first wave of stress in life is necessary in order to explore a possible second wave hit model. From this perspective, we believe that breast cancer can be understood as a second wave of stress during development and that, in addition to the first wave, can cause important impacts on the response to cancer treatment, such as increased chances of disease progression and distinct behavioral responses. In this article we propose a second wave hit hypothesis applied to breast cancer and its implications on the immune, endocrine and cognitive systems, through mechanisms that involve the HPA axis and subsequent activations of stress responses.

Plasticity of risky decision making among maltreated adolescents: Evidence from a randomized controlled trial

Childhood maltreatment has lasting negative effects throughout the life span. Early intervention research has demonstrated that these effects can be remediated through skill-based, family-centered interventions. However, less is known about plasticity during adolescence, and whether interventions are effective many years after children experience maltreatment. This study investigated this question by examining adolescent girls' ability to make advantageous decisions in the face of risk using a validated decision-making task; performance on this task has been associated with key neural regions involved in affective processing and executive functioning. Maltreated foster girls (n = 92), randomly assigned at age 11 to either an intervention designed to prevent risk-taking behaviors or services as usual (SAU), and nonmaltreated age and socioeconomic status matched girls living with their biological parent(s) (n = 80) completed a decision-making task (at age 15-17) that assessed risk taking and sensitivity to expected value, an index of advantageous decision making. Girls in the SAU condition demonstrated the greatest decision-making difficulties, primarily for risks to avoid losses. In the SAU group, frequency of neglect was related to greater difficulties in this area. Girls in the intervention condition with less neglect performed similarly to nonmaltreated peers. This research suggests that early maltreatment may impact decision-making abilities into adolescence and that enriched environments during early adolescence provide a window of plasticity that may ameliorate these negative effects.

Mental Health, Behavioral and Developmental Issues for Youth in Foster Care

Youth in foster care represent a unique population with complex mental and behavioral health, social-emotional, and developmental needs. For this population with special healthcare needs, the risk for adverse long-term outcomes great if needs go unaddressed or inadequately addressed while in placement. Although outcomes are malleable and effective interventions exist, there are barriers to optimal healthcare delivery. The general pediatrician as advocate is paramount to improve long-term outcomes.

Childhood abuse and neglect may induce deficits in cognitive precursors of psychosis in high-risk children

BACKGROUND

Millions of children are born to parents affected by major psychoses. Cognitive dysfunctions seen in patients are already detectable in these children. In parallel, childhood maltreatment increases the risk of adult psychoses through unknown mechanisms. We investigated whether high-risk offspring exposed to abuse/neglect displayed more cognitive precursors of adult psychoses in childhood and adolescence than nonexposed offspring.

METHODS

We used a stepwise selection strategy from a 25-year follow-up of 48 densely affected kindreds including 1500 adults (405 patients with schizophrenia or bipolar disorder) to select high-risk offspring aged 6-22 years for inclusion in our study. All offspring were assessed for childhood trauma from direct interviews with the offspring, parents and relatives and from the review of lifetime medical records of parents and children and administered a neuropsychological battery including IQ and 4 of the most impaired neuropsychological domains in psychoses.

RESULTS

Our study included 66 high-risk offspring. Those who were exposed to abuse/neglect had significantly lower IQ (effect size [ES] = 0.61) than nonexposed offspring and displayed poorer cognitive performance in visual episodic memory (ES = 0.67) and in executive functions of initiation (ES = 1.01). Moreover, exposed offspring presented more combinations of cognitive deficits that were associated with lower Global Assessment of Functioning scores.

LIMITATIONS

Exposure to abuse/neglect was not assessed in the control group, thus the study could not test whether the effect of childhood maltreatment occurred only in a high-risk setting and not in the general population.

CONCLUSION

In high-risk youths, maltreatment in childhood/adolescence may negatively impact cognitive domains known to be impaired in adults with psychoses, suggesting an early mediating effect in the association between abuse/neglect and adult psychoses. This finding provides a target for future developmental and preventive research.

Child abuse, disruptive behavior disorders, depression, and salivary cortisol levels among institutionalized and community-residing boys in Mongolia

INTRODUCTION

Hypothalamic-pituitary-adrenal (HPA) axis activity is related to childhood disruptive behavior disorders and to exposure to abuse and neglect. This study explores the relationship of diurnal salivary cortisol levels with oppositional defiant disorder (ODD) and caregiver attitudes toward physical punishment among boys in Mongolia.

METHODS

Salivary cortisol was collected in the home or institution 4 times daily for 4 days from 46 boys, aged 4-10 years, in Ulaanbaatar, Mongolia. Caregivers rated child disruptive behavior symptoms, attitudes toward physical punishment, and community violence exposures. Mixed effects models were used to estimate the association of psychopathology and caregiver attitudes with salivary cortisol levels.

RESULTS

Boys meeting criteria for ODD displayed consistently lower diurnal salivary cortisol levels compared to boys without ODD diagnoses. Controlling for ODD diagnosis, boys with depression showed higher cortisol levels throughout the day. No other diagnosis was associated with cortisol levels. Psychiatric diagnosis accounted for 17% of between individual variations in cortisol levels unexplained by the covariates. In a separate model, caregivers' beliefs regarding physical punishment accounted for 11% of between individual differences: boys with caregivers who stated physical punishment was necessary for discipline displayed hypocortisolism. Institutionalization did not associate with cortisol levels.

DISCUSSION

Salivary cortisol data from a non-Western naturalistic setting support an association of reduced basal HPA activity with disruptive behavior disorders and caregiver attitudes toward discipline. These findings suggest HPA functioning may be a reflection of or mediate disruptive behavior disorders in children across ethnic and cultural settings.

Four-month-old infants' long-term memory for a stressful social event

Infants clearly show an early capacity for memory for inanimate emotionally neutral events. However, their memory for social stress events has received far less attention. The aim of the study was to investigate infants' memory for a stressful social event (i.e., maternal unresponsiveness during the Still-Face paradigm) after a 15-day recall interval using changes in behavioral responses and salivary post-stress cortisol reactivity as measures of memory. Thirty-seven infants were exposed to social stress two times (experimental condition); the first time when they were 4 months of age and second exposure after a 2 week interval. Infants in the control condition (N = 37) were exposed to social stress just one time, at the age corresponding to the second exposure for infants in the experimental condition (4 months plus 2 weeks). Given individual differences in infants' reactivity to social stress events, we categorized infants as increasers or decreasers based on their cortisol reactivity after their initial exposure to the stress of the maternal still-face. Infants in the experimental condition, both increasers and decreasers, showed a significant change in cortisol response after the second exposure to the maternal still-face, though change was different for each reactivity group. In contrast, age-matched infants with no prior exposure to the maternal still-face showed similar post-stress cortisol reactivity to the reactivity of the experimental infants at their first exposure. There were no behavioral differences between increasers and decreasers during the Still-Face paradigm and exposures to the social stress. Thus differences between the experimental and control groups' post-stress cortisol reactivity was associated with the experimental group having previous experience with the social stress. These findings indicate long-term memory for social stress in infants as young as 4 months of age.

The formation of secure new attachments by children who were maltreated: an observational study of adolescents in foster care

Children who were maltreated and enter foster care are at risk for maladjustment and relationship disturbances with foster carers. A popular hypothesis is that prior attachment relationships with abusive birth parents are internalized and carried forward to impair the child's subsequent attachment relationships. However, the empirical base for this model is limited, especially in adolescence. We examined the attachment patterns of 62 adolescents with their birth parents and their foster parents; we compared them to a comparison sample of 50 adolescents in normal-risk families. Attachment was assessed using the Child Attachment Interview; adolescent-parent interaction quality was assessed from direct observation; disruptive behavior symptoms were assessed from multiple informants. Whereas nearly all of the adolescents in foster families exhibited insecure attachments to their birth mothers (90%) and birth fathers (100%), nearly one-half were classified as having a secure attachment with their foster mother (46%) and father (49%); rates of secure attachment toward foster parents did not differ significantly from the rate in comparison families. Within the foster care sample, attachment security to the foster mother was predicted from current observed relationship quality and the duration of current placement. In addition, attachment quality in foster adolescents was associated with fewer disruptive behavior symptoms, and this association was equally strong in foster and comparison families. Our findings demonstrate that there is substantial potential for maltreated children to change and develop subsequent secure attachments in adolescence.

The impact of neglect on initial adaptation to school

This study examined the impact of child neglect during the first 4 years of life on adaptation to school during kindergarten and first grade in the context of neighborhood poverty (NP). Processes related to the development of school competencies were examined, including the mediational role of cognitive functioning and ego-resiliency (ER) in shaping children's school outcomes. A total of 170 low-income urban children were followed prospectively for 2 years (ages 4-6). Results indicated that neglected children had significantly lower scores on kindergarten classroom behavior and first-grade academic performance than nonneglected children. Children's cognitive performance at age 4, controlling for maternal intelligence quotient, mediated the relation between severity of neglect and children's behavior in kindergarten as well as their academic performance in first grade. Moreover, severity of neglect was related to children's ER at age 4. However, additional ecological adversity in the form of NP moderated the link between ER and classroom behavior, such that at lower levels of poverty, ER mediated the relation between severity of neglect and school adaptation. Conversely, when NP was extreme, the effects of ER were attenuated and ER ceased to predict behavioral performance in kindergarten. The implications of these findings for prevention and intervention are discussed.

Intervention Effects on Morning and Stimulated Cortisol Responses Among Toddlers in Foster Care

Toddlers in child welfare often have a dysregulated stress response. We tested whether toddlers with caregivers randomized to a 10-week attachment-based intervention, Promoting First Relationships (PFR; Kelly, Sandoval, Zuckerman, & Buehlman, 2008) would show post-intervention change in stimulated salivary cortisol patterns during a research home visit involving a separation-reunion procedure, compared to a condition including child development and resource advice, but no attachment strategies. At baseline and post intervention, toddlers with a caregiver change within 7 weeks of enrollment (n=48, age 10-25 months) provided 4 saliva samples during a 1.5-hour research visit, and samples the next morning. The categorical dependent variable was the pattern of cortisol activity during the course of the post-intervention research visit: Flat, Decreasing, Increasing. Multinomial logistic regression was used to test for post-intervention group differences in cortisol patterns, controlling for time of day, child's age, morning cortisol level, and baseline cortisol pattern. At baseline and post-intervention 92% of children demonstrated atypically low morning cortisol (< .21 ig/dL); Post-intervention, Flat, Decreasing and Increasing patterns were exhibited by 70%, 15%, and 15% of the sample, respectively. Significantly more children in the PFR condition showed an Increasing pattern. This may signal an intervention effect on separation-based stress response physiology.

Exposure to interpersonal violence and risk for PTSD, depression, delinquency, and binge drinking among adolescents: data from the NSA-R

Interpersonal violence (IPV) is associated with a range of subsequent negative outcomes; however, research has yet to test whether IPV operates as a specific risk factor for separate psychopathology outcomes, such as posttraumatic stress disorder (PTSD) symptoms, depressive symptoms, delinquent acts, or binge drinking. To address this, cumulative exposure to IPV and non-IPV-related traumatic events, PTSD symptoms, depressive symptoms, delinquent acts, and binge drinking were measured 3 times over approximately 3 years among a nationally representative sample of adolescents aged 12-17 (N = 3,614 at Wave 1). Results demonstrated that cumulative IPV exposure predicted subsequent PTSD, depression, delinquency, and binge drinking (βs = .07, .12, .10, and .09, respectively; all ps < .01) when all cross-relationships (e.g., the effect of delinquency on future binge drinking) were in the model. Exposure to non-IPV traumatic events generally did not confer vulnerability to subsequent psychopathology outcomes. Overall, findings from this study advance the literature in this area by exploring consequences for adolescents following cumulative IPV exposure.

A transdisciplinary perspective of chronic stress in relation to psychopathology throughout life span development

The allostatic load (AL) model represents an interdisciplinary approach to comprehensively conceptualize and quantify chronic stress in relation to pathologies throughout the life cycle. This article first reviews the AL model, followed by interactions among early adversity, genetics, environmental toxins, as well as distinctions among sex, gender, and sex hormones as integral antecedents of AL. We next explore perspectives on severe mental illness, dementia, and caregiving as unique human models of AL that merit future investigations in the field of developmental psychopathology. A complimenting transdisciplinary perspective is applied throughout, whereby we argue that the AL model goes beyond traditional stress–disease theories toward the advancement of person-centered research and practice that promote not only physical health but also mental health.