The effects of stress on memory and the hippocampus throughout the life cycle: implications for childhood development and aging

Trauma-sensitive school concepts for students with a refugee background: a review of international studies

Children and adolescents with a refugee background are at high risk for traumatization. Once they arrive in safe countries, schools are the institutions where teachers are responsible for caring for them sensitively and competently. Furthermore, schools are organized in learning groups consisting of multiple peers of the same age, which provides excellent opportunities for social learning and experiences of social support. In this respect, schools are the appropriate places where preventive concepts can be applied to students with a refugee background. This systematic review summarizes studies that examine or evaluate existing international concepts of trauma-sensitive schools for supporting traumatized students with a refugee background. Based on N = 41 selected articles, 17 relevant concepts of trauma-sensitive schools were identified. In 35.3% of the concepts, traumatized students with a refugee background are explicitly included in the target group of the concept, while 47.1% of the concepts refer to groups of students with trauma as a result of various adverse childhood experiences, which also occur more frequently within the population of refugee children and adolescents 17.6% of the concepts contain specific adaptations for pupils with a refugee background. The majority of these concepts were developed in the United States. Additional concepts can be reported for Australia, the United Kingdom, Turkey, and Cambodia. Based on available empirical data, no significant effectiveness regarding the researched concepts' effects on academic and other school-related data can be determined. Although some studies indicate positive effects concerning school-related target variables, most of the studies have only limited significance due to inadequate research designs and methodological deficiencies. Therefore, there is a great need for further development, careful implementation, and evaluation of trauma-sensitive concepts in schools, especially for the growing group of refugee students.

Beneficial effects of mindfulness-based intervention on hippocampal volumes and episodic memory for childhood adversity survivors

Background

Adverse Childhood Experience (ACE) has detrimental impacts on neural development, especially hippocampal morphometry. Mindfulness-Based Interventions (MBI) has been shown to induce adaptive hippocampal changes especially at the subiculum. The present study aims to investigate the effects of MBI on subiculum volumes among ACE survivors, as well as the effects on episodic memory as a probe into hippocampal functionality.

Methods

We analyzed anatomical MRI data and performance indices from an episodic memory task called the Mnemonic Similarity Task (MST) collected from a randomized controlled longitudinal study that compared an 8-week MBI (N = 20) to an active control condition of Stress Management Education (SME) (N = 19). FreeSurfer 6.0 was used for automated hippocampal subfield segmentation and volumetric estimation.

Results

Significant group differences were observed with the volumetric changes of the right whole hippocampus and right subiculum. Only the MBI group showed improved pattern separation capability from MST, which was associated with stress reduction and right subiculum volumetric changes.

Limitations

Modest sample size. MST task was performed outside of MRI.

Conclusions

These findings suggest beneficial effects of MBI for hippocampal volumes and episodic memory, while highlighting the importance of the subiculum for MBI-induced neural and cognitive changes. The subiculum's known role in inhibitory control was interpreted as a potential mechanism for it to exhibit MBI-induced volumetric changes, which sheds light on the potential neural underpinnings of mindfulness meditation for reducing stress reactivity among ACE survivors.

Sex-specific effects of neonatal paternal deprivation on microglial cell density in adult California mouse (Peromyscus californicus) dentate gyrus

Adverse early-life experiences are risk factors for psychiatric disease development, resulting in stress-related neuronal modeling and neurobehavioral changes. Stressful experiences modulate the immune system, contributing to neuronal damage in higher cortical regions, like the hippocampus. Moreover, early-life stressors dysregulate the function of microglia, the resident immune cells of the brain, in the developing hippocampus. Paternal deprivation, an early-life stressor in many biparental species, facilitates sex-dependent inhibitions in hippocampal plasticity, but parental contributors to these sex-specific outcomes are unknown. Also, neurobiological mechanisms contributing to impairments in hippocampal neuroplasticity are less known. Thus, our goals were to 1) determine whether parental behavior is altered in maternal females following removal of the paternal male, 2) assess the effects of paternal deprivation on dentate gyrus (DG) volume and microglia proliferation, and 3) determine if early-life experimental handling mitigates sex-specific reductions in DG cell survival. California mice were born to multiparous breeders and reared by both parents (biparental care) or by their mother alone (i.e., father removed on postnatal day 1; paternal deprivation). One cohort of offspring underwent offspring retrieval tests for eight days beginning on postnatal day 2. On PND 68, these offspring (and a second cohort of mice without behavioral testing) were euthanized and brains visualized for bromodeoxyuridine (BrdU) and neuron-specific class III beta-tubulin (TuJ-1) or ionized calcium binding adaptor molecule 1 (Iba1). While mate absence did not impair maternal retrieval, paternal deprivation reduced DG volume, but Iba1+ cell density was only higher in paternally-deprived females. Neither sex or paternal deprivation significantly altered the number of BrdU+ or Tuj1+ cells in the DG - an absence of a reduction in cell survival may be related to daily handing during early offspring retrieval tests. Together, these data suggest that paternal deprivation impairs hippocampal plasticity; however, sex and early environment may influence the magnitude of these outcomes.

The effects of stress across the lifespan on the brain, cognition and mental health: A UK biobank study

Repeated overstimulation of the stress response system, caused by exposure to prolonged highly stressful experiences, is thought to affect brain structure, cognitive ability, and mental health. We tested the effects of highly stressful experiences during childhood and adulthood using data from the UK Biobank, a large-scale national health and biomedical study with over 500,000 participants. To do this, we defined four groups with high or low levels of childhood and/or adulthood stress. We then used T1-and diffusion-weighted MRI data to assess the macrostructure of grey matter and microstructure of white matter within limbic brain regions, commonly associated with the stress response. We also compared executive function and working memory between these groups. Our findings suggest that in females, higher levels of Childhood stress were associated with reduced connectivity within the posterior thalamic radiation and cingulum of the hippocampus. In males however, higher levels of Adulthood stress is associated with similar changes in brain microstructure in the posterior thalamic radiation and cingulum of the hippocampus. High stress in Childhood and Adulthood was associated with decreases in executive function and working memory in both males and females. Stress across the lifespan was also positively associated with the number of diagnosed mental health problems, with a stronger effect in females than in males. Finally, our findings also suggest that cognitive and mental health outcomes due to stress may be mediated by the sex specific stress related changes in brain microstructure. Together our findings demonstrate clear links between stress at distinct phases of the lifespan, changes in measures of brain microstructure, impairments in cognitive abilities and negative mental health outcomes.

Integrative Brain Dynamics in Childhood Bullying Victimization: Cognitive and Emotional Convergence Associated With Stress Psychopathology

Bullying victimization is a form of psychological stress that is associated with poor outcomes in the areas of mental health and learning. Although the emotional maladjustment and memory impairment following interpersonal stress are well documented, the mechanisms of complex cerebral dysfunctions have neither been outlined nor studied in depth in the context of childhood bullying victimization. As a contribution to the cross-disciplinary field of developmental psychology and neuroscience, we review the neuropathophysiology of early life stress, as well as general psychological stress to synthesize the data and clarify the versatile dynamics within neuronal networks linked to bullying victimization. The stress-induced neuropsychological cascade and associated cerebral networks with a focus on cognitive and emotional convergence are described. The main findings are that stress-evoked neuroendocrine reactivity relates to neuromodulation and limbic dysregulation that hinder emotion processing and executive functioning such as semantic cognition, cognitive flexibility, and learning. Developmental aspects and interacting neural mechanisms linked to distressed cognitive and emotional processing are pinpointed and potential theory-of-mind nuances in targets of bullying are presented. The results show that childhood stress psychopathology is associated with a complex interplay where the major role belongs to, but is not limited to, the amygdala, fusiform gyrus, insula, striatum, and prefrontal cortex. This interplay contributes to the sensitivity toward facial expressions, poor cognitive reasoning, and distress that affect behavioral modulation and emotion regulation. We integrate the data on major brain dynamics in stress neuroactivity that can be associated with childhood psychopathology to help inform future studies that are focused on the treatment and prevention of psychiatric disorders and learning problems in bullied children and adolescents.

Hippocampal volume, FKBP5 genetic risk alleles, and childhood trauma interact to increase vulnerability to chronic multisite musculoskeletal pain

Chronic multisite musculoskeletal pain (CMP) is common and highly morbid. However, vulnerability factors for CMP are poorly understood. Previous studies have independently shown that both small hippocampal brain volume and genetic risk alleles in a key stress system gene, FKBP5, increase vulnerability for chronic pain. However, little is known regarding the relationship between these factors and CMP. Here we tested the hypothesis that both small hippocampal brain volume and FKBP5 genetic risk, assessed using the tagging risk variant, FKBP5rs3800373, increase vulnerability for CMP. We used participant data from 36,822 individuals with available genetic, neuroimaging, and chronic pain data in the UK Biobank study. Although no main effects were observed, the interaction between FKBP5 genetic risk and right hippocampal volume was associated with CMP severity (β = -0.020, p_raw = 0.002, p_adj = 0.01). In secondary analyses, severity of childhood trauma further moderated the relationship between FKBP5 genetic risk, right hippocampal brain volume, and CMP (β = -0.081, p = 0.016). This study provides novel evidence that both FKBP5 genetic risk and childhood trauma moderate the relationship between right hippocampal brain volume and CMP. The data increases our understanding of vulnerability factors for CMP and builds a foundation for further work assessing causal relationships that might drive CMP development.

Exposure to the troubles in Northern Ireland, memory functioning, and social activity engagement: results from NICOLA

We investigated the potential impact of a cohort traumatic exposure, the Troubles in Northern Ireland, on memory functioning in later life, and the potential moderating effect of social activity engagement. Using data from 6571 participants aged 60 + in the Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA) cohort, we used a structural equation modelling framework to explore associations between traumatic exposure during the Troubles and memory functioning. As expected, social activity engagement was positively associated with memory functioning, β = .102. Traumatic exposure was also positively associated with memory functioning, β = .053. This association was stronger at low levels of social activity engagement; among those with higher levels, there was little association, interaction β = - 0.054. The positive association between traumatic exposure during the Troubles and memory functioning was not moderated by the age at which the exposures occurred (based on analysis of a subsample with available data), interaction β = - 0.015. We conclude that superior memory functioning was associated with higher levels of traumatic exposure during the Troubles, particularly among those with lower levels of social activity engagement, and regardless of the age at which the exposures occurred. Future longitudinal analyses are required to build on these results, which potentially have implications for life-course epidemiology, in relation to critical periods for traumatising experiences.

Association Between Posttraumatic Stress Disorder and Epigenetic Age Acceleration in a Sample of Twins

OBJECTIVE

Posttraumatic stress disorder (PTSD) has been related to accelerated biological aging processes, but objective evidence for this association is limited. DNA methylation (DNAm) age acceleration is a novel measure of biological aging that may help clarify if PTSD is related to biological aging processes. We aim to examine whether PTSD is associated with biological aging using a comprehensive set of DNAm age acceleration markers and to what extent the unshared environment contributes to the association.

METHODS

Using a cross-sectional co-twin control study design, we investigated the association of the clinical diagnosis and symptom severity of PTSD with six measurements of DNAm age acceleration based on epigenome-wide data derived from peripheral blood lymphocytes of 296 male twins from the Vietnam Era Twin Registry.

RESULTS

Twins with current PTSD had significantly advanced DNAm age acceleration compared with twins without PTSD for five of six measures of DNAm age acceleration. Across almost all measures of DNAm age acceleration, twins with current PTSD were "epigenetically older" than their twin brothers without PTSD: estimated differences ranged between 1.6 (95% confidence interval = 0.0-3.1) and 2.7 (95% confidence interval = 0.5-4.8) biological age year-equivalents. A higher Clinician-Administered PTSD Scale score was also associated with a higher within-pair DNAm age acceleration. Results remained consistent after adjustment for behavioral and cardiovascular risk factors.

CONCLUSIONS

PTSD is associated with epigenetic age acceleration, primarily through unshared environmental mechanisms as opposed to genetic or familial factors. These results suggest that PTSD is related to systemic processes relevant to biological aging.

Adverse childhood experiences and domain-specific cognitive function in a population-based study of older adults in rural South Africa

Research on early life adversity and later-life cognitive function is conflicting, with little evidence from low-income settings. We investigated associations between adverse childhood experiences and cognitive function in an older population who grew up under racial segregation during South African apartheid. Data were from 1,871 adults aged 40-79 in the population-representative "Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa" in 2015. The adverse childhood experiences were having a parent unemployed for > 6 months; having parents who argued or fought often; having a parent who drank excessively, used drugs, or had mental health problems; and physical abuse from parents. Executive function, language, visuospatial ability, and memory were assessed with the Oxford Cognitive Screen-Plus, a validated cognitive assessment designed for low-income, low-literacy settings. We estimated associations between adverse childhood experiences and latent cognitive domain z-scores using multiple-indicator, multiple-cause structural equation models. Childhood adversities were reported by 15% (parental unemployment for > 6 months), 25% (parents argued or fought often), 25% (a parent drank excessively, used drugs, or had mental health problems), and 35% (physical abuse from parent) of respondents. They were not associated with cognition, except that having a parent who drank excessively, used drugs, or had mental health problems was associated with lower memory z-scores (-0.07; 95% CI [-0.13, -0.01]). This is one of the first investigations into later-life cognitive outcomes associated with early adversity in a population with a historical context of pervasive trauma, and suggests that later-life memory may be vulnerable to early adversity. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Are Gender Differences in DSM-5 PTSD Symptomatology Explained by Sexual Trauma?

Although many studies have assessed gender differences in posttraumatic stress disorder (PTSD) prevalence, few examine individual PTSD symptoms (PTSSs). Hypothesizing that trauma differences explain many gender differences in symptomatology, this is the first known study to adjust PTSSs for trauma type, and to compare gender differences in those with sexual traumas. Using a cross-sectional survey methodology in a sample of adult outpatients (n = 775), we examined gender, trauma type, PTSSs, suicide, alcohol, and tobacco. Among those with trauma (n = 483), women generally had more severe symptoms than men, but after adjusting for trauma type, only physical reactivity (p = .0002), excessive startle (p = .0005), external avoidance (p = .0007), internal avoidance (p = .0008), psychological reactivity (p = .0009), and suicide attempts (p = .001) remained significantly worse among women, whereas men more commonly reported alcohol problems (p = .007). Among those with PTSD (n = 164), there were no significant PTSS gender differences. Those with sexual trauma had worse symptoms (particularly amnesia) compared with non-sexual trauma (p < .0001 for PTSD diagnosis and total severity), including within each gender. Among those with sexual trauma (n = 157), men had worse recklessness (p = .004) and more commonly reported tobacco (p = .02), whereas women more commonly attempted suicide (p = .02) and had worse avoidance (p = .04). However, when isolating the effects of sexual trauma beyond other traumas, there were no significant symptom difference-in-differences between genders. Our findings suggest that, while women have higher PTSD rates, men with PTSD present similarly. In addition, while women have higher sexual trauma rates, men may have similarly severe responses. Most gender differences in PTSD presentation appear to be explained by trauma type, particularly women having higher rates of sexual trauma. We discuss potential biopsychosocial explanations.

A developmental model of addictions: integrating neurobiological and psychodynamic theories through the lens of attachment

Although substance use and abuse may impact brain and behavior, it is still unclear why some people become addicted while others do not. Neuroscientific theories explain addiction as a series of between- and within-system neuroadaptations that lead to an increasingly dysregulating cycle, affecting reward, motivation, and executive control systems. In contrast, psychoanalysis understands addiction through a relational perspective wherein there is an underlying failure in affect regulation, a capacity shaped early developmentally. Considering recent findings suggesting the neurobiological overlap of addiction and attachment, it may be possible to integrate both perspectives into a developmental model through the lens of attachment. The goal of the present review is to evaluate the value of neurobiological and psychodynamic perspectives to inform our understanding of addiction, particularly substance-use disorders.

Effect of acute alarm odor exposure and biological sex on generalized avoidance and glutamatergic signaling in the hippocampus of Wistar rats

Post-traumatic stress disorder (PTSD) is characterized by the development of paradoxical memory disturbances including intrusive memories and amnesia for specific details of the traumatic experience. Despite evidence that women are at higher risk to develop PTSD, most animal research has focused on the processes by which male rodents develop adaptive fear memory. As such, the mechanisms contributing to sex differences in the development of PTSD-like memory disturbances are poorly understood. In this investigation, we exposed adult male and female Wistar rats to the synthetic alarm odor 2,4,5-trimethylthiazole (TMT) to assess development of generalized fear behavior and rapid modulation of glutamate uptake and signaling cascades associated with hippocampus-dependent long-term memory. We report that female Wistar rats exposed to alarm odor exhibit context discrimination impairments relative to TMT-exposed male rats, suggesting the intriguing possibility that females are at greater risk in developing generalized fear memories. Mechanistically, alarm odor exposure rapidly modulated signaling cascades consistent with activation of the CREB shut-off cascade in the male, but not the female hippocampus. Moreover, TMT exposure dampened glutamate uptake and affected expression of the glutamate transporter, GLT-1 in the hippocampus. Taken together, these results provide evidence for rapid sex-dependent modulation of CREB signaling in the hippocampus by alarm odor exposure which may contribute to the development of generalized fear.

Effect of experience, equipment and fire actions in psychophysiological response and memory of soldiers in actual underground operations

The present study aimed to analyze the effect of underground operations on the psychophysiological and memory response of soldiers taking into consideration experience, the use of nocturne vision systems and previous combat actions on the psychophysiological response. Seventy participants were recruited and divided in four groups, three experimental groups with different experimental conditions, SNFV (Soldiers No-Fire Night-Vision), SFV (Soldiers Fire Night-Vision), SNFNV (Soldiers No-Fire No Night-Vision), and one control group, CNFV (Control No-Fire Night-Vision). We analyzed modifications in psychophysiological and memory response pre and post an underground operation. The underground operation produced a significant increase (p < 0.05) in blood lactate, blood oxygen saturation, rated perceived exertion, heart rate, cognitive and somatic anxiety and sympathetic modulation in all groups. Groups with higher stress values scored higher incorrect items in the memory post mission questionnaire. The higher psychophysiological activation correlated positively with cognitive impairment and lower memory. We concluded that an underground operation produced an increase in psychophysiological activation and a negative effect on memory, being modulated by previous training and experience. The lack of special equipment as night vision systems in underground operations induced similar stress response than prior combat actions, decreasing conciseness of time.

Mindfulness as an Intervention for Recalling Information from a Lecture as a Measure of Academic Performance in Higher Education

Higher education students experience heightened levels of stress and anxiety, and report experiencing negative thoughts and emotions, which influence information retention and recall. In a randomized experiment, we assigned participants to either a mindfulness meditation or an audiobook listening condition, and recorded the information recalled from a previously attended lecture, which was controlled for in subsequent analyses for trait resiliency and trait mindfulness. Participants placed in the mindfulness meditation condition recalled significantly more information than participants who were placed in the audiobook listening condition, even when controlling for resiliency and mindfulness. Future directions are suggested in an attempt to expand the literature and research around higher education, mindfulness and individual differences.

Structural and Functional Brain Abnormalities Associated With Exposure to Different Childhood Trauma Subtypes: A Systematic Review of Neuroimaging Findings

Background: Childhood trauma subtypes sexual abuse, physical abuse, emotional maltreatment, and neglect may have differential effects on the brain that persist into adulthood. A systematic review of neuroimaging findings supporting these differential effects is as yet lacking. Objectives: The present systematic review aims to summarize the findings of controlled neuroimaging trials regarding long-term differential effects of trauma subtypes on the human brain. Methods: A systematic literature search was performed using the PubMed and PsycINFO databases from January 2017 up to and including January 2018. Additional papers were identified by a manual search in the reference lists of selected papers and of relevant review articles retrieved by the initial database search. Studies were then assessed for eligibility by the first author. Only original human studies directly comparing neuroimaging findings of exposed and unexposed individuals to well-defined emotional, physical or sexual childhood maltreatment while controlling for the effects of other subtypes were included. A visual summary of extracted data was made for neuroimaging modalities for which comparison between trauma subtypes was feasible, taking the studies' numbers and sample sizes into account. Results: The systematic literature search yielded 25 publications. Sexual abuse was associated with structural deficits in the reward circuit and genitosensory cortex and amygdalar hyperreactivity during sad autobiographic memory recall. Emotional maltreatment correlated with abnormalities in fronto-limbic socioemotional networks. In neglected individuals, white matter integrity and connectivity were disturbed in several brain networks involved in a variety of functions. Other abnormalities, such as reduced frontal cortical volume, were common to all maltreatment types. Conclusions: There is some evidence for long-term differential effects of trauma subtypes on the human brain. The observed alterations may result from both protective adaptation of and damage to the brain following exposure to threatening life events. Though promising, the current evidence is incomplete, with few brain regions and neuroimaging modalities having been investigated in all subtypes. The comparability of the available evidence is further limited by the heterogeneity of study populations regarding gender, age and comorbid psychopathology. Future neuroimaging studies should take this potentially differential role of childhood trauma subtypes into account.

A Survey of English Sixth Formers' Knowledge of Early Brain Development

Objectives To ascertain the knowledge of young people aged 16 to 19 of early brain development and their attitudes towards the care of babies and preschool children. Design Cross-sectional, school- and college-based survey including all sixth form students present on the days of data collection. The survey instrument comprised forced-choice questions in four sections: Demographics, Perceptions and Understanding of Early Childhood Development, Parental Behaviors to Support Early Brain development, and Resource Needs and Usage. Setting Two sixth form schools and one sixth form college in three towns of varying affluence in the West Midlands of the United Kingdom. Method The survey was mounted online and completed by 905 students who returned it directly to the researcher. Results Most students knew that tobacco, alcohol, and drugs are hazardous in pregnancy, and many recognized the impact of maternal stress on fetal brain development. Many believed that babies can be "spoiled" and did not appreciate the importance of reading to babies and of the relationship between play and early brain development. A significant minority thought that physical activity and a healthy diet have little impact on young children's development. Respondents said they would turn firstly to their parents for advice on baby care rather than professionals. Conclusion Young people need educating about parenting activities that support the all-round healthy development of infants. The importance of a healthy diet, physical activity, reading, and play should be included in sixth form curricula and antenatal classes. Consideration should be given to educating grandparents because of their influence on new parents.

ADHD symptoms in healthy adults are associated with stressful life events and negative memory bias

Stressful life events, especially Childhood Trauma, predict ADHD symptoms. Childhood Trauma and negatively biased memory are risk factors for affective disorders. The association of life events and bias with ADHD symptoms may inform about the etiology of ADHD. Memory bias was tested using a computer task in N = 675 healthy adults. Life events and ADHD symptoms were assessed using questionnaires. The mediation of the association between life events and ADHD symptoms by memory bias was examined. We explored the roles of different types of life events and of ADHD symptom clusters. Life events and memory bias were associated with overall ADHD symptoms as well as inattention and hyperactivity/impulsivity symptom clusters. Memory bias mediated the association of Lifetime Life Events, specifically Childhood Trauma, with ADHD symptoms. Negatively biased memory may be a cognitive marker of the effects of Childhood Trauma on the development and/or persistence of ADHD symptoms.

Effects of childhood trauma exposure and cortisol levels on cognitive functioning among breast cancer survivors

Cognitive functioning difficultiesin breast cancer patients receiving chemotherapy are common, but not all women experience these impairments. Exposure to childhood trauma may impair cognitive functioning following chemotherapy, and these impairments may be mediated by dysregulation of hypothalamic-pituitary-adrenal (HPA) axis function and cortisol slope. This study evaluated the association between childhood trauma exposure, cortisol, and cognition in a sample of breast cancer survivors. 56 women completed measures of trauma exposure (the Traumatic Events Survey), salivary cortisol, and self-reported cognitive functioning (the Functional Assessment of Cancer Therapy - Cognitive). We examined correlations between childhood trauma exposure and cognitive functioning, then used linear regression to control for factors associated with cognition (age, education, time since chemotherapy, depression, anxiety, and insomnia), and the MacArthur approach to test whether cortisol levels mediated the relationship between trauma and cognitive functioning. 57.1% of the sample had experienced at least one traumatic event in childhood, with 19.6% of the sample witnessing a serious injury, 17.9% experiencing physical abuse, and 14.3% experiencing sexual abuse. Childhood trauma exposure and cognitive functioning were moderately associated (r=-0.29). This association remained even when controlling for other factors associated with cognition; the final model explained 47% of the variance in cognitive functioning. The association between childhood trauma and cognitive functioning was mediated by steeper cortisol slope (partial r=0.35, p=0.02). Childhood trauma exposure is associated with self-reported cognitive functioning among breast cancer survivors and is mediated by cortisol dysregulation. Trauma should be considered, among other factors, in programs aiming to address cognition in this population.

Early life stress leads to developmental and sex selective effects on performance in a novel object placement task

Disruptions in early life care, including neglect, extreme poverty, and trauma, influence neural development and increase the risk for and severity of pathology. Significant sex disparities have been identified for affective pathology, with females having an increased risk of developing anxiety and depressive disorder. However, the effects of early life stress (ELS) on cognitive development have not been as well characterized, especially in reference to sex specific impacts of ELS on cognitive abilities over development. In mice, fragmented maternal care resulting from maternal bedding restriction, was used to induce ELS. The development of spatial abilities were tracked using a novel object placement (NOP) task at several different ages across early development (P21, P28, P38, P50, and P75). Male mice exposed to ELS showed significant impairments in the NOP task compared with control reared mice at all ages tested. In female mice, ELS led to impaired NOP performance immediately following weaning (P21) and during peri-adolescence (P38), but these effects did not persist into early adulthood. Prior work has implicated impaired hippocampus neurogenesis as a possible mediator of negative outcomes in ELS males. In the hippocampus of behaviorally naïve animals there was a significant decrease in expression of Ki-67 (proliferative marker) and doublecortin (DCX-immature cell marker) as mice aged, and a more rapid developmental decline in these markers in ELS reared mice. However, the effect of ELS dissipated by P28 and no main effect of sex were observed. Together these results indicate that ELS impacts the development of spatial abilities in both male and female mice and that these effects are more profound and lasting in males.

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ELS leads to sex differences in spatial memory abilities in mice.

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Female mice show impaired performance that resolve prior to adolescence.

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Male mice show persistent impairments across early life.

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Effects are restricted to spatial abilities and not other task dimensions.

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Effects are not related to markers of proliferation and differentiation in hippocampus.

PTSD symptom severity relates to cognitive and psycho-social dysfunctioning - a study with Congolese refugees in Uganda

Background: In the ongoing conflict in the Democratic Republic of the Congo (DRC), civilians have been heavily exposed to traumatic stressors. Traumatizing experiences cumulatively heighten the risk for trauma-related disorders, and with it affect cognitive and psycho-social functioning. Objectives: We aimed at investigating the association between trauma-related disorders and cognitive and psycho-social functioning and hypothesized that PTSD symptom severity would negatively correlate with executive functioning, working memory and psycho-social functioning in everyday life. Method: In total, 323 Congolese refugees (mean age: 31.3 years) who arrived in the Ugandan Nakivale refugee settlement after January 2012 were assessed regarding their exposure to traumatic events, PTSD symptom severity (posttraumatic symptom scale interview), executive functioning (Tower of London), working memory performance (Corsi block tapping task) and psycho-social dysfunctioning (Luo functioning scale). Results: Hierarchical regression analyses indicated a significant negative association between PTSD symptom severity and working memory (β = -0.32, p < 0.001), as well as executive functions (β = -0.19, p = 0.003). Furthermore, the impairment of psycho-social functioning in everyday life was positively related with PTSD symptom severity (β = 0.70, p < 0.001), and negatively with executive functioning (β = -0.15, p = 0.003). However, working memory performance was not significantly related to psycho-social dysfunctioning (β = 0.09, p > 0.05). Conclusion: Trauma survivors not only suffer from the core PTSD symptoms but also from impaired cognitive functioning. PTSD symptom severity seems furthermore to be related to impaired psycho-social functioning. Our findings suggest that trauma-related mental health problems may heighten the risk for poverty and lack of prospect and further aggravate the consequences of war and conflict.

The Role of Odor-Evoked Memory in Psychological and Physiological Health

This article discusses the special features of odor-evoked memory and the current state-of-the-art in odor-evoked memory research to show how these unique experiences may be able to influence and benefit psychological and physiological health. A review of the literature leads to the conclusion that odors that evoke positive autobiographical memories have the potential to increase positive emotions, decrease negative mood states, disrupt cravings, and reduce physiological indices of stress, including systemic markers of inflammation. Olfactory perception factors and individual difference characteristics that would need to be considered in therapeutic applications of odor-evoked-memory are also discussed. This article illustrates how through the experimentally validated mechanisms of odor-associative learning and the privileged neuroanatomical relationship that exists between olfaction and the neural substrates of emotion, odors can be harnessed to induce emotional and physiological responses that can improve human health and wellbeing.

Chronic occupational exposures can influence the rate of PTSD and depressive disorders in first responders and military personnel

Background

First responders and military personnel experience rates of post-traumatic stress disorder (PTSD) far in excess of the general population. Although exposure to acute traumatic events plays a role in the genesis of these disorders, in this review, we present an argument that the occupational and environmental conditions where these workers operate are also likely contributors.

Presentation of the hypothesis

First responders and military personnel face occupational exposures that have been associated with altered immune and inflammatory activity. In turn, these physiological responses are linked to altered moods and feelings of well-being which may provide priming conditions that compromise individual resilience, and increase the risk of PTSD and depression when subsequently exposed to acute traumatic events. These exposures include heat, smoke, and sleep restriction, and physical injury often alongside heavy physical exertion. Provided the stimulus is sufficient, these exposures have been linked to inflammatory activity and modification of the hypothalamic–pituitary axis (HPA), offering a mechanism for the high rates of PTSD and depressive disorders in these occupations.

Testing the hypothesis

To test this hypothesis in the future, a case–control approach is suggested that compares individuals with PTSD or depressive disorders with healthy colleagues in a retrospective framework. This approach should characterise the relationships between altered immune and inflammatory activity and health outcomes. Wearable technology, surveys, and formal experimentation in the field will add useful data to these investigations.

Implications of the hypothesis

Inflammatory changes, linked with occupational exposures in first responders and military personnel, would highlight the need for a risk management approach to work places. Risk management strategies could focus on reducing exposure, ensuring recovery, and increasing resilience to these risk contributors to minimise the rates of PTSD and depressive disorders in vulnerable occupations.

Chemotherapy-induced neurotoxicity in pediatric solid non-CNS tumor patients: An update on current state of research and recommended future directions

Neurocognitive sequelae are known to be induced by cranial radiotherapy and central-nervous-system-directed chemotherapy in childhood Acute Lymphoblastic Leukemia (ALL) and brain tumor patients. However, less evidence exists for solid non-CNS-tumor patients. To get a better understanding of the potential neurotoxic mechanisms of non-CNS-directed chemotherapy during childhood, we performed a comprehensive literature review of this topic. Here, we provide an overview of preclinical and clinical studies investigating neurotoxicity associated with chemotherapy in the treatment of pediatric solid non-CNS tumors. Research to date suggests that chemotherapy has deleterious biological and psychological effects, with animal studies demonstrating histological evidence for neurotoxic effects of specific agents and human studies demonstrating acute neurotoxicity. Although the existing literature suggests potential neurotoxicity throughout neurodevelopment, research into the long-term neurocognitive sequelae in survivors of non-CNS cancers remains limited. Therefore, we stress the critical need for neurodevelopmental focused research in children who are treated for solid non-CNS tumors, since they are at risk for potential neurocognitive impairment.

Alteration in Memory and Electroencephalogram Waves with Sub-acute Noise Stress in Albino Rats and Safeguarded by Scoparia dulcis

Background:

Noise stress has different effects on memory and novelty and the link between them with an electroencephalogram (EEG) has not yet been reported.

Objective:

To find the effect of sub-acute noise stress on the memory and novelty along with EEG and neurotransmitter changes.

Materials and Methods:

Eight-arm maze (EAM) and Y-maze to analyze the memory and novelty by novel object test. Four groups of rats were used: Control, control treated with Scoparia dulcis extract, noise exposed, and noise exposed which received Scoparia extract.

Results:

The results showed no marked difference observed between control and control treated with Scoparia extract on EAM, Y-maze, novel object test, and EEG in both prefrontal and occipital region, however, noise stress exposed rats showed significant increase in the reference memory and working memory error in EAM and latency delay, triad errors in Y-maze, and prefrontal and occipital EEG frequency rate with the corresponding increase in plasma corticosterone and epinephrine, and significant reduction in the novelty test, and significant reduction in the novelty test, amplitude of prefrontal, occipital EEG, and acetylcholine.

Conclusion:

These noise stress induced changes in EAM, Y-maze, novel object test, and neurotransmitters were significantly prevented when treated with Scoparia extract and these changes may be due to the normalizing action of Scoparia extract on the brain, which altered due to noise stress.

SUMMARY

Noise stress exposure causes EEG, behavior, and neurotransmitter alteration in the frontoparietal and occipital regions mainly involved in planning and recognition memory

Only the noise stress exposed animals showed the significant alteration in the EEG, behavior, and neurotransmitters

However, these noise stress induced changes in EEG behavior and neurotransmitters were significantly prevented when treated with Scoparia extract

These changes may be due to the normalizing action of Scoparia dulcis (adoptogen) on the brain which altered by noise stress.

Abbreviations used: EEG: Electroencephalogram, dB: Decibel, EPI: Epinephrine, ACH: Acetylcholine, EAM: Eight-arm maze

Mitochondrial DNA copy number is reduced in male combat veterans with PTSD

INTRODUCTION

Mitochondrial abnormalities may be involved in PTSD, although few studies have examined this. Mitochondrial DNA copy number (mtDNAcn) in blood cells is an emerging systemic index of mitochondrial biogenesis and function. The present study assessed mtDNAcn in male combat-exposed veterans with PTSD compared to those without PTSD as well as its correlation with clinical scales.

METHODS

mtDNAcn was assessed with a TaqMan multiplex assay in granulocytes of 43 male combat veterans with (n=43) or without (n=44) PTSD. Twenty of the PTSD subjects had co-morbid major depressive disorder (MDD). The Clinician Administered PTSD Scale (CAPS), the Positive and Negative Affect Schedule (PANAS), the Early Trauma Inventory (ETI) and the Beck Depression Inventory II (BDI-II) were used for the clinical assessments. All analyses were corrected for age and BMI.

RESULTS

mtDNAcn was significantly lower in subjects with PTSD (p<0.05). Within the PTSD group, those with moderate PTSD symptom severity had relatively higher mtDNAcn than those with mild or severe symptoms (p<0.01). Within the PTSD group, mtDNAcn was positively correlated with PANAS positive subscale ratings (p<0.01) but was not significantly correlated with PANAS negative subscale, ETI or BDI-II ratings.

DISCUSSION

This study provides the first evidence of: (i) a significant decrease of mtDNAcn in combat PTSD, (ii) a possible "inverted-U" shaped relationship between PTSD symptom severity and mtDNAcn within PTSD subjects, and (iii) a direct correlation of mtDNAcn with positive affectivity within PTSD subjects. Altered mtDNAcn in PTSD may reflect impaired energy metabolism, which might represent a novel aspect of its pathophysiology.

Psychiatric disorders and leukocyte telomere length: Underlying mechanisms linking mental illness with cellular aging

Many psychiatric illnesses are associated with early mortality and with an increased risk of developing physical diseases that are more typically seen in the elderly. Moreover, certain psychiatric illnesses may be associated with accelerated cellular aging, evidenced by shortened leukocyte telomere length (LTL), which could underlie this association. Shortened LTL reflects a cell's mitotic history and cumulative exposure to inflammation and oxidation as well as the availability of telomerase, a telomere-lengthening enzyme. Critically short telomeres can cause cells to undergo senescence, apoptosis or genomic instability, and shorter LTL correlates with poorer health and predicts mortality. Emerging data suggest that LTL may be reduced in certain psychiatric illnesses, perhaps in proportion to exposure to the psychiatric illnesses, although conflicting data exist. Telomerase has been less well characterized in psychiatric illnesses, but a role in depression and in antidepressant and neurotrophic effects has been suggested by preclinical and clinical studies. In this article, studies on LTL and telomerase activity in psychiatric illnesses are critically reviewed, potential mediators are discussed, and future directions are suggested. A deeper understanding of cellular aging in psychiatric illnesses could lead to re-conceptualizing them as systemic illnesses with manifestations inside and outside the brain and could identify new treatment targets.

The role of stress and fear in the development of mental disorders

The most common pathologic manifestation of fear is posttraumatic stress disorder (PTSD). Developing PTSD is closely related with predisposing factors such as genes and early traumatic experiences. In PTSD, enhanced fear learning and poor extinction are common. Fear is manifested through autonomic responses and persistent memories of the traumatic event. These manifestations are related to stress responses modulated by the hypothalamic-pituitary-adrenal axis. This article evaluates the role of fear and stress in the course of PTSD. Findings on fear learning and extinction are presented in order to guide future treatments of patients with PTSD.

The effect of childhood trauma on spatial cognition in adults: a possible role of sex

Although animal evidence indicates that early life trauma results in pervasive hippocampal deficits underlying spatial and cognitive impairment, visuo-spatial data from adult humans with early childhood adversity are lacking. We administered 4 tests of visuo-spatial ability from the Cambridge Neuorpsychological Test Automated Battery (CANTAB) to adults with a history of childhood trauma (measured by the Childhood Trauma Questionnaire) and a matched sample of healthy controls (trauma/control = 27/28). We observed a significant effect of trauma history on spatial/pattern learning. These effects could not be accounted for by adverse adult experiences, and were sex-specific, with prior adversity improving performance in men but worsening performance in women, relative to controls. Limitations include the small sample size and reliance of our study design on a retrospective, self report measure. Our results suggest that early adversity can lead to specific and pervasive deficits in adult cognitive function.

Epigenetics, stress, and their potential impact on brain network function: a focus on the schizophrenia diatheses

The recent sociodevelopmental cognitive model of schizophrenia/psychosis is a highly influential and compelling compendium of research findings. Here, we present logical extensions to this model incorporating ideas drawn from epigenetic mediation of psychiatric disease, and the plausible effects of epigenetics on the emergence of brain network function and dysfunction in adolescence. We discuss how gene-environment interactions, effected by epigenetic mechanisms, might in particular mediate the stress response (itself heavily implicated in the emergence of schizophrenia). Next, we discuss the plausible relevance of this framework for adolescent genetic risk populations, a risk group characterized by vexing and difficult-to-explain heterogeneity. We then discuss how exploring relationships between epigenetics and brain network dysfunction (a strongly validated finding in risk populations) can enhance understanding of the relationship between stress, epigenetics, and functional neurobiology, and the relevance of this relationship for the eventual emergence of schizophrenia/psychosis. We suggest that these considerations can expand the impact of models such as the sociodevelopmental cognitive model, increasing their explanatory reach. Ultimately, integration of these lines of research may enhance efforts of early identification, intervention, and treatment in adolescents at-risk for schizophrenia.

Bridging intimate partner violence and the human brain: a literature review

Past studies mainly focused on the physical and structural brain injuries in women survivors with a history of intimate partner violence (IPV), but little attention has been given to the biological impact and cognitive dysfunction resulting from such psychological stress. In this article, we aim to establish the connection between IPV and the brain by reviewing current literature examining (1) the biological mechanisms linking IPV, stress, and the brain; (2) the functional and anatomical considerations of the brain in abused women; and (3) the abused women's behavioral responses to IPV, including fear, pain, and emotion regulation, by utilizing functional neuroimaging. The major significance of this study is in highlighting the need to advance beyond self-reports and to obtain scientific evidence of the neurological impact and cognitive dysfunction in abused women with a history of IPV, an area in which current literature remains at a descriptive level.

How ineffective family environments can compound maldevelopment of critical thinking skills in childhood abuse survivors

The high stress of childhood abuse is associated with neurobiological detriments to executive function. Child abuse survivors may also be cognitively and relationally disadvantaged as a result of being raised in emotionally impoverished families that lack cohesion, organization, flexibility, self-expression, and moral and ethical values and fail to provide opportunities for effective learning. A review of literature demonstrates how dysfunctional family of origin environments common to child abuse survivors, concomitant with the extreme stress of overt acts of abuse, can act as a barrier to the development of higher-order critical thinking skills. The article concludes by discussing ramifications of critical thinking skill deficits in child abuse survivors and highlights the importance of integrating and prioritizing critical thinking skills training in treatment.

Dietary variation of protein–carbohydrate: Effect on hypothalamic and hippocampal GABA–glutamate in relation to aging

Dietary protein variation has been found to alter brain regional neurochemistry with aging. In the present investigation, we studied the effect of short-term treatment of protein-carbohydrate variable diet to rat on hypothalamic and hippocampal gamma-amino butyric acid (GABA)-glutamate metabolism with increase of age. Exposure of male albino rats with diet containing normal protein (20%)-normal carbohydrate (68%) increased GABA metabolism and decreased glutamate metabolism in both hypothalamus and hippocampus with the increase of age. GABA-glutamate metabolism of rats having low protein (8%)-high carbohydrate (80%) diet for short-term period (STP), was activated in young age (3 months) and decreased in old age (18 months) in both the brain regions. On the contrary, intake of high protein (50%)-low carbohydrate (38%) diet under similar condition decreased GABA-glutamate metabolism in both hypothalamus and hippocampus of young brain and increased only in hypothalamus of aged brain. In hippocampus of aged brain the same diet decreased glutamate metabolism without changing its GABA metabolism. These results suggest that an age-associated change in GABA-glutamate metabolism depends on the amount of dietary protein and carbohydrate and also on the brain region.

Impact of childhood stress on psychopathology

OBJECTIVE

Advances in our knowledge of mental disorder (MD) genetics have contributed to a better understanding of their pathophysiology. Nonetheless, several questions and doubts persist. Recent studies have focused on environmental influences in the development of MDs, and the advent of neuroscientific methodologies has provided new perspectives. Early life events, such as childhood stress, may affect neurodevelopment through mechanisms such as gene-environment interactions and epigenetic regulation, thus leading to diseases in adulthood. The aim of this paper is to review the evidence regarding the role of the environment, particularly childhood stress, in the pathophysiology of MD.

METHODOLOGY

We reviewed articles that evaluated environmental influences, with a particular focus on childhood trauma, brain morphology, cognitive functions, and the development of psychopathology and MD.

RESULTS AND CONCLUSION

MRI studies have shown that exposure to trauma at an early age can result in several neurostructural changes, such as the reduction of the hippocampus and corpus callosum. Cognitive performance and functioning are also altered in this population. Finally, childhood stress is related to an increased risk of developing MD such as depression, bipolar disorder, schizophrenia and substance abuse. We conclude that there is robust evidence of the role of the environment, specifically adverse childhood experiences, in various aspects of MD.

Impact of early vs. late childhood early life stress on brain morphometrics

Previous studies of early life trauma suggest that in addition to its emotional impact, exposure to early life stress (ELS) is associated with alterations in brain structure. However, little attention has been devoted to the relationship between emotional processing and brain integrity as a function of age of ELS onset. In the present study we examined whether ELS onset in older ages of youth rather than younger ages is associated with smaller limbic and basal ganglia volumes as measured by magnetic resonance imaging (MRI). We hypothesized that later age of manifestation during youth is associated with smaller volumetric morphology in limbic and basal ganglia volumes in adulthood. A total of 173 individuals were divided into three groups based on the age of self-reported ELS. The three groups included individuals only experiencing early childhood ELS (1 month-7 years, n = 38), those only experiencing later childhood ELS (8 years -17 years, n = 59), and those who have not experienced ELS (n = 76). Anterior cingulate cortex (ACC), hippocampus, amygdala, insula and caudate volumes were measured using a T1-weighted MRI. Analyses confirmed that later childhood ELS was associated with volumetric reductions in the ACC and insula volumes, while ELS experienced between the ages of 1 month and 7 years was not associated with lower brain volumes in these regions. The results may reflect the influence of more fully developed emotional processing of ELS on the developing brain and reinforce a body of research implicating both the ACC and insula in neuropsychiatric disorders and emotional regulation.

Somatic drugs for psychiatric diseases: aspirin or simvastatin for depression?

The evolution in the understanding of the neurobiology of most prevalent mental disorders such as major depressive disorder (MDD), bipolar disorder or schizophrenia has not gone hand in hand with the synthesis and clinical use of new drugs that would represent a therapeutic revolution such as that brought about by selective serotonin reuptake inhibitors (SSRIs) or atypical antipsychotics. Although scientists are still a long way from understanding its true aetiology, the neurobiological concept of depression has evolved from receptor regulation disorder, to a neurodegenerative disorder with a hippocampal volume decrease with the controversial reduction in neurotrophins such as BDNF, to current hypotheses that consider depression to be an inflammatory and neuroprogressive process. As regards antidepressants, although researchers are still far from knowing their true mechanism of action, they have gone from monoaminergic hypotheses, in which serotonin was the main protagonist, to emphasising the anti-inflammatory action of some of these drugs, or the participation of p11 protein in their mechanism of action.In the same way, according to the inflammatory hypothesis of depression, it has been proposed that some NSAIDS such as aspirin or drugs like simvastatin that have an anti-inflammatory action could be useful in some depressive patients. Despite the fact that there may be some data to support their clinical use, common sense and the evidence advise us to use already tested protocols and wait for the future to undertake new therapeutic strategies.

Therapeutic approaches to age-associated neurocognitive disorders

The United Nations projects that the number of individuals with dementia in developed countries alone will be approximately 36,7 million by the year 2050. International recognition of the significant emotional and economic burden of Alzheimer's disease has been matched by a dramatic increase in the development of pharmacological and nonpharmacological approaches to this illness in the past decade. Changing demographics have underscored the necessity to develop similar approaches for the remediation of the cognitive impairment associated with more benign syndromes, such as mild cognitive impairment (MCI) and age-associated cognitive decline (AACD). The present article aims to provide an overview of the most current therapeutic approaches to age-associated neurocognitive disorders. Additionally, it discusses the conceptual and methodological issues that surround the design, implementation, and interpretation of such approaches.

Stress-induced anhedonia is associated with an increase in Alzheimer's disease-related markers

BACKGROUND AND PURPOSE

Stress is believed to be associated with the development of neuropsychiatric disorders, including Alzheimer's disease (AD). We have studied mechanisms implicated in vulnerability to stress and the relationship with changes in AD-related markers.

EXPERIMENTAL APPROACH

Anhedonia induced by a chronic mild stress (CMS) procedure, applied for 6 weeks, was used to select rats vulnerable or resistant to stress. Sucrose intake, the Porsolt forced swimming test and cognitive deficits in the novel object recognition test (NORT) were used to characterize vulnerable and resilient rats. The antidepressant venlafaxine (20 mg·kg(-1) p.o.) or saline was administered daily during the last 2 weeks of CMS. Biochemical markers affected by stress, PKB, ERK and synaptophysin, and those associated with AD, amyloid β-protein (Aβ), β-secretase (BACE1) and τ phosphorylation, were measured in the hippocampus.

KEY RESULTS

After CMS, 40% of rats were resistant to the development of anhedonia (CMS-resistant to stress), whereas the remaining were responsive [CMS-anhedonic (CMSA)]. Only CMSA rats displayed significant increases in immobility time in the forced swimming test and cognitive deficits in the NORT, and significant decreases in synaptophysin, phosphorylated PKB and phosphorylated ERK1/2 expression in the hippocampus. Increased levels of Aβ40, BACE1 and τ phosphorylation were also found only in CMSA rats. All these effects in CMSA rats were reverted by treatment with venlafaxine.

CONCLUSIONS AND IMPLICATIONS

Vulnerability to stress might constitute a risk factor for the development of AD, and pharmacological treatment with venlafaxine may represent a therapeutic strategy for the treatment of stress-related disorders, including AD.

Childhood Maltreatment and Prospectively Observed Quality of Early Care as Predictors of Antisocial Personality Disorder Features

Few studies have evaluated the separate contributions of maltreatment and ongoing quality of parent-child interaction to the etiology of antisocial personality features using a prospective longitudinal design. 120 low-income young adults (aged 18-23) were assessed for extent of ASPD features on the Structured Clinical Interview for Diagnosis-Axis II, for presence of maltreatment on the Conflict Tactics Scale, Traumatic Experiences Scale, and Adult Attachment Interview, and for referral in infancy to parent-infant clinical services. Fifty-six of these families had been studied longitudinally since the first year of life. In infancy, attachment disorganization and disrupted mother-infant interaction were assessed; in middle childhood, disorganized-controlling attachment behaviors were reliably rated. In kindergarten and second grade, behavior problems were assessed by teacher report. In cross-sectional analyses, maltreatment was significantly associated with ASPD features but did not account for the independent effect of early referral to parent-infant services on ASPD features. In longitudinal analyses, maternal withdrawal in infancy predicted the extent of ASPD features twenty years later, independently of childhood abuse. In middle childhood, disorganized attachment behavior and maladaptive behavior at school added to prediction of later ASPD features. Antisocial features in young adulthood have precursors in the minute-to-minute process of parent-child interaction beginning in infancy.

Early life stress exacerbates cognitive dysfunction induced by d-amphetamine: amelioration by valproic acid

It has been demonstrated that experiences taking place early in life have a profound influence on brain development, interacting with the genetic background and determining differences in the vulnerability to the onset of bipolar disorder when the individual is exposed to a second adverse event later in life. Here, we investigated the effects of exposure to an early adverse life event (maternal deprivation) and to a later adverse life event [D-amphetamine (AMPH)] on cognition in an animal model of mania. We have previously demonstrated that that repeated AMPH exposure produces severe and persistent cognitive impairment, which was more pronounced when the animals were maternal deprived, suggesting that the early adverse life event could be potentiating the effects of the exposure to the second adverse life event later in life. Here, we show that valproic acid ameliorated the cognitive deficits induced by AMPH, but it was not effective when the animals were exposed to both stressors: maternal deprivation and AMPH treatment.

Microglia in the normally aged hippocampus

The hippocampus plays important roles in the regulation and combination of short and long term memory and spatial navigation with other brain centers. Aging is accompanied by a functional decline of the hippocampus and degenerative disease. Microglia are major immune cells in the central nervous system and response to degenerative changes in the aged brain. In this respect, functional and morphological changes of the hippocampus have been closely related to microglial changes during normal aging with or without disease. Therefore, in this review, we discuss morphological and functional changes of the hippocampus and microglia in the aging brain.

Increased cortisol level: a possible link between climacteric symptoms and cardiovascular risk factors

OBJECTIVE

Vasomotor symptoms may increase the risk for cardiovascular diseases through still elusive mechanisms. Increased cortisol release may favor atherosclerosis. In this study, we tested whether vasomotor and psychological symptoms are associated with an increase in cortisol levels.

METHODS

A cross-sectional investigation on women in early menopause enrolled consecutively between January and June 2009 was conducted. This study was set at a menopause outpatient service at University Hospital. Participants included 85 healthy women who were 6 months to 5 years postmenopause. The 24-hour urinary cortisol level and Greene Climacteric Scale scores were evaluated. Anthropometric parameters and fasting blood samples for the determination of high-density lipoprotein (HDL) cholesterol, total cholesterol, triglycerides, glucose, and insulin levels were measured. Body mass index, waist-to-hip ratio, and homeostatic model assessment of insulin resistance were calculated. The relation between Greene Climacteric Scale scores and 24-hour urinary cortisol level and between 24-hour urinary cortisol level and lipid levels or insulin resistance was determined.

RESULTS

The Greene Climacteric Scale score for climacteric symptoms (coefficient of regression [CR], 1.343; 95% CI, 0.441-2.246) and body mass index (CR, 4.469; 95% CI, 1.259-7.678) explained 32.5% and 10.3%, respectively, of the variance in 24-hour urinary cortisol level (r = 0.428; P = 0.0003). Twenty-four-hour urinary cortisol level was inversely related to HDL-cholesterol level (CR, -0.065; 95% CI, -0.114 to -0.017; r = 0.283; P = 0.009) and was related to waist girth (CR, 0.685; 95% CI, 0.306-1.063) and homeostatic model assessment of insulin resistance (CR, 0.097; 95% CI, 0.032-0.162; r = 0.510; P = 0.0001).

CONCLUSIONS

In early postmenopausal women, the Greene Climacteric Scale score is associated with increased 24-hour urinary cortisol level. Increased cortisol level is associated with known risk factors for cardiovascular disease, such as insulin resistance and decreased HDL-cholesterol level.

Early life stress decreases hippocampal BDNF content and exacerbates recognition memory deficits induced by repeated D-amphetamine exposure

Adverse experiences early in life may have profound influences on brain development, for example, determining alterations in response to psychostimulant drugs, an increased risk of developing a substance abuse disorder, and individual differences in the vulnerability to neuropsychiatric disorders later in life. Here, we investigated the effects of exposure to an early adverse life event, maternal deprivation, combined with repeated d-amphetamine (AMPH) administration in adulthood, on recognition memory and brain-derived neurotrophic factor (BDNF) levels in rats' brain and serum. Rats were exposed to one of the following maternal rearing conditions from postnatal days 1 to 14: non-deprived (ND) or deprived (D). In adulthood, both groups received injections of saline (SAL) or AMPH (2.0mg/kg, i.p.) for 7 days. In Experiment I (performed 24h after the last AMPH injection), AMPH induced long-term memory (LTM) impairments in ND and D groups. The D+AMPH group also presented short-term memory (STM) impairments, indicating that the effects of AMPH on memory were more pronounced when the animals where maternally deprived. The group exposed to D+SAL (SAL) showed only LTM impairments. In Experiment II (performed 8 days after the last injection), AMPH detrimental effects on memory persisted in ND and D groups. BDNF levels were decreased in the hippocampus of D+SAL rats. In conclusion, AMPH produces severe and persistent recognition memory impairments that were more pronounced when the animals were maternally deprived, suggesting that an early adverse life event may increase the vulnerability of cognitive function to exposure to a psychostimulant later in life.

Auditory memory decrements, without dissimulation, among patients with major depressive disorder

Questions have been raised about whether poor performance on memory tasks by individuals with major depressive disorder (MDD) might be the result of poor or variable effort or disease-related disruption of neural circuits supporting memory functions. The present study examined performance on a measure of task engagement and on an auditory memory task among 45 patients with MDD (M age = 47.82, SD = 19.55) relative to 32 healthy controls (HC; M age = 51.03, SD = 22.09). One-hundred percent of HC and MDD volunteers performed above the threshold for adequate effort on a formal measure of task engagement. The MDD subjects performed significantly more poorly than the HC subjects on an auditory learning and memory test. The present results suggest that auditory memory difficulties do occur among those with MDD and that decrements in performance in this group may be related to factors other than lack of effort.