Neurobiological consequences of early stress and childhood maltreatment: are results from human and animal studies comparable?

Role of sensory, social, and hormonal signals from the mother on the development of offspring

For mammals, sensory, social, and hormonal experience early in life is essential for the continuity of the infant's development. These experiences come from the mother through maternal care, and have enduring effects on the physiology and behavior of the adult organism. Disturbing the mother-offspring interaction by maternal deprivation (neglect) or exposure to adverse events as chronic stress, maltreatment, or sexual abuse has negative effects on the mental, psychological, physiological, and behavioral health. Indeed, these kinds of negative experiences can be the source of some neuropsychiatric diseases as depression, anxiety, impulsive aggression, and antisocial behavior. The purpose of this chapter is to review the most relevant evidence that supports the participation of cues from the mother and/or littermates during the postnatal preweaning period for the development of nervous system of the offspring. These findings come from the most frequently utilized experimental paradigms used in animal models, such as natural variations in maternal behavior, handling, partial maternal deprivation, and total maternal deprivation and artificial rearing. Through the use of these experimental procedures, it is possible to positively (handling paradigm), or negatively (maternal deprivation paradigms), affect the offspring's development. Finally, this chapter reviews the importance of the hormones that pups ingest through the maternal milk during early lactation on the development of several physiological systems, including the immune, endocrine systems, as well as on the adult behavior of the offspring.

Adverse childhood experiences influence white matter microstructure in patients with bipolar disorder

BACKGROUND

Bipolar disorder (BD) is associated with adverse childhood experiences (ACE), which worsen the lifetime course of illness, and with signs of widespread disruption of white matter (WM) integrity in adult life. ACE are associated with changes in WM microstructure in healthy humans.

METHOD

We tested the effects of ACE on diffusion-tensor imaging (DTI) measures of WM integrity in 80 in-patients affected by a major depressive episode in the course of BD. We used whole-brain tract-based spatial statistics in the WM skeleton with threshold-free cluster enhancement of DTI measures of WM microstructure: axial, radial and mean diffusivity, and fractional anisotropy.

RESULTS

ACE hastened the onset of illness. We observed an inverse correlation between the severity of ACE and DTI measures of axial diffusivity in several WM fibre tracts contributing to the functional integrity of the brain and including the corona radiata, thalamic radiations, corpus callosum, cingulum bundle, superior longitudinal fasciculus, inferior fronto-occipital fasciculus and uncinate fasciculus.

CONCLUSIONS

Axial diffusivity reflects the integrity of axons and myelin sheaths, and correlates with functional connectivity and with higher-order abilities such as reasoning and experience of emotions. In patients with BD axial diffusivity is increased by lithium treatment. ACE might contribute to BD pathophysiology by hampering structural connectivity in critical cortico-limbic networks.

Early life stress in epilepsy: a seizure precipitant and risk factor for epileptogenesis

Stress can influence epilepsy in multiple ways. A relation between stress and seizures is often experienced by patients with epilepsy. Numerous questionnaire and diary studies have shown that stress is the most often reported seizure-precipitating factor in epilepsy. Acute stress can provoke epileptic seizures, and chronic stress increases seizure frequency. In addition to its effects on seizure susceptibility in patients with epilepsy, stress might also increase the risk of epilepsy development, especially when the stressors are severe, prolonged, or experienced early in life. Although the latter has not been fully resolved in humans, various preclinical epilepsy models have shown increased seizure susceptibility in naïve rodents after prenatal and early postnatal stress exposure. In the current review, we first provide an overview of the effects of stress on the brain. Thereafter, we discuss human as well as preclinical studies evaluating the relation between stress, epileptic seizures, and epileptogenesis, focusing on the epileptogenic effects of early life stress. Increased knowledge on the interaction between early life stress, seizures, and epileptogenesis could improve patient care and provide a basis for new treatment strategies for epilepsy.

Hippocampal volume is inversely related to PTSD duration

Numerous imaging studies have reported smaller hippocampal volumes in patients with PTSD. To investigate whether decreased hippocampal volume is associated with PTSD chronicity, independent of age, we used hierarchical linear regression to examine the relationship between PTSD duration (estimated from the amount of time that had elapsed since the traumatic event; mean=17 years; range=6-36 years) and hippocampal volume, adjusting for age and other factors. Freesurfer version 4.5 was used to quantify the volumes of the hippocampus and the caudate nucleus, which served as a "control" region, from the 1.5T Magnetic Resonance Images (MRI) of 55 combat veterans (mean age 45±9 years) with chronic and current PTSD. PTSD duration was significantly associated with right hippocampal volume (β=-0.34, t=-2.40, P=0.02) after accounting for intracranial volume, age, gender (entered in the first step) and comorbidities (e.g., early life trauma, current major depression, history of substance abuse/dependence, psychotropic medication use, entered in the second step). This finding provides support for the potential neurotoxic effects of PTSD on hippocampal volume.

Effects of early life adverse experiences on the brain: implications from maternal separation models in rodents

During postnatal development, adverse early life experiences affect the formation of neuronal networks and exert long-lasting effects on neural function. Many studies have shown that daily repeated maternal separation (MS), an animal model of early life stress, can regulate the hypothalamic-pituitary-adrenal axis (HPA axis) and affect subsequent brain function and behavior during adulthood. However, the molecular basis of the long-lasting effects of early life stress on brain function has not been fully elucidated. In this mini review, we present various cases of MS in rodents and illustrate the alterations in HPA axis activity by focusing on corticosterone (CORT). We then show a characterization of the brain regions affected by various patterns of MS, including repeated MS and single time MS at various stages before weaning, by investigating c-Fos expression. These CORT and c-Fos studies suggest that repeated early life stress may affect neuronal function in region- and temporal-specific manners, indicating a critical period for habituation to early life stress. Next, we introduce how early life stress can impact behavior, namely by inducing depression, anxiety or eating disorders, and alterations in gene expression in adult mice subjected to MS.

Associations between the SS variant of 5-HTTLPR and PTSD among adults with histories of childhood emotional abuse: results from two African American independent samples

BACKGROUND

Prior studies have found that the 5-HTTLPR polymorphism in the promoter region of the serotonin transporter gene (SLC6A4) interacts with stressful life events to increase general risk for PTSD, but this association has not extended to African American samples. Further, little is known about the effects of this interaction on specific PTSD symptom clusters, despite indications that clusters may have different biological substrates. The current study examined the interaction between exposure to childhood emotional abuse and 5-HTTLPR genotype on risk for PTSD symptom severity and severity of specific PTSD symptom clusters in two African American samples.

METHODS

Participants were 136 African American household residents from Detroit, MI and 546 African American patients recruited from waiting rooms in primary care clinics in Atlanta, GA. Participants reported emotional abuse exposure and PTSD symptom severity, and provided DNA for triallelic 5-HTTLPR genotyping. Analysis of covariance (ANCOVA) was used to examine main effects and interactions.

RESULTS

In both African American samples, 5-HTTLPR genotype modified the effect of emotional abuse on PTSD symptom severity. Participants with the low-expression SS genotype who were exposed to emotional abuse had significantly lower reexperiencing and arousal symptom severity scores.

LIMITATIONS

The DNHS genetic sample size was small, and abuse data were assessed retrospectively.

CONCLUSIONS

The SS variant of 5-HTTLPR appears to buffer against developing the reexperiencing and arousal symptoms of PTSD in two independent African American samples exposed to childhood emotional abuse. Findings also highlight the importance of considering emotional abuse experiences in patients with suspected PTSD.

Reducing substance use during adolescence: a translational framework for prevention

RATIONALE

Most substance use is initiated during adolescence when substantial development of relevant brain circuitry is still rapidly maturing. Developmental differences in reward processing, behavioral flexibility, and self-regulation lead to changes in resilience or vulnerability to drugs of abuse depending on exposure to risk factors. Intervention and prevention approaches to reducing addiction in teens may be able to capitalize on malleable brain systems in a predictable manner.

OBJECTIVE

This review will highlight what is known about how factors that increase vulnerability to addiction, including developmental stage, exposure to early life adversity (ranging from abuse, neglect, and bullying), drug exposure, and genetic predisposition, impact the development of relevant systems.

RESULTS AND CONCLUSIONS

Appropriate, early intervention may restore the normal course of an abnormal trajectory and reduce the likelihood of developing a substance use disorder (SUD) later in life. A considerable amount is known about the functional neuroanatomy and/or pharmacology of risky behaviors based on clinical and preclinical studies, but relatively little has been directly translated to reduce their impact on addiction in high-risk children or teenagers. An opportunity exists to effectively intervene before adolescence when substance use is likely to emerge.

Interventions to improve cortisol regulation in children: a systematic review

Childhood adversity is associated with physiologic dysregulation across multiple biological systems; however, relatively little is known about whether these changes are reversible with intervention. The objective of this review was to examine evidence for the effectiveness of interventions to promote healthy cortisol regulation in children. We selected articles from English-language publications in PubMed and EBSCO databases through 2012. Two independent reviewers assessed articles against eligibility criteria. Eligible studies were randomized controlled or quasi-experimental studies designed to improve relationships, environments, or psychosocial functioning in children and examined cortisol as an outcome. We identified 19 articles. There was substantial heterogeneity across studies with regard to age, selection criteria, intervention design, cortisol assessment, and follow-up duration. Eighteen of the 19 articles reported at least 1 difference in baseline cortisol, diurnal cortisol, or cortisol responsivity between intervention and control participants. Importantly, however, there was remarkable inconsistency with regard to how the interventions influenced cortisol. Therefore, studies that included a low-risk comparison group (n = 8) provided critical insight, and each found some evidence that postintervention cortisol levels in the intervention group approximated the low-risk comparison group and differed from children receiving usual care. In conclusion, existing studies show that cortisol activity can be altered by psychosocial interventions. These findings are promising, not only because they indicate physiologic plasticity that can be leveraged by interventions but also because they suggest it may be possible to repair regulatory systems after childhood adversity, which could inform strategies for reducing health disparities and promoting lasting improvements in health.

Psychophysiology of dissociated consciousness

Recent study of consciousness provides an evidence that there is a limit of consciousness, which presents a barrier between conscious and unconscious processes. This barrier likely is specifically manifested as a disturbance of neural mechanisms of consciousness that through distributed brain processing, attentional mechanisms and memory processes enable to constitute integrative conscious experience. According to recent findings a level of conscious integration may change during certain conditions related to experimental cognitive manipulations, hypnosis, or stressful experiences that can lead to dissociation of consciousness. In psychopathological research the term dissociation was proposed by Pierre Janet for explanation of processes related to splitting of consciousness due to traumatic events or during hypnosis. According to several recent findings dissociation of consciousness likely is related to deficits in global distribution of information and may lead to heightened levels of "neural complexity" that reflects brain integration or differentiation based on numbers of independent neural processes in the brain that may be specifically related to various mental disorders.

Balance deficits and ADHD symptoms in medication-naïve school-aged boys

BACKGROUND AND OBJECTIVES

Functional disturbances developed early in life include balance deficits which are linked to dysfunctions of higher levels of cognitive and motor integration. According to our knowledge, there are only a few studies suggesting that balance deficits are related to behavioral disturbances in attention-deficit/hyperactivity disorder (ADHD).

METHODS

We tested the extent to which balance deficits were related to ADHD symptoms in 35 medication-naïve boys of school age (8-11 years) and compared the results with a control group of 30 boys of the same age.

RESULTS

ADHD symptoms in medication-naïve boys had specific relationships to disturbances of postural and gait balance.

CONCLUSION

To our knowledge, this study provides the first evidence in the medical literature for a direct relationship between ADHD symptoms and balance deficits, that cannot be attributed to medication and the presence of any neurological disease.

Nonlinear measures and dynamics in psychophysiology of consciousness

According to recent findings nonlinear dynamic processes related to neural chaos and complexity likely play a crucial role in neural synchronization of distributed neural activities that enable information integration and conscious experience. Disturbances in these interactions produce patterns of temporal and spatial disorganization with decreased or increased functional connectivity and complexity that underlie specific changes of perceptual and cognitive states. These perceptual and cognitive changes may be characterized by neural chaos with significantly increased brain sensitivity that may underlie sensitization and kindling, and cognitive hypersensitivity in some mental disorders. Together these findings suggest that processes related to more irregular neural states with higher complexity that may lead to neural chaos, negatively affect information integration and processing in the brain, and may influence disintegrated conscious experience.

Family poverty affects the rate of human infant brain growth

Living in poverty places children at very high risk for problems across a variety of domains, including schooling, behavioral regulation, and health. Aspects of cognitive functioning, such as information processing, may underlie these kinds of problems. How might poverty affect the brain functions underlying these cognitive processes? Here, we address this question by observing and analyzing repeated measures of brain development of young children between five months and four years of age from economically diverse backgrounds (n = 77). In doing so, we have the opportunity to observe changes in brain growth as children begin to experience the effects of poverty. These children underwent MRI scanning, with subjects completing between 1 and 7 scans longitudinally. Two hundred and three MRI scans were divided into different tissue types using a novel image processing algorithm specifically designed to analyze brain data from young infants. Total gray, white, and cerebral (summation of total gray and white matter) volumes were examined along with volumes of the frontal, parietal, temporal, and occipital lobes. Infants from low-income families had lower volumes of gray matter, tissue critical for processing of information and execution of actions. These differences were found for both the frontal and parietal lobes. No differences were detected in white matter, temporal lobe volumes, or occipital lobe volumes. In addition, differences in brain growth were found to vary with socioeconomic status (SES), with children from lower-income households having slower trajectories of growth during infancy and early childhood. Volumetric differences were associated with the emergence of disruptive behavioral problems.

Cortical thickness, surface area, and gyrification abnormalities in children exposed to maltreatment: neural markers of vulnerability?

BACKGROUND

Childhood maltreatment has been shown to significantly elevate the risk of psychiatric disorder. Previous neuroimaging studies of children exposed to maltreatment have reported atypical neural structure in several regions, including the prefrontal cortex and temporal lobes. These studies have exclusively investigated volumetric differences rather than focusing on genetically and developmentally distinct indices of brain structure.

METHODS

Here we used surface-based methods to examine cortical thickness, surface area, and local gyrification in a community sample of children with documented experiences of abuse (n = 22) and a group of carefully matched nonmaltreated peers (n = 21).

RESULTS

Reduced cortical thickness in the maltreated compared with the nonmaltreated group was observed in an extended cluster that incorporated the anterior cingulate, superior frontal gyrus, and orbitofrontal cortex. In addition, reduced cortical surface area was observed within the parcellated regions of the left middle temporal area and lingual gyrus. Local gyrification deficits within the maltreated group were located within two clusters, the lingual gyrus and the insula extending into pars opercularis.

CONCLUSIONS

This is the first time structural abnormalities in the anterior cingulate and lingual gyrus have been detected in children exposed to maltreatment. Surface-based methods seem to capture subtle, previously undetected, morphological abnormalities associated with maltreatment. We suggest that these approaches detect developmental precursors of brain volume differences seen in adults with histories of abuse. Because the reported regions are implicated in several clinical disorders, they might constitute biological markers of vulnerability, linking exposure to early adversity and psychiatric risk.

Childhood exposure to violence and lifelong health: clinical intervention science and stress-biology research join forces

Many young people who are mistreated by an adult, victimized by bullies, criminally assaulted, or who witness domestic violence react to this violence exposure by developing behavioral, emotional, or learning problems. What is less well known is that adverse experiences like violence exposure can lead to hidden physical alterations inside a child's body, alterations that may have adverse effects on life-long health. We discuss why this is important for the field of developmental psychopathology and for society, and we recommend that stress-biology research and intervention science join forces to tackle the problem. We examine the evidence base in relation to stress-sensitive measures for the body (inflammatory reactions, telomere erosion, epigenetic methylation, and gene expression) and brain (mental disorders, neuroimaging, and neuropsychological testing). We also review promising interventions for families, couples, and children that have been designed to reduce the effects of childhood violence exposure. We invite intervention scientists and stress-biology researchers to collaborate in adding stress-biology measures to randomized clinical trials of interventions intended to reduce effects of violence exposure and other traumas on young people.

A neuropsychological profile of childhood maltreatment within an adolescent inpatient sample

Recent research has begun to identify the neurocognitive and psychological effects of childhood maltreatment, although information is limited on the neuropsychological presentation of maltreatment in psychiatrically hospitalized adolescents. This study examined the executive-functioning and language abilities as well as psychopathological presentation of childhood maltreatment victims in an adolescent psychiatric inpatient setting. The sample consisted of adolescent inpatients (ages 13-19 years old) who completed a neuropsychological/psychological assessment during hospitalization (n = 122). The sample was grouped based on childhood maltreatment history, with one group categorized by maltreatment history (n = 49) and the other group characterized by no maltreatment history (n = 73). Analyses revealed statistically significant differences (p < .01) between maltreatment groups on executive functioning, as well as on measures of self-reported depression and anxiety symptoms. No group differences remained after controlling for posttraumatic stress disorder. Further, distinct neuropsychological profiles were identified for specific types of maltreatment experienced. These findings suggest that while childhood maltreatment is associated with a range of neuropsychological impairments, the specific type of maltreatment experienced may have a significant influence on the type and severity of impairments. These findings contribute to the growing body of research on the significant consequences of childhood maltreatment.

Translational reciprocity: bridging the gap between preclinical studies and clinical treatment of stress effects on the adolescent brain

The genetic, biological, and environmental backgrounds of an organism fundamentally influence the balance between risk and resilience to stress. Sex, age, and environment transact with responses to trauma in ways that can mitigate or exacerbate the likelihood that post-traumatic stress disorder will develop. Translational approaches to modeling affective disorders in animals will ultimately provide novel treatments and a better understanding of the neurobiological underpinnings behind these debilitating disorders. The extant literature on trauma/stress has focused predominately on limbic and cortical structures that innervate the hypothalamic-pituitary-adrenal axis and influence glucocorticoid-mediated negative feedback. It is through these neuroendocrine pathways that a self-perpetuating fear memory can propagate the long-term effects of early life trauma. Recent work incorporating translational approaches has provided novel pathways that can be influenced by early life stress, such as the glucocorticoid receptor chaperones, including FKBP51. Animal models of stress have differing effects on behavior and endocrine pathways; however, complete models replicating clinical characteristics of risk and resilience have not been rigorously studied. This review discusses a four-factor model that considers the importance of studying both risk and resilience in understanding the developmental response to trauma/stress. Consideration of the multifactorial nature of clinical populations in the design of preclinical models and the application of preclinical findings to clinical treatment approaches comprise the core of translational reciprocity, which is discussed in the context of the four-factor model.

Structural modulation of brain development by oxygen: evidence on adolescents migrating from high altitude to sea level environment

The present study aimed to investigate structural modulation of brain by high level of oxygen during its peak period of development. Voxel-based morphometry analysis of gray matter (GM) and white matter (WM) volumes and Tract-Based Spatial Statistics analysis of WM fractional anisotropy (FA) and mean diffusion (MD) based on MRI images were carried out on 21 Tibetan adolencents (15-18 years), who were born and raised in Qinghai-Tibetan Plateau (2900-4700 m) and have lived at sea level (SL) in the last 4 years. The control group consisted of matched Tibetan adolescents born and raised at high altitude all the time. SL immigrants had increased GM volume in the left insula, left inferior parietal gyrus, and right superior parietal gyrus and decreased GM in the left precentral cortex and multiple sites in cerebellar cortex (left lobule 8, bilateral lobule 6 and crus 1/2). Decreased WM volume was found in the right superior frontal gyrus in SL immigrants. SL immigrants had higher FA and lower MD at multiple sites of WM tracts. Moreover, we detected changes in ventilation and circulation. GM volume in cerebellum lobule 8 positively correlated with diastolic pressure, while GM volume in insula positively correlated vital capacity and hypoxic ventilatory response. Our finding indicate that the structural modulations of GM by high level of oxygen during its peak period of development are related to respiratory and circulatory regulations, while the modulation in WM mainly exhibits an enhancement in myelin maturation.

Clinical validity of a brief measure of early childhood social-emotional/behavioral problems

OBJECTIVE

To address a pressing need for measures of clinically significant social-emotional/behavioral problems in young children by examining several validity indicators for a brief parent-report questionnaire.

METHODS

An ethnically and economically diverse sample of 213 referred and nonreferred 2- and 3-year-olds was studied. The validity of the Brief Infant-Toddler Social-Emotional Assessment (BITSEA) Problem Index and Internalizing and Externalizing scales was evaluated relative to a "gold standard" diagnostic interview, as well as the Child Behavior Checklist (CBCL).

RESULTS

The validity of the BITSEA Problem Index relative to Diagnosis (sensitivity = 72.7%-80.8%, specificity = 70.0%-83.3%) and clinical-range CBCL scores (sensitivity = 80.0%-96.2%, specificity = 75.0%-89.9%) was supported in the full sample and within minority/nonminority groups. Additional results supported the validity of the BITSEA Internalizing and Externalizing scales.

CONCLUSIONS

Documented validity suggests that the BITSEA may be a valuable tool to aid screening, identification, and assessment efforts targeting early-emergent social-emotional/behavioral problems. Practical implications and generalizability are discussed.

Epileptic-like symptoms and stress conditions in adolescents

According to recent clinical data, epileptiform changes in temporolimbic structures may be related to psychopathological symptoms known to be related to stress. These data are also consistent with findings that temporal lobe epileptiform activity may provoke various somatic, sensory, behavioral, and memory disturbances similar to temporolimbic seizures and may lead to complex partial seizure-like symptoms which may also occur in nonepileptic conditions. Together, these findings suggest a hypothesis concerning the extent to which psychopathological changes usually related to stress may be associated with complex partial seizure-like symptoms or whether these symptoms might more likely be explained by various somatic factors. To test the hypothesis in a sample particularly vulnerable to stress, these relations between stress-related psychopathology and complex partial seizure-like symptoms were examined in a sample of 340 adolescents. Complex partial seizure-like symptoms were significantly associated with stress-related psychopathology: even mild stress may cause symptoms similar to cognitive and affective disturbances observed in patients with complex partial seizures.

Early life adversity alters the developmental profiles of addiction-related prefrontal cortex circuitry

Early adverse experience is a well-known risk factor for addictive behaviors later in life. Drug addiction typically manifests during adolescence in parallel with the later-developing prefrontal cortex (PFC). While it has been shown that dopaminergic modulation within the PFC is involved in addiction-like behaviors, little is known about how early adversity modulates its development. Here, we report that maternal separation stress (4 h per day between postnatal days 2–20) alters the development of the prelimbic PFC. Immunofluorescence and confocal microscopy revealed differences between maternally-separated and control rats in dopamine D1 and D2 receptor expression during adolescence, and specifically the expression of these receptors on projection neurons. In control animals, D1 and D2 receptors were transiently increased on all glutamatergic projection neurons, as well as specifically on PFC→nucleus accumbens projection neurons (identified with retrograde tracer). Maternal separation exacerbated the adolescent peak in D1 expression and blunted the adolescent peak in D2 expression on projection neurons overall. However, neurons retrogradely traced from the accumbens expressed lower levels of D1 during adolescence after maternal separation, compared to controls. Our findings reveal microcircuitry-specific changes caused by early life adversity that could help explain heightened vulnerability to drug addiction during adolescence.

Evidence for a neuroinflammatory mechanism in delayed effects of early life adversity in rats: relationship to cortical NMDA receptor expression

Postnatal maternal separation in rats causes a reduction of GABAergic parvalbumin-containing interneurons in the prefrontal cortex that first occurs in adolescence. This parvalbumin loss can be prevented by pre-adolescent treatment with a non-steroidal anti-inflammatory drug that also protects against excitotoxicity. Therefore, the neuropsychiatric disorders associated with early life adversity and interneuron dysfunction may involve neuroinflammatory processes and/or aberrant glutamatergic activity. Here, we aimed to determine whether delayed parvalbumin loss after maternal separation was due to inflammatory activity, and whether central administration of the anti-inflammatory cytokine interleukin (IL)-10 could protect against such loss. We also investigated the effects of maternal separation and IL-10 treatment on cortical NMDA receptor expression. Male rat pups were isolated for 4h/day between postnatal days 2-20. IL-10 was administered intracerebroventricularly through an indwelling cannula between P30 and 38. Adolescent prefrontal cortices were analyzed using Western blotting and immunohistochemistry for parvalbumin and NMDA NR2A subunit expression. We demonstrate that central IL-10 administration during pre-adolescence protects maternally separated animals from parvalbumin loss in adolescence. Linear regression analyses revealed that increased circulating levels of the pro-inflammatory cytokines IL-1β and IL-6 predicted lowered parvalbumin levels in maternally separated adolescents. Maternal separation also increases cortical expression of the NR2A NMDA receptor subunit in adolescence, which is prevented by IL-10 treatment. These data suggest that inflammatory damage to parvalbumin interneurons may occur via aberrant glutamatergic activity in the prefrontal cortex. Our findings provide a novel interactive mechanism between inflammation and neural dysfunction that helps explain deleterious effects of early life adversity on prefrontal cortex interneurons.

Effects of early life stress on brain activity: implications from maternal separation model in rodents

Adverse experiences in early life can affect the formation of neuronal circuits during postnatal development and exert long-lasting influences on neural function. Many studies have shown that daily repeated maternal separation (RMS), an animal model of early life stress, can modulate the hypothalamic-pituitary-adrenal axis (HPA-axis) and can affect subsequent brain function and emotional behavior during adulthood. However, the molecular basis of the long-lasting effects of early life stress on brain function has not been completely elucidated. In this mini-review, we introduce various cases of maternal separation in rodents and illustrate the alterations in HPA-axis activity by focusing on corticosterone (CORT), an end-product of the HPA-axis in rodents. We then present the characterization of the brain regions affected by various patterns of MS, including RMS and single time maternal separation (SMS) at various stages before weaning, by investigating c-Fos expression, a biological marker of neuronal activity. These CORT and c-Fos studies suggest that repeated early life stress may affect neuronal function in region- and temporal-specific manners, indicating a critical period for habituation to early life stress. Furthermore, we introduce changes in behavioral aspects and gene expression in adult mice exposed to RMS.

Persisting primitive reflexes in medication-naïve girls with attention-deficit and hyperactivity disorder

BACKGROUND AND OBJECTIVES

Recent and historical findings suggest that later-developed functions during brain ontogenesis related to higher levels of cognitive and motor integration tend to replace the older, more primitive, ones, and the persistence of the older functions may be linked to specific neuropsychiatric disorders. Currently, there is growing evidence to suggest that persisting primitive reflexes may be related to developmental and neurodegenerative disorders. Preliminary data also suggest that persisting primitive reflexes may be specifically linked to attention-deficit and hyperactivity disorder (ADHD).

METHODS

In the study reported here, we tested to what extent the persisting primitive asymmetric tonic neck reflex and symmetric tonic neck reflex are related to ADHD symptoms measured by Conners' Parent Questionnaire in 35 medication-naïve girls of school age (8-11 years) with ADHD. The results were compared with those of a control group of 30 girls of the same age.

RESULTS

This study showed that persisting primitive reflexes are closely linked to ADHD symptoms.

CONCLUSION

The data suggest that ADHD symptoms may be linked to more primitive neural mechanisms interfering with higher brain functions due to insufficiently developed cognitive and motor integration.

Belastungen in der Kindheit und dissoziative Symptomatik bei Patienten mit psychischen Störungen

Theoretischer Hintergrund: Dissoziative Symptome treten bei verschiedenen psychischen Störungen auf und werden bei einigen Störungen mit traumatischen Erfahrungen assoziiert. Fragestellung: Wird der Zusammenhang zwischen dissoziativer Symptomatik und belastenden Erfahrungen moduliert durch die Art der Erfahrung und das Alter zum Zeitpunkt der Belastung? Methode: Bei 82 Patienten (Borderline-Persönlichkeitsstörung, BPS; Major Depression Disorder, MDD) und 54 gesunden Kontrollpersonen wurden per Interview belastende Erfahrungen während Kindheit und Jugend (3 – 16 Jahre) ermittelt. Zusammenhänge zwischen Belastung und dissoziativer Symptomatik wurden regressionsanalytisch unter Berücksichtigung von Diagnose und komorbider Posttraumatischer Belastungsstörung (PTBS) untersucht. Ergebnisse: Dissoziative Symptomatik korreliert bei BPD und MDD (mit komorbider PTBS) positiv mit emotionalem (neben sexuellem) Missbrauch und mit Belastungen in der Pubertät. Schlussfolgerung: Therapeutische Berücksichtigung emotionaler und pubertärer Belastung könnte die (Behandlung erschwerende) dissoziative Symptomatik reduzieren.

Exposure to childhood neglect and physical abuse and developmental trajectories of heavy episodic drinking from early adolescence into young adulthood

BACKGROUND

Although the literature suggests that childhood maltreatment (CM) relates to adolescent heavy episodic drinking (HED), few studies have examined the long-term effects of CM on adolescent HED. This study is the first to examine associations between exposure to CM and trajectories of HED from adolescence to young adulthood for the US population.

METHODS

Four waves of data from the National Longitudinal Study of Adolescent Health were used. A total of 8503 adolescents followed from adolescence (7th-12th grades) into young adulthood (ages 24-32) were assessed on CM and past-year HED frequency. Using growth curve modeling, trajectories of adolescent HED were examined, with subtype, frequency, and severity of CM as the primary independent variables. All of our analyses controlled for common risk factors for adolescent HED, including demographics, parental and peer alcohol use, parental education and employment, family income, parent-child relationship, and adolescent depression.

RESULTS

After controlling for potential risk factors, neglect and physical abuse, both individually and in conjunction, were associated with faster increases in HED during adolescence and persistently elevated HED over much of adolescence and young adulthood. The frequency of neglect and physical abuse, individually and in conjunction, was also associated with the trajectory of HED, such that additional instances of these types of maltreatment were associated with faster increases in HED during adolescence and higher rates of peak use during young adulthood.

CONCLUSION

Child neglect and physical abuse appear to have long-lasting adverse effects on HED beyond adolescence and throughout much of young adulthood.

Repeated restraint stress increases basolateral amygdala neuronal activity in an age-dependent manner

Chronic stress is a precipitating factor for affective disorders such as depression and anxiety. This is associated with the effects of chronic stress on the amygdala. Adolescents may be more vulnerable to the effects of chronic stress, which may be related to its impact on amygdala function. However, the stress-induced changes in amygdala neuronal activity, and the age-dependent impact of chronic stress on amygdala neuronal activity have not been studied in depth. In this study, we investigated how repeated restraint impacts basolateral amygdala (BLA) projection neuron activity in both adolescent and adult rats. Using in vivo extracellular recordings from anesthetized rats, we found that repeated restraint increased the number of spontaneously firing neurons in the BLA of adolescent rats, but did not significantly increase the firing rate. In contrast, repeated restraint increased the firing rate of BLA neurons in adult rats, but did not change the number of spontaneously firing neurons. This is the first direct evidence of how stress differently impacts amygdala physiology in adolescent and adult rats. These findings may shed light on the mechanism by which chronic stress may age-dependently precipitate psychiatric disorders.

Relationship between structural abnormalities in the cerebellum and dementia, posttraumatic stress disorder and bipolar disorder

New evidence suggests that the cerebellum has structural and functional abnormalities in psychiatric disorders.

Objective

In this research, the goal was to measure the volume of the cerebellum and its subregions in individuals with psychiatric disorders and to relate these findings to their symptoms.

Methods

Patients with different degrees of cognitive impairment (Epidemiology of the Elderly - UNIFESP) and patients with post-traumatic stress disorder (PTSD) from population studies were analyzed. Also, patients with bipolar disorder from an outpatient clinic (Center for the Study of Mood and Anxiety Disorders, Universidade Federal da Bahia) were recruited for this study. All subjects underwent a 1.5T structural magnetic resonance scan. Volumetric measures and symptom measurements, by psychometric scales, were performed and compared between patients and controls.

Results

The cerebellum volume was reduced in patients with cognitive impairment without dementia and with dementia, in patients with PTSD, and in patients with bipolar disorder compared to controls. In dementia and PTSD, the left cerebellar hemisphere and vermis volume were reduced. In bipolar disorder, volumes of both hemispheres and the vermis were reduced. In the first two studies, these cerebellar volumetric reductions correlated with symptoms of the disease.

Conclusion

The exact nature of cerebellar involvement in mental processes is still not fully understood. However, abnormalities in cerebellar structure and its functions have been reported in some of these diseases. Future studies with larger samples are needed to clarify these findings and investigate whether they are important for treatment and prognosis.

White matter disruptions in adolescents exposed to childhood maltreatment and vulnerability to psychopathology

Childhood maltreatment has been known to produce long-lasting impairments in behavioral, cognitive and social functioning, but their underlying mechanisms are not well-understood. A better understanding of their underlying mechanisms will aid in developing effective preventive interventions. Nineteen adolescent volunteers with no personal history of a psychiatric illness, but who were exposed to maltreatment during childhood, and 13 adolescent volunteers with no personal or family history of a psychiatric disorder (controls) underwent diffusion tensor imaging (DTI) studies. The participants were then followed longitudinally at 6-month intervals for up to 5 years to determine the onset of mood and substance use disorders. The associations among fractional anisotropy (FA) values obtained from the DTI scans at baseline and psychopathology at follow-up were examined. At baseline, adolescents exposed to childhood maltreatment had significantly lower FA values in the left and right superior longitudinal fasciculi, right cingulum bundle projecting to the hippocampus, left inferior fronto-occipital fasciculus, and splenium of the corpus callosum compared with controls. Adolescents who developed major depressive disorder at follow-up had significantly lower FA values in the superior longitudinal fasciculi and the right cingulum-hippocampal projection compared with their counterparts who did not develop the illness. Adolescents who developed substance use disorder during follow-up had significantly lower FA values in the right cingulum-hippocampal projection than their counterparts without the disorder. These preliminary results suggest that white matter disruptions observed in adolescents exposed to childhood maltreatment may be associated with increased vulnerability to psychopathology, specifically depressive and substance use disorders.

Early Maternal Withdrawal and Nonverbal Childhood IQ as Precursors for Substance Use Disorder in Young Adulthood: Results of a 20-Year Prospective Study

The relation between early mother-infant interaction and later socio-emotional development has been well established. The present study addresses the more recent interest in the impact of maternal caregiving on cognitive development and their role in decision-making in young adulthood. Using data from a prospective longitudinal study on attachment, prediction from early mother-infant interactions at age 18 months and from verbal and nonverbal cognitive skill at age 5 were examined as predictors of a substance use disorder (abuse/dependence) in young adulthood (age 20) on the Structured Clinical Interview for DSM-IV (SCID). Results reveal that the mother's withdrawal from interaction with the infant at age 18 months, coded using the AMBIANCE coding system (Atypical Maternal Behavior Instrument for Assessment and Classification), was associated with the child's lower nonverbal cognitive scores but not verbal cognitive scores at age 5. In addition, maternal withdrawal at 18 months predicted a clinical diagnosis of substance use disorder (alcohol/cannabis) at age 20. Finally, nonverbal reasoning at age 5 mediated the relationship between early maternal withdrawal and substance use disorder (alcohol/cannabis) in young adulthood. Findings indicate the need for further work examining how early maternal withdrawal affects nonverbal cognitive development by school entry, and how these nonverbal deficits further contribute to maladaptive coping strategies such as substance use by young adulthood.

Gray matter differences between healthy and depressed adolescents: a voxel-based morphometry study

BACKGROUND

Major depressive disorder (MDD) frequently begins during adolescence and is associated with significant morbidity and mortality. However, little is known about the neurobiology of adolescent depression. A better understanding of the neurobiology will be helpful in developing more effective preventive and treatment interventions for this highly disabling illness.

METHODS

Using a voxel-based morphometric method, the study compared gray matter and white matter volumes in 22 adolescents with MDD and 22 age- and gender-matched normal controls.

RESULTS

Compared with controls, depressed adolescents had smaller gray matter volume in the frontal lobe and caudate nucleus bilaterally and right superior and middle temporal gyri. However, the groups did not differ significantly on white matter volume.

CONCLUSIONS

These findings in depressed adolescents are consistent with the previous findings of gray matter abnormalities in frontolimbic areas and the striatum in depressed adults and suggest the presence of these structural changes at the onset of depressive illness.

Childhood maltreatment is associated with reduced volume in the hippocampal subfields CA3, dentate gyrus, and subiculum

Childhood maltreatment or abuse is a major risk factor for mood, anxiety, substance abuse, psychotic, and personality disorders, and it is associated with reduced adult hippocampal volume, particularly on the left side. Translational studies show that the key consequences of stress exposure on the hippocampus are suppression of neurogenesis in the dentate gyrus (DG) and dendritic remodeling in the cornu ammonis (CA), particularly the CA3 subfield. The hypothesis that maltreatment is associated with volume reductions in 3-T MRI subfields containing the DG and CA3 was assessed and made practical by newly released automatic segmentation routines for FreeSurfer. The sample consisted of 193 unmedicated right-handed subjects (38% male, 21.9 ± 2.1 y of age) selected from the community. Maltreatment was quantified using the Adverse Childhood Experience study and Childhood Trauma Questionnaire scores. The strongest associations between maltreatment and volume were observed in the left CA2-CA3 and CA4-DG subfields, and were not mediated by histories of major depression or posttraumatic stress disorder. Comparing subjects with high vs. low scores on the Childhood Trauma Questionnaire and Adverse Childhood Experience study showed an average volume reduction of 6.3% and 6.1% in the left CA2-CA3 and CA4-DG, respectively. Volume reductions in the CA1 and fimbria were 44% and 60% smaller than in the CA2-CA3. Interestingly, maltreatment was associated with 4.2% and 4.3% reductions in the left presubiculum and subiculum, respectively. These findings support the hypothesis that exposure to early stress in humans, as in other animals, affects hippocampal subfield development.

Childhood adversity and epigenetic modulation of the leukocyte glucocorticoid receptor: preliminary findings in healthy adults

Background

A history of early adverse experiences is an important risk factor for adult psychopathology. Changes in stress sensitivity and functioning of the hypothalamic-pituitary-adrenal (HPA) axis may underlie the association between stress and risk for psychiatric disorders. Preclinical work in rodents has linked low levels of maternal care to increased methylation of the promoter region of the glucocorticoid receptor (GR) gene, as well as to exaggerated hormonal and behavioral responses to stress. Recent studies have begun to examine whether early-life stress leads to epigenetic modifications of the GR gene in humans.

Methods

We examined the degree of methylation of a region of the promoter of the human GR gene (NR3C1) in leukocyte DNA from 99 healthy adults. Participants reported on their childhood experiences of parental behavior, parental death or desertion, and childhood maltreatment. On a separate day, participants completed the dexamethasone/corticotropin-releasing hormone (Dex/CRH) test, a standardized neuroendocrine challenge test.

Results

Disruption or lack of adequate nurturing, as measured by parental loss, childhood maltreatment, and parental care, was associated with increased NR3C1 promoter methylation (p<.05). In addition, NR3C1 promoter methylation was linked to attenuated cortisol responses to the Dex/CRH test (p<.05).

Conclusions

These findings suggest that childhood maltreatment or adversity may lead to epigenetic modifications of the human GR gene. Alterations in methylation of this gene could underlie the associations between childhood adversity, alterations in stress reactivity, and risk for psychopathology.

Neuroimmunoendocrine interactions in patients with recurrent major depression, increased early life stress and long-standing posttraumatic stress disorder symptoms

BACKGROUND

Traumatic events experienced in childhood may lead to psychiatric diseases in adult life, including major depressive disorder (MDD). It remains obscure to what extent early life stress (ELS) is associated with biologically relevant changes in MDD.

OBJECTIVE

We investigated both neuroendocrine and immunological correlates in recurrent MDD with ELS and current posttraumatic stress disorder symptoms.

METHODS

Thirty-eight female MDD patients with or without childhood trauma and 15 healthy controls took part in this study. Salivary cortisol and dehydroepiandrosterone sulfate (DHEAS) were assessed by radioimmunoassays. Peripheral blood mononuclear cells (PBMCs) were isolated and T cell proliferation and cellular sensitivity to steroids and DHEAS were evaluated by colorimetric assays. Th1/Th2 cytokines were assessed by cytometric bead arrays.

RESULTS

MDD patients with or without previous trauma had similarly lower salivary cortisol and DHEAS in parallel with blunted T cell proliferation. PBMCs of depressives were significantly less sensitive to dexamethasone or epinephrine than those of the controls. PBMCs of MDD patients produced significantly lower interleukin (IL)-2, IL-4 and tumor necrosis factor-α levels when compared to healthy controls.

CONCLUSION

We found that a history of ELS did not modify the blunted neuroendocrine and immunological alterations presented by recurrent depressed patients.

A single episode of maternal deprivation impairs the motivation for cocaine in adolescent mice

RATIONALE

Early-life adverse events, like maternal deprivation (MD), have been associated with the later development of mood and anxiety disorders. Scarce data are available describing behavioural and endocrine alterations in maternally deprived (DEP) animals during the periadolescent period. We hypothesize that a single episode of MD early in life would alter reward function and lead to a long-lasting behavioural and neuroendocrine changes during adolescence.

OBJECTIVES

Our aim was to evaluate the effects of a single episode of MD in CD1 adolescent mice (postnatal day 35) on a range of tests for anxiety- and depression-related behaviours (open field, elevated plus maze and tail suspension test). We further assess whether these effects could affect cocaine self-administration behaviour. In order to correlate behavioural and neuroendocrine responses to stress, brain-derived neurotrophic factor (BDNF) levels were assessed in brain structures related to emotional and cognitive processes.

RESULTS

During the cocaine self-administration, the time required for achieving the acquisition criteria was significantly increased and the breaking point values in progressive schedule were significantly reduced in DEP adolescent mice, suggesting impairment in rewarding functions. The behavioural tests also confirm an increase in anxiety- and depression-related behaviours in DEP adolescent mice. The results on BDNF level indicated a decrease in response to MD in amygdala and hippocampus, confirming the behavioural data.

CONCLUSIONS

Our findings demonstrated for the first time that a single episode of early MD can impair the motivation for cocaine consumption in adolescent mice and can be associated with anxiety- and depressive-like behaviour.

Educational paper: Detection of child abuse and neglect at the emergency room

The emergency room (ER) represents the main system entry for crises-based health care visits. It is estimated that 2% to 10% of children visiting the ER are victims of child abuse and neglect (CAN). Therefore, ER personnel may be the first hospital contact and opportunity for CAN victims to be recognised. Early diagnosis of CAN is important, as without early identification and intervention, about one in three children will suffer subsequent abuse. This educational paper provides the reader with an up-to-date and in-depth overview of the current screening methods for CAN at the ER.

CONCLUSION

We believe that a combined approach, using a checklist with risk factors for CAN, a structured clinical assessment and inspection of the undressed patient (called 'top-toe' inspection) and a system of standard referral of all children from parents who attend the ER because of alcohol or drugs intoxication, severe psychiatric disorders or with injuries due to intimate partner violence, is the most promising procedure for the early diagnosis of CAN in the ER setting.

Gender inequitable masculinity and sexual entitlement in rape perpetration South Africa: findings of a cross-sectional study

OBJECTIVE

To describe the prevalence and patterns of rape perpetration in a randomly selected sample of men from the general adult population, to explore factors associated with rape and to describe how men explained their acts of rape.

DESIGN

Cross-sectional household study with a two- stage randomly selected sample of men.

METHODS

1737 South African men aged 18-49 completed a questionnaire administered using an Audio-enhanced Personal Digital Assistant. Multivariable logistic regression models were built to identify factors associated with rape perpetration.

RESULTS

In all 27.6% (466/1686) of men had raped a woman, whether an intimate partner, stranger or acquaintance, and whether perpetrated alone or with accomplices, and 4.7% had raped in the last 12 months. First rapes for 75% were perpetrated before age 20, and 53.9% (251) of those raping, did so on multiple occasions. The logistic regression model showed that having raped was associated with greater adversity in childhood, having been raped by a man and higher maternal education. It was associated with less equitable views on gender relations, having had more partners, and many more gender inequitable practices including transactional sex and physical partner violence. Also drug use, gang membership and a higher score on the dimensions of psychopathic personality, namely blame externalisation and Machiavellian egocentricity. Asked about why they did it, the most common motivations stemmed from ideas of sexual entitlement.

CONCLUSIONS

Perpetration of rape is so prevalent that population-based measures of prevention are essential to complement criminal justice system responses. Our findings show the importance of measures to build gender equity and change dominant ideas of masculinity and gender relations as part of rape prevention. Reducing men's exposure to trauma in childhood is also critically important.

Increased methylation of glucocorticoid receptor gene (NR3C1) in adults with a history of childhood maltreatment: a link with the severity and type of trauma

Childhood maltreatment, through epigenetic modification of the glucocorticoid receptor gene (NR3C1), influences the hypothalamic-pituitary-adrenal axis (HPA axis). We investigated whether childhood maltreatment and its severity were associated with increased methylation of the exon 1(F) NR3C1 promoter, in 101 borderline personality disorder (BPD) and 99 major depressive disorder (MDD) subjects with, respectively, a high and low rate of childhood maltreatment, and 15 MDD subjects with comorbid post-traumatic stress disorder (PTSD). Childhood sexual abuse, its severity and the number of type of maltreatments positively correlated with NR3C1 methylation (P=6.16 × 10(-8), 5.18 × 10(-7) and 1.25 × 10(-9), respectively). In BPD, repetition of abuses and sexual abuse with penetration correlated with a higher methylation percentage. Peripheral blood might therefore serve as a proxy for environmental effects on epigenetic processes. These findings suggest that early life events may permanently impact on the HPA axis though epigenetic modifications of the NR3C1. This is a mechanism by which childhood maltreatment may lead to adulthood psychopathology.

Reduced cerebellar left hemisphere and vermal volume in adults with PTSD from a community sample

BACKGROUND

Traumatic events exposure is a necessary condition for developing posttraumatic stress disorder (PTSD), but not all individuals exposed to the same trauma will develop PTSD. Human studies have suggested that the cerebellum is involved in human fear perception, anticipation, and recollection. In this context, the current study evaluated whether cerebellar volume is associated with PTSD.

METHODS

Eighty-four victims of violence, 42 who fulfilled the DSM-IV-TR criteria for PTSD and 42 resilient controls, were identified through an epidemiologic survey conducted in the city of São Paulo. Subjects were evaluated using the Clinician-Administered PTSD Scale (CAPS), Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI), and Early Trauma Inventory (ETI). All subjects underwent a magnetic resonance imaging (MRI) scan to evaluate their cerebellar hemispheres and vermis.

RESULTS

PTSD subjects had relative smaller left hemisphere (p = 0.04) and vermis (p < 0.01) volumes persisted after controlling for gender, age, and brain volume. In PTSD group, left cerebellar hemisphere volume correlated negatively with PTSD (p = 0.01) and depressive symptoms (p = 0.04). Vermal volume correlated negatively with PTSD symptoms (p < 0.01), early traumatic life events (p < 0.01), depressive symptoms (p = 0.04) and anxiety (p = 0.01).

CONCLUSION

The cerebellum is involved in emotion modulation, and our results suggest that cerebellar volumetric reduction is associated with mood, anxiety and PTSD symptoms. Early traumatic life experiences are related to vermal volume reduction and may be a risk factor for future PTSD development.

Childhood maltreatment and clinical outcomes of bipolar disorder

OBJECTIVE

Adverse life events, especially early trauma, play a major role in the course and expression of bipolar disorder (BD). The aim of this article is to present a systematic review about the impact of childhood trauma on the clinical course of BD.

METHOD

A computer-aided search was performed in Medline, ISI database, EMBASE, PsychInfo, Centre for Reviews and Dissemination, and Databases of Thomson Reuters at April 2011, supplemented by works identified from the reference lists of the first selected papers. Two investigators systematically and independently examined all articles, selecting those according inclusion and exclusion criteria.

RESULTS

Four hundred fifteen articles were identified, of which 19 remained in the review after exclusion criteria were applied. In general, childhood maltreatment predicted worsening clinical course of BD. After assessing the quality of the data and of the measurements, childhood maltreatment can be strongly associated to early onset of disorder, suicidality, and substance abuse disorder in patients with BD.

CONCLUSION

Data suggest that childhood abuse and neglect are risk factors associated with worsening clinical course of BD. The conclusions should be interpreted with caution because all the studies included are cross-sectional and the majority are showing inconsistencies regarding childhood trauma as independent variable and how it is assessed.

Long-term effects of differential early rearing in rhesus macaques: behavioral reactivity in adulthood

Adverse early experiences are associated with a range of deleterious health outcomes in humans, including higher risk for affective disorders. Studies using a long-standing model of nonhuman primate model of early adversity have demonstrated that nursery-reared (NR) monkeys exhibit alterations in multiple aspects of biobehavioral development; however, few studies have evaluated the persistence of socioaffective behavioral changes through adulthood. We evaluated the effects of early rearing experience on adult animals' response to a well-validated assessment of anxiety-like behavior, the human intruder paradigm (HIP). We tested 22 rhesus monkeys who were either nursery-reared (NR) or reared with their mothers (mother-reared; MR). NR monkeys were inhibited in their behavior compared to MR monkeys, with reduced locomotion and exploratory behaviors. NR animals showed a marginal increase in freezing. Together these findings demonstrate that the consequences of differential infant rearing experience on socioaffective behavior persist into adulthood, with evidence of greater inhibition in NR monkeys.

Neuroanatomical changes in a mouse model of early life neglect

Using a novel mouse model of early life neglect and abuse (ENA) based on maternal separation with early weaning, George et al. (BMC Neurosci 11:123, 2010) demonstrated behavioral abnormalities in adult mice, and Bordner et al. (Front Psychiatry 2(18):1-18, 2011) described concomitant changes in mRNA and protein expression. Using the same model, here we report neuroanatomical changes that include smaller brain size and abnormal inter-hemispheric asymmetry, decreases in cortical thickness, abnormalities in subcortical structures, and white matter disorganization and atrophy most severely affecting the left hemisphere. Because of the similarities between the neuroanatomical changes observed in our mouse model and those described in human survivors of ENA, this novel animal model is potentially useful for studies of human ENA too costly or cumbersome to be carried out in primates. Moreover, our current knowledge of the mouse genome makes this model particularly suited for targeted anatomical, molecular, and pharmacological experimentation not yet possible in other species.

Reduced fractional anisotropy in the visual limbic pathway of young adults witnessing domestic violence in childhood

Witnessing domestic violence (WDV) is a traumatic childhood experience associated with increased risk for depression, posttraumatic stress disorder and reduced IQ scores. Specific affects of WDV on brain development have not been assessed. We sought to ascertain whether WDV was associated with abnormalities in white matter (WM) tract integrity using diffusion tensor imaging (DTI). Twenty subjects who witnessed domestic violence (16F/4M, mean age 22.4 ± 2.48 years) but were not physically or sexually abused were compared to 27 healthy controls (19F/8M, 21.9 ± 1.97 years) without exposure to trauma or Axis I and II disorders. DTI images were acquired with a 3T Siemens Trio scanner. Group differences in fractional anisotropy (FA), covaried by age, gender, parental education, perceived financial sufficiency, IQ and degree of exposure to parental verbal aggression were assessed using tract-based spatial statistics (TBSS), which projects FA values onto an alignment-invariant fiber tract representation. FA values in the inferior longitudinal fasciculus of left lateral occipital lobe were significantly lower (P<0.05 corrected for multiple comparison) in the WDV group. FA values correlated inversely with ratings of depression, anxiety, somatization, 'limbic irritability' and neuropsychological measures of processing speed. Measures of radial but not axial diffusivity were affected suggesting alterations in myelination. Degree of FA reduction was associated with duration of witnessing interparental verbal aggression and with exposure between ages 7 and 13 years. The inferior longitudinal fasciculus connects occipital and temporal cortex and is the main component of the visual-limbic pathway that subserves emotional, learning and memory functions that are modality specific to vision. This finding is consistent with the hypothesis that exposure to childhood maltreatment is associated with alterations in fiber pathways that convey the adverse experience to frontal, temporal or limbic regions.

Childhood physical punishment and the onset of drinking problems: evidence from metropolitan China

BACKGROUND

Evidence in support of a suspected causal association linking childhood physical punishment (CPP) and later alcoholic beverage-related disturbances has been found in metropolitan China. Here, the focus shifts to the CPP association with the estimated risk of starting to drink, having the first drinking problem, and transitioning from first drink to the first drinking problem.

METHODS

Data are from the World Mental Health Surveys-metropolitan China study, with representative samples of adult household residents living in two metropolitan cities, Beijing and Shanghai. Recalled information was available for early life experiences (including CPP, other childhood adversities, and parental alcohol and drug problems), as well as the onset age of drinking and drinking problems. Survival analyses were used to estimate the Hazard Ratio. A structural equation modeling approach was used to control for other inter-correlated childhood adversities.

RESULTS

Cox proportional hazards modeling discloses statistically robust associations linking CPP with drinking and drinking problems, as well as more rapid transitions from first drink to first drinking problem, even after accounting for other childhood adversities and parental drinking problems. These associations cannot be attributed to a more general noxious family environment.

CONCLUSIONS

These results lay a foundation for future experimental studies on the possible causal relationship linking CPP with the onset of drinking problems and the transition from drinking to drinking problems.

Stress during development alters anxiety-like behavior and hippocampal neurotransmission in male and female rats

Epidemiological data indicate that early stress increases vulnerability to psychiatric disorders, including anxiety and depression. In the present study we sought to investigate the long-term behavioral and neurochemical consequences of increased and sustained corticosterone levels induced by a 24 h bout of maternal deprivation (DEP) imposed on postnatal day 11 (DEP11). As adults, animals were exposed to the elevated plus maze for assessment of anxiety-like behavior and corticosterone response to this challenge, or decapitated for determination of monoamines and amino acid neurotransmitters content in the hippocampus by HPLC method. The results showed that DEP11 male and female rats displayed increased time in the central hub of the maze and more risk assessment behavior, reflecting increased anxiety-like behavior; in addition, these animals continuously secreted corticosterone in response to the behavioral test until the latest time-point, e.g., 60 min post-stress. In males, maternal deprivation increased aspartate and glutamate levels and reduced taurine levels compared to non-deprived (NDEP) rats. DEP11 females displayed reduced noradrenaline, aspartate and GABA levels compared to NDEP counterparts. These results indicate that maternal deprivation at 11 days of age produced changes in hippocampal neurotransmission that may mediate the increased anxiety-like behavior observed in male and female deprived rats. This article is part of a Special Issue entitled 'Anxiety and Depression'.

Nonsteroidal anti-inflammatory treatment prevents delayed effects of early life stress in rats

BACKGROUND

Early developmental insults can cause dysfunction within parvalbumin (PVB)-containing interneurons in the prefrontal cortex. The neuropsychiatric disorders associated with such dysfunction might involve neuroinflammatory processes. Cyclooxygenase-2 (COX-2) is a key mediator of inflammation and is therefore a potential target for preventive treatment. Here, we investigated whether the developmental trajectories of PVB expression and COX-2 induction in the prelimbic region of the prefrontal cortex are altered after maternal separation stress in male rats.

METHODS

Male rat pups were separated from their mother and littermates for 4 hours/day between postnatal Days 2 and 20. Western blotting and immunohistochemistry were used to analyze PVB and COX-2 expression in the prefrontal cortex and hippocampus. A separate cohort of animals was treated with a COX-2 inhibitor during preadolescence and analyzed for PVB, COX-2, and working memory performance.

RESULTS

We demonstrate that maternal separation causes a reduction of PVB and an increase in COX-2 expression in the prefrontal cortex in adolescence, with concurrent working memory deficits. Parvalbumin was not affected earlier in development. Prophylactic COX-2 inhibition preadolescence prevents PVB loss and improves working memory deficits induced by maternal separation.

CONCLUSIONS

These data are the first to show a preventive pharmacological intervention for the delayed effects of early life stress on prefrontal cortex interneurons and working memory. Our results suggest a possible mechanism for the relationship between early life stress and interneuron dysfunction in adolescence.

Epileptiform activity in alcohol dependent patients and possibilities of its indirect measurement

Background

Alcohol dependence during withdrawal and also in abstinent period in many cases is related to reduced inhibitory functions and kindling that may appear in the form of psychosensory symptoms similar to temporal lobe epilepsy frequently in conditions of normal EEG and without seizures. Because temporal lobe epileptic activity tend to spread between hemispheres, it is possible to suppose that measures reflecting interhemispheric information transfer such as electrodermal activity (EDA) might be related to the psychosensory symptoms.

Methods and Findings

We have performed measurement of bilateral EDA, psychosensory symptoms (LSCL-33) and alcohol craving (ACQ) in 34 alcohol dependent patients and 32 healthy controls. The results in alcohol dependent patients show that during rest conditions the psychosensory symptoms (LSCL-33) are related to EDA transinformation (PTI) between left and right EDA records (Spearman r = 0.44, p<0.01).

Conclusions

The result may present potentially useful clinical finding suggesting a possibility to indirectly assess epileptiform changes in alcohol dependent patients.