Analyzing the Impact of Family Structure Changes on Children's Stress Levels Using a Stress Biomarker

Changes in family structure (e.g., parental separation or stepfamily formation) are associated with a deterioration in children's well-being. Most researchers have focused on the impact of such changes on children's educational and psychosocial outcomes, whereas the effects on children's biological processes have been studied less often. We analyze the effects of changes in family structure on children's stress levels using data from the German Health Interview and Examination Survey for Children and Adolescents study (2003-2006 and 2014-2017). Our outcome variable is the biomarker c-reactive protein (CRP), which correlates with psychological distress and is collected from blood samples. Calculating first-difference estimators, we analyze whether children have higher CRP levels after changing to (1) single-parent families (n = 117) or (2) stepfamilies (n = 80). Our findings suggest that changing to a single-parent family significantly increases children's stress, whereas changing to a stepfamily does not. These observations are important because increased stress in childhood can negatively affect well-being later in life.

What About the Children? Co-Occurrence of Child Maltreatment and Parental Separation

The aim of this study was to investigate (a) the extent to which child maltreatment co-occurs with parental separation and (b) associations between different types of child maltreatment and various types of separation-associated interparental conflict. Professionals working with children (N = 785) reported each case of suspected child maltreatment they observed during a 3-month period and indicated whether parental divorce or separation was about to take place or had taken place. This resulted in 530 reported cases that matched the definitions of child maltreatment for which information on parental relationship status was available. Most of the maltreated children (60%) also experienced (impending) parental separation. In 69% of these cases child maltreatment was associated with parental separation. Particularly, cases of emotional neglect, and emotional abuse co-occurred with parental separation. In addition, four clusters of separation-associated interparental conflict were distinguished- No observed conflict, Non-physical conflict, Verbal and physical conflict, and Multiple conflict-which were associated with child and family characteristics and specific types of child maltreatment. The results of this study suggest that child maltreatment often co-occurs with parental separation, especially when there is a considerable amount of interparental conflict.

Parental separation and death during childhood as predictors of adult psychopathology: An examination of racial differences

OBJECTIVE

Parental separation and parental death during childhood are common but understudied forms of adverse childhood events (ACEs), thus little is known about the impact on psychological functioning in adulthood. We examined whether parental death and parental separation during childhood was associated with risk of diagnostic criteria for depressive disorders, anxiety disorders, posttraumatic stress disorder (PTSD), or personality disorders during adulthood. Second, we compared parental separation and parental death and psychopathology across African Americans (N = 499) and Whites (N = 782).

METHOD

The sample consists of 1,211 participants (n = 669 females). Diagnostic interviews were administered by master's or doctorate-level degree holders in Clinical Psychology or Social Work. There was good to excellent interrater reliabilities (mean kappa of .84 ± .05; range: .79-.93) spanning anxiety, mood, anxiety, trauma, and personality disorders.

RESULTS

White participants reporting parental separation during childhood were more likely to report depressive disorders (OR = 2.151, p < .001), PTSD (OR = 2.218, p < .01) and personality disorders (OR = 1.764, p < .001) during adulthood. African American endorsement of parental separation during childhood did not predict depressive disorders (OR = 1.21, p = .357), anxiety disorders (OR = 1.107, p = .659), PTSD (OR = 1.351, p = .425) or personality disorders (OR = 1.432, p = .098) during adulthood. Overall, participants who reported parental death did not have significantly higher rates of depressive disorders (OR = 1.100, p = .668), anxiety disorders (OR = 1.357, p = .207), PTSD (OR = 1.351, p = .425), and personality disorders (OR = 1.432, p = .098).

CONCLUSIONS

Parental separation was a significant risk factor for adult psychopathology, but only for White participants. Parental death was not a risk factor for adult psychopathology no matter the person's race. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Parental Divorce and Adolescent Offending: A Comparison Between Children of Discordant Siblings

Various studies have found that parental divorce is associated with offspring offending during adolescence. Less is known, however, about the mechanisms underlying this association, and it may be possible that this association is spurious rather than causal. In this study, register data on 1,883,794 individuals, who were born in the Netherlands between 1991 and 2001, and their parents were used to examine to what extent parental divorce is associated with offspring adolescent offending. Moreover, a genetically-informed research design, in which children of discordant siblings (N = 59,102) were compared, was applied to examine whether unmeasured familial confounders (i.e., genetic and shared environment confounders) account for this association. Our findings suggest a positive relationship between parental divorce and adolescent offending, yet we find a weaker relationship when comparing offspring of discordant siblings. This suggests that previous studies may have overestimated the strength of the association, as they do not control for unmeasured familial confounders.

Parental separation and school dropout in adolescence

AIMS

To document the association between parental separation and school dropout in adolescence and to examine the factors that may potentially account for this association.

METHODS

Data stem from the large youth@hordaland study that was linked to the Norwegian National Educational Database to obtain objective measures of educational outcomes and disposable income (N = 8323). Logistic regression analysis was used to investigate the association between parental separation and school dropout. A Fairlie post-regression decomposition was used to examine the influence of parental education, household income, health complaints, family cohesion, and peer problems in explaining the association between parental separation and school dropout.

RESULTS

Parental separation was associated with a higher odds ratio (OR) of school dropout in crude and adjusted (adjusted odds ratio (AOR)) analyses (OR=2.16, 95% confidence interval (CI) =1.90-2.45; AOR = 1.72, 95% CI = 1.50-2.00). About 31% of the higher odds of school dropout among adolescents with separated parents was explained by the covariates. The decomposition analysis suggested that parental education (43%) and disposable income (20%) accounted for most of the explained differences in school dropout.

CONCLUSIONS

Adolescents with separated parents are at higher risk for not completing secondary education. Parental education and disposable income accounted for most of the explained differences in school dropout between the groups. Still, the majority of the difference in school dropout remained unaccounted for, indicating that the link between parental separation and school dropout is complex and likely influenced by multiple factors.

Mental Health in Schoolchildren in Joint Physical Custody: A Longitudinal Study

This study investigated mental health in schoolchildren in different living arrangements after parental separation. The study population included 31,519 children from the Danish National Birth Cohort, followed-up at age 11 in 2010–2014. Child mental health was measured with a maternal report of the Strength and Difficulties Questionnaire (SDQ). Associations between living arrangements and mental health were analyzed using logistic and linear regression models, taking into account early childhood indicators of the parents’ relations, income, education and psychiatric care. At age 11, children living in a nuclear family had the lowest rate of total SDQ score, 8.9%. Of the children who had experienced parental separation, children in joint physical custody had the lowest adjusted odds ratio (OR)1.25 (95%-CI 1.09–1.44), for a high SDQ score relative to children living in a nuclear family, with adjusted ORs of 1.63 (1.42–1.86) and OR 1.72 (1.52–1.95) for sole physical custody arrangements with and without a new partner. An analysis of change in SDQ scores between ages 7 and 11 in children showed a similar pattern. This study indicates that joint physical custody is associated with slightly more favorable mental health in schoolchildren after parental separation than sole physical custody arrangements.

Psychoanalytic infant observation in China-The mental health of children separated from parents

Through the lens of psychoanalytic infant observation, the authors introduce some characteristics of Chinese urban families, most of which have grandparents to participate in the caretaking of infants. In some cases, infants may be separated from parents. These phenomena are understood in terms of cultural, political, social, economic and psychological dimensions. The observational frame is compared to the clinical frame and the patient's handling of the frame throws light to his/her internal world. In some cases, this internal world may be populated by absent objects. Related mental health difficulties are illustrated by two clinical vignettes of adult patients who experienced long-term parental absence in childhood.

Psychosis in children of separated parents: A systematic review and meta-analysis

BACKGROUND

Parental separation is a very common childhood adversity. The association between other adverse childhood experiences and an increased risk of psychosis has been reported. However, the evidence on the risk of psychosis for children of separated parents is limited. In this systematic review, cohort, case-control, and cross-sectional studies, comparing the risk of psychotic disorders for people with and without separated parents, were searched, critically appraised, and summarized.

METHODS

Studies were searched in PubMed, EMBASE, PsycINFO, and the Web of Science, from database inception to September 2019. A meta-analysis, using random-effects models, was undertaken to obtain pooled estimates of the risk of psychosis among participants with separated parents.

RESULTS

Twelve studies, with 305,652 participants from 22 countries, were included in the review. A significantly increased risk of psychosis for those with separated parents was observed, with a pooled odds ratio: 1.53 (95% confidence interval [CI]: 1.29-1.76), p < 0.001. The association remained significant when cohort, case-control, and cross-sectional studies were analyzed separately. The five cohort studies included in this review showed and increased risk of psychosis with odds ratio: 1.47 (95% CI: 1.26-1.69), p < 0.001.

CONCLUSIONS

Parental separation is a common childhood adversity associated with an increased risk of psychosis. Although the risk for an individual child of separated parents is still low, given the high proportion of couple that separate, the increased rates of psychosis may be substantial in the population. Further studies on the risk of psychosis in those with separated parents, and the explanatory factors for this association, are required.

Parental Preference for Parental Separation and Their Satisfaction Regarding Their Children Dental Treatment in Pediatric Dental Clinics in Saudi Arabia

AIMS AND OBJECTIVES

Behavior management of child dental patients is essential for the provision of high-quality dental care and is influenced by parental preference. Therefore, this cross-sectional study aimed to assess parental satisfaction regarding dental treatment and different behavior management methods used with their children in a pediatric dental specialty setting at King Abdulaziz University Dental Hospital (KAUDH) in Jeddah, Saudi Arabia. In addition, it aimed to assess parental preference for parental separation and factors related to their preference.

MATERIALS AND METHODS

All parents of children attending the pediatric dental clinic at KAUDH in Jeddah, Saudi Arabia from September 2017 to June 2018 were included in this study. They were interviewed over the phone and were asked to complete a questionnaire on their acceptance of the behavior management techniques used with their children and their satisfaction with the treatment provided.

RESULTS

Of 549 parents, 283 agreed to participate (51.5% response rate). In 254 (89.7%) cases communication and communicative guidance were used, whereas 38 (13.4%) cases involved the use of N2O. Parental separation was preferred by 68 (24%) parents, and not preferred by 215 (76%). No significant relation was anticipated between the covariance and the dependent factor of parental preference (P > 0.05). The main reason for parents not preferring parental separation was "safety and protection," as reported by 106 parents. On the contrary, the main reason for parental preference for separation was to "improve child's behavior."

CONCLUSION

Parental satisfaction with the treatment outcome and behavior management methods was found to be acceptable. Most parents did not prefer parental separation, primarily because of concerns regarding safety and protection.

Adverse Childhood Experiences and Avatar Preferences in Online Games

This study investigates the relationship between adverse childhood experiences (ACEs), age, and sex with respect to their avatar preference in online games. The analyses comprise a subsample of n = 1817 adolescents and adults from 14 to 60 years within a representative German population-based study. Results indicate that 14 % of this sample uses avatars in online games, with significantly more males (22.6 %) than females (7.7 %) doing so. Persons with multiple ACEs (≥ 4) have a higher OR of 2.05 (95 % CI: 1.418-2.956) to use avatars in online games. Regarding avatar preference, females are more likely to play supporters than males, and males are more likely to choose damagers and mixed-type avatars than females. Participants with an experience of parental divorce during their childhood reported higher preference of playing supporter or mixed-type avatars in comparison with damager avatars. Moreover, participants with mental illness or suicide in the family show a higher preference of mixed-type avatars compared to damager, but not to supporter avatars. Knowledge about the use of avatars can be an interesting source of information for supporting psychotherapeutic treatment in a young age group.

Children with two homes: Psychological problems in relation to living arrangements in Nordic 2- to 9-year-olds

AIM

Joint physical custody, children spending equal time in each parents' respective home after a parental divorce, is particularly common in Nordic compared with other Western countries. Older children have been shown to fare well in this practice but for young children there are few existing studies. The aim of this paper is to study psychological problems in 2- to 9-year-old Nordic children in different family forms.

METHODS

Total symptom score according to the Strengths and Difficulties Questionnaire as well as scores showing externalizing problems were compared among 152 children in joint physical custody, 303 in single care and 3207 in nuclear families through multiple linear regression analyses.

RESULTS

Children in single care had more psychological symptoms than those in joint physical custody (B = 1.08; 95% CI 0.48 to 1.67) and those in nuclear families had the least reported symptoms (B = -0.53; 95% CI -0.89 to -0.17). Externalizing problems were also lower in nuclear families (B = -0.28, 95% CI -0.52 to -0.04) compared with joint physical custody after adjusting for covariates.

CONCLUSIONS

Young children with non-cohabiting parents suffered from more psychological problems than those in intact families. Children in joint physical custody had a lower total problem score than those in single care after adjusting for covariates. Longitudinal studies with information on family factors before the separation are needed to inform policy of young children's post-separation living arrangements.

Assessment of the effect of parental presence in dental operatory on the behavior of children aged 4-7 years

BACKGROUND

Child presents a unique challenge to accept a dental treatment, and such a challenge gets modified by the presence or the absence of a parent in the operatory. Many dentists have reportedly and controversially used parental separation anxiety as a tool to control behavior of an uncooperative child and also to deliver quality dental treatment in young children. But is the parental separation beneficial for dentist to gain child cooperation?

AIMS AND OBJECTIVES

The objective is to evaluate the influence of parental presence or absence in the operating room on child's behavior during dental procedure on children of 4 years and above.

MATERIALS AND METHODS

The study was carried out on 30 children of 4-7 years of age group, 16 (4-6 years) preschoolers, and 14 (6-7 years) early schoolers. Two consecutive restorative procedures were carried out. On a first visit, parents were present and on a second visit, separation of parents was done. Behavior rating was done by commonly used Frankel's Behavior Rating Scale.

RESULTS

Chi-square test was performed for the statistical analysis. There was no significant difference found in the child's behavior by the presence or absence of parents in the perception of dental treatment in the dental operatory. In contrast to that there was a significant increase in cooperative behavior of some children due to other factors influencing the behavior of the child with a Chi-square value = 35.296, P < 0.001.

CONCLUSION

Parents can be excluded from the dental operatory to eliminate many behavior-related problems during the course of treatment.

Impact of preterm birth on parental separation: a French population-based longitudinal study

OBJECTIVE

The objective of this study was to investigate both the effects of low gestational age and infant's neurodevelopmental outcome at 2 years of age on the risk of parental separation within 7 years of giving birth.

DESIGN

Prospective.

SETTING

24 maternity clinics in the Pays-de-la-Loire region.

PARTICIPANTS

This study included 5732 infants delivered at <35 weeks of gestation born between 2005 and 2013 who were enrolled in the population-based Loire Infant Follow-up Team cohort and who had a neurodevelopmental evaluation at 2 years. This neurodevelopmental evaluation was based on a physical examination, a psychomotor evaluation and a parent-completed questionnaire.

OUTCOME MEASURE

Risk of parental separation (parents living together or parents living separately).

RESULTS

Ten percent (572/5732) of the parents reported having undergone separation during the follow-up period. A mediation analysis showed that low gestational age had no direct effect on the risk of parental separation. Moreover, a non-optimal neurodevelopment at 2 years was associated with an increased risk of parental separation corresponding to a HR=1.49(1.23 to 1.80). Finally, the increased risk of parental separation was aggravated by low socioeconomic conditions.

CONCLUSIONS

The effect of low gestational age on the risk of parental separation was mediated by the infant's neurodevelopment.

What and How Much Do Children Lose in Academic Settings Owing to Parental Separation?

The literature has firmly established an association between parental separation and school failure. Nevertheless, parental separation does not affect academic aptitudes. Thus, mediators explain such relationship. A field study was designed to identify and quantify damage in the mediating variables between parental separation and school failure (i.e., external school adjustment, aversion to institution, aversion to learning, aversion to instruction, aversion to teachers, indiscipline). A total of 196 children, classified into three age cohorts: 109 in level 1 (from 8 to 11 years), 46 in level 2 (from 12 to 14 years), and 41 in level 3 (15 or more years), were assessed in school adjustment and in underlying dimensions of school (mal)adjustment. The results showed significant effects of parental separation in school adjustment and in the underlying dimensions to maladjustment in the three classification levels. The magnitude of damage increased with age, i.e., small in level 1, moderate in 2, and large in 3. Damage in all the sub-dimensions underlying school (mal)adjustment was quantified. The implications of the results for the design and implementation of prevention and intervention programs for children from separated parents are discussed.

Parental Separation and Cardiometabolic Risk Factors in Late Adolescence: A Cross-Cohort Comparison

The aim of this study was to explore the association between parental separation during childhood (up to 18 years of age) and cardiometabolic risk factors (body mass index, fat mass index, blood pressure, physical activity, smoking, and alcohol consumption) in late adolescence using a cross-cohort comparison and to explore whether associations differ according to the age at which the parental separation occurred and the presence or absence of parental conflict prior to separation. Data from the Avon Longitudinal Study of Parents and Children (ALSPAC, United Kingdom) (1991-2011) and the 1993 Pelotas Birth Cohort (Brazil) (1993-2011) were used. The associations of parental separation with children's cardiometabolic risk factors were largely null. Higher odds of daily smoking were observed in both cohorts for those adolescents whose parents separated (for ALSPAC, odds ratio = 1.46; for Pelotas Birth Cohort, odds ratio = 1.98). Some additional associations were observed in the Pelotas Birth Cohort but were generally in the opposite direction to our a priori hypothesis: Parental separation was associated with lower blood pressure and fat mass index, and with more physical activity. No consistent differences were observed when analyses were stratified by child's age at parental separation or parental conflict.

The association between parental separation during childhood and obesity in adulthood: a Danish twin study

Objective

The purpose of this study was to examine if parental separation during childhood is associated with obesity in adulthood.

Methods

A co‐twin case–control study of 146 adult same‐sexed twin pairs with discordant body mass index (BMI) (i.e. one of the twins should have a BMI of 20–25 kg/m², and the co‐twin's BMI ≥ 30 kg/m²) was selected from Danish Twin Registry (DTR). In total of 236 eligible twin individuals participated in the study. Childhood parental separation (defined as separation from one of the biological parents, regardless of the reason for separation) for at least one year prior to age 17 was self‐reported. The statistical analysis includes logistic and linear regression models using STATA 13.0.

Results

There were no differences in the odds of developing obesity in adulthood between the twin who stayed with a father and the co‐twin who was separated from him for at least 1 year prior to age 17 [OR = 1.22, 95%CI (0.46–3.34), p = 0.65]. Separation from a mother also showed no differences in the odds for developing obesity [OR = 0.90, 95%CI (0.32–2.46), p = 0.82].

Conclusions

Because of the limited number of discordant twin pairs for childhood parental separation, we cannot provide evidence to suggest that separation from parents in childhood was associated with developing obesity in adulthood. Further studies of pooling discordant twins from several countries should be considered.

Estimating the Epidemiology and Quantifying the Damages of Parental Separation in Children and Adolescents

Parental separation is linked to multiple negative outcomes for children in all spheres of life. A field study was designed to estimate the epidemiology and to quantify the outcomes on the wellbeing of children from separated parents. Thus, data on socio-economic status, psychological adjustment, behavioral disorders, social relations, self-concept, and academic achievement were gathered from 346 children and adolescents, 173 separated parents, and 173 parents from intact families in the paediatric catchment area of Galicia (Spain). The results showed that parental separation had a significant negative impact on the children’s and adolescents’ family income (increasing the probability of falling below the poverty line); psychological adjustment (i.e., higher scores in anxiety, depression, hostility, paranoid ideation, and interpersonal alienation); social relations (i.e., less self-control in social relations; higher social withdrawal); self-concept (lower levels of academic, emotional, physical, and family self-concept), and academic achievement (lower academic achievement with higher school dropout rates). Moreover, children from separated families had a higher probability of being exposed to gender violence. Epidemiologically, parental separation is associated to the probability of falling below the poverty line 33.9%; being exposed to gender violence 43.2%; and symptoms such as depression, anxiety, hostility, paranoid ideation interpersonal alienation, and social withdrawal, i.e., 20, 17, 27, 20, 19, and 35.5%, respectively. Inversely, self-control in social relations, and academic, emotional, physical, and family self-concept fell to 16, 32, 27, 22, and 37%, respectively. The interrelationship among these variables and the implications of these results for interventions are discussed.

A population-based study of the risk of schizophrenia and bipolar disorder associated with parent-child separation during development

BACKGROUND

There is growing interest in the role of childhood adversities, including parental death and separation, in the etiology of psychotic disorders. However, few studies have used prospectively collected data to specifically investigate parental separation across development, or assessed the importance of duration of separation, and family characteristics.

METHOD

We measured three types of separation not due to death: maternal, paternal, and from both parents, across the ages of 1-15 years among a cohort of 985 058 individuals born in Denmark 1971-1991 and followed to 2011. Associations with narrowly and broadly defined schizophrenia and bipolar disorder in the psychiatric register were assessed in terms of separation occurrence, age of separation, and number of years separated. Interactions with parental history of mental disorder were assessed.

RESULTS

Each type of separation was associated with all three outcomes, adjusting for age, sex, birth period, calendar year, family history of mental disorder, urbanicity at birth and parental age. Number of years of paternal separation was positively associated with both schizophrenia and bipolar disorder. Associations between separation from both parents and schizophrenia were stronger when separation occurred at later ages, while those with bipolar disorder remained stable across development. The first occurrence of paternal separation appeared to increase risk more when it occurred earlier in childhood. Associations differed according to parental history of mental disorder, although in no situation was separation protective.

CONCLUSIONS

Effects of parental separation may differ by type, developmental timing and family characteristics. These findings highlight the importance of considering such factors in studies of childhood adversity.

Early parental loss and depression history: associations with recent life stress in major depressive disorder

Although exposure to early adversity and prior experiences with depression have both been associated with lower levels of precipitating life stress in depression, it is unclear whether these stress sensitization effects are similar for all types of stress or whether they are specific to stressors that may be particularly depressogenic, such as those involving interpersonal loss. To investigate this issue, we administered structured, interview-based measures of early adversity, depression history, and recent life stress to one hundred adults who were diagnosed with major depressive disorder. As predicted, individuals who experienced early parental loss or prolonged separation (i.e., lasting one year or longer) and persons with more lifetime episodes of depression became depressed following lower levels of life stress occurring in the etiologically-central time period of three months prior to onset of depression. Importantly, however, additional analyses revealed that these effects were unique to stressors involving interpersonal loss. These data highlight potential stressor-specific effects in stress sensitization and demonstrate for the first time that individuals exposed to early parental loss or separation, and persons with greater histories of MDD, may be selectively sensitized to stressors involving interpersonal loss.

Childhood parental loss and adult psychopathology: effects of loss characteristics and contextual factors

The purpose of this study was to determine whether childhood parental death and childhood parental separation are linked to lifetime depressive and anxiety disorders after controlling for related risk factors. Participants were 105 individuals from the community, including a group with separation/desertion from a parent, a group with childhood parental death, and a matched control group whose parents remained married and living together. Participants completed interviews and questionnaires assessing symptoms of anxiety and depression, family psychiatric history, childhood maltreatment, and childhood parental relationships. Participants with separation/desertion and those with parental death were significantly more likely than the control subjects to report the subsequent onset of symptoms of a depressive or anxiety disorder. These effects were not fully explained by parental relationships or childhood maltreatment. However, in the group with parental separation only, family history of depressive and anxiety disorders accounted for the apparent effect of parental separation. These findings indicate that parental death may be a specific risk factor for depressive and anxiety disorders. For parental separation/desertion, our results highlight the overriding influence of risk factors that commonly co-occur with this form of parental loss.

Juvenile emotional experience alters synaptic composition in the rodent cortex, hippocampus, and lateral amygdala

A quantitative anatomical study in the rodent anterior cingulate and somatosensory cortex, hippocampus, and lateral amygdala revealed region-, cell-, and dendrite-specific changes of spine densities in 3-week-old Octodon degus after repeated parental separation. In parentally separated animals significantly higher spine densities were found on the apical and basal dendrites of the cingulate cortex (up to 143% on apical and 138% on basal dendrite). Branching order analysis revealed that this effect is seen on all segments of the apical dendrite, whereas on the basal dendrites significantly higher spine densities were seen only on the outer branches (third to fifth dendritic segments). Increased spine densities were also observed on the hippocampal CA1 pyramidal neurons (up to 109% on the distal apical segments and up to 106% on the basal segment) compared with the control group. In contrast, significantly reduced spine densities were observed on the granule cell dendrites in the dentate gyrus (down to 92%) and on the apical dendrites in the medial nucleus of the amygdala (down to 95%). No significant changes of spine densities were seen in the somatosensory cortex (except for an increase in the proximal apical segments) and in the lateral nucleus of the dorsal amygdala (except for an increase in the proximal basal dendritic segments). These results demonstrate that repeated stressful emotional experience alters the balance of presumably excitatory synaptic inputs of pyramidal neurons in the limbic system. Such experience-induced modulations of limbic circuits may determine psychosocial and cognitive capacities during later life.

Separation-induced receptor changes in the hippocampus and amygdala of Octodon degus: influence of maternal vocalizations

Relatively little is known about the basic mechanisms that play a role in the vulnerability of the developing brain toward adverse environmental influences. Our study in the South American rodent Octodon degus revealed that repeated brief separation from the parents and exposure to an unfamiliar environment induces in the hippocampal formation of male and female pups an upregulation of D1 and 5-HT1A receptor density in the stratum radiatum and stratum lacunosum moleculare of the CA1 region. In the CA3 region, only the 5-HT1A receptors were upregulated; no changes were observed for D1 receptors in this region. GABA(A) receptor density in the hippocampus and amygdala was downregulated (nonsignificant trend) after parental separation. The acoustic presence of the mother during parental separation suppressed the D1 and 5-HT1A receptor upregulation in some regions of the hippocampus; no such suppressing influence was observed for the GABA(A) receptors. In the basomedial amygdala, the maternal calls enhanced the separation-induced 5-HT1A receptor upregulation in the male pups, whereas in the female pups the separation-induced receptor densities were not only suppressed by the maternal call but further downregulated, compared with the control group. These results demonstrate that early adverse emotional experience alters aminergic function within the hippocampus and amygdala and that the mother's voice, a powerful emotional signal, can modulate these effects in the developing limbic system.