Socioeconomic status and the developing brain

Childhood trauma and cognitive function in first-episode affective and non-affective psychosis

BACKGROUND

A history of childhood trauma is reportedly more prevalent in people suffering from psychosis than in the general population. Childhood trauma has also been linked to cognitive abnormalities in adulthood, and cognitive abnormalities, in turn, are one of the key clinical features of psychosis. Therefore, this study investigated whether there was a relationship between childhood trauma and cognitive function in patients with first-episode psychosis. The potential impact of diagnosis (schizophrenia or affective psychosis) and gender on this association was also examined.

METHODS

Data were available for 138 first-episode psychosis patients and 138 geographically-matched controls recruited from a catchment area based organisation. History of childhood trauma was obtained using the Childhood Experience of Care and Abuse Questionnaire. Cognitive function was assessed through a comprehensive and standardised neuropsychological test battery.

RESULTS

A history of childhood trauma was associated with worse cognitive performances, predominantly in affective psychoses, and in male patients. No association between a history of childhood trauma and cognition was found amongst female patients, or female controls.

CONCLUSIONS

The results need replication, but underline the necessity of investigating biological and psychosocial mechanisms underlying these subjects' sensitivity to the negative effect of childhood stress.

Total and regional brain volumes in a population-based normative sample from 4 to 18 years: the NIH MRI Study of Normal Brain Development

Using a population-based sampling strategy, the National Institutes of Health (NIH) Magnetic Resonance Imaging Study of Normal Brain Development compiled a longitudinal normative reference database of neuroimaging and correlated clinical/behavioral data from a demographically representative sample of healthy children and adolescents aged newborn through early adulthood. The present paper reports brain volume data for 325 children, ages 4.5-18 years, from the first cross-sectional time point. Measures included volumes of whole-brain gray matter (GM) and white matter (WM), left and right lateral ventricles, frontal, temporal, parietal and occipital lobe GM and WM, subcortical GM (thalamus, caudate, putamen, and globus pallidus), cerebellum, and brainstem. Associations with cross-sectional age, sex, family income, parental education, and body mass index (BMI) were evaluated. Key observations are: 1) age-related decreases in lobar GM most prominent in parietal and occipital cortex; 2) age-related increases in lobar WM, greatest in occipital, followed by the temporal lobe; 3) age-related trajectories predominantly curvilinear in females, but linear in males; and 4) small systematic associations of brain tissue volumes with BMI but not with IQ, family income, or parental education. These findings constitute a normative reference on regional brain volumes in children and adolescents.

Life-course socioeconomic position and incidence of dementia and cognitive impairment without dementia in older Mexican Americans: results from the Sacramento area Latino study on aging

There have been few investigations of the link between changes in life-course socioeconomic position (SEP) and cognitive decline or incidence of dementia. The authors examined the impact of changes in life-course SEP on incidence of dementia and cognitive impairment but not dementia (CIND) over a decade of follow-up. Participants of Mexican origin (n = 1,789) were members of the Sacramento Area Latino Study on Aging cohort. Incidence of dementia/CIND was ascertained by using standard diagnostic criteria. SEP indicators at 3 life stages (childhood, adulthood, and midlife) were used to derive a measure of cumulative SEP (range, 0 to 8) and SEP mobility. Nearly 24% of the sample maintained a low SEP throughout life. Hazard ratios and 95% confidence intervals were computed from Cox proportional hazards regression models. In fully adjusted models, participants with a continuously high SEP had lower hazard ratios for dementia/CIND compared with those with a continuously low SEP at all 3 life stages (hazard ratio = 0.49, 95% confidence interval: 0.24, 0.98; P = 0.04). In age-adjusted models, participants experienced a 16% greater hazard of dementia/CIND with every 1-unit increase in cumulative SEP disadvantage across the life course (hazard ratio = 1.16, 95% confidence interval: 1.01, 1.33; P = 0.04). Early exposures to social disadvantage may increase the risk of late-life dementia.

Association between income and the hippocampus

Facets of the post-natal environment including the type and complexity of environmental stimuli, the quality of parenting behaviors, and the amount and type of stress experienced by a child affects brain and behavioral functioning. Poverty is a type of pervasive experience that is likely to influence biobehavioral processes because children developing in such environments often encounter high levels of stress and reduced environmental stimulation. This study explores the association between socioeconomic status and the hippocampus, a brain region involved in learning and memory that is known to be affected by stress. We employ a voxel-based morphometry analytic framework with region of interest drawing for structural brain images acquired from participants across the socioeconomic spectrum (n = 317). Children from lower income backgrounds had lower hippocampal gray matter density, a measure of volume. This finding is discussed in terms of disparities in education and health that are observed across the socioeconomic spectrum.

Socioeconomic position and cognitive function in the Seychelles: a life course analysis

OBJECTIVE

Poorer socioeconomic conditions early in life have been linked with memory, attention and learning deficits in adulthood, as well as with specific areas of educational achievement. It remains unclear, however, whether these distal associations are mediated by more current socioeconomic factors. In this study, we sought to confirm the relation between early-life socioeconomic position (SEP) and adult cognitive function, and to examine potential mediation by contemporaneous SEP.

METHODS

Data from 463 young adults from the Main Cohort of the Seychelles Child Development Study were analyzed using subtests of the Cambridge Neurological Test Automated Battery and the Woodcock Johnson Test of Scholastic Achievement in relation to maternal Hollingshead Social Status Index scores at study enrollment (infancy), follow-up at 107 months, and follow-up at 17 years.

RESULTS

Findings include evidence of a link between infant-period SEP and 17-year memory, which was not mediated by childhood and 17-year SEP. Verbal and mathematical achievement at 17 years was associated with SEP at all points in the life course.

CONCLUSIONS

SEP at different points during the young-adult life course may affect different cognitive domains later in life, which may provide targets for societal investment in ensuring adequate family resources throughout childhood and adolescence.

Socioeconomic status, a forgotten variable in lateralization development

Socioeconomic status (SES), a variable combining income, education, and occupation, is correlated with a variety of social health outcomes including school dropout rates, early parenthood, delinquency, and mental illness. Several studies conducted in the 1970s and 1980s largely failed to report a relationship between SES and hemispheric asymmetry as measured by lateral differences in dichotic listening, tactile dot enumeration, and visual emotion and word recognition. However, none of the studies used asymmetry measures correcting for both ceiling and floor effects in accuracy, raising the question of whether lower and higher SES groups were comparable. Here the published data are reanalyzed using a laterality coefficient that corrects for such effects. The results are consistent across studies in revealing reduced lateralization in lower SES groups. Developmentally, this finding is consistent with either maturation delay or reduced functional specialization, or both. Suggestions are made for further research that include the use of behavioral asymmetry measures to screen tasks for structural and functional brain imaging.

Language outcomes following risk-adapted treatments for tumors located within the posterior fossa

The language skills of 4 children treated for tumors involving the cerebellum and/or fourth ventricle with risk-adapted treatments were compared, as a group, with performance of a group of control children (n = 20). The language skills of the individual cases were also profiled. At the group level, language skill failed to differentiate the 2 groups of children. At an individual level, however, only 1 of the 4 children treated with risk-adapted treatments presented with intact language skills. Variable language profiles were identified in the remaining 3 children. The presence of hydrocephaly was a consistent factor in reduced language outcomes. The findings highlight the importance of prospective language monitoring.

Socioeconomic gradients and child development in a very low income population: evidence from Madagascar

Our objectives were to document and examine socioeconomic gradients across a comprehensive set of child development measures in a population living in extreme poverty, and to interpret these gradients in light of findings from the neuroscience literature. We assessed a nationally representative sample of 3-6-year-old children (n = 1332) from 150 communities of Madagascar using standard tests of development. We found that children whose families were in the top wealth quintile or whose mothers had secondary education performed significantly better across almost all measures of cognitive and language development and had better linear growth compared with children of women in the lowest wealth quintile or women with no education. These differences between children of low and high socioeconomic position were greatest for receptive language, working memory, and memory of phrases. The mean difference in the scores between children in the highest and lowest socioeconomic status categories doubled between age 3 and age 6, and the biggest gaps across socioeconomic position by age 6 were in receptive language and sustained attention. Our results suggest that even within the context of extreme poverty, there are strong associations between family socioeconomic status and child development outcomes among preschool children, and that the language and executive function domains exhibit the largest gradients.

Psychological perspectives on pathways linking socioeconomic status and physical health

Low socioeconomic status (SES) is a reliable correlate of poor physical health. Rather than treat SES as a covariate, health psychology has increasingly focused on the psychobiological pathways that inform understanding why SES is related to physical health. This review assesses the status of research that has examined stress and its associated distress, and social and personal resources as pathways. It highlights work on biomarkers and biological pathways related to SES that can serve as intermediate outcomes in future studies. Recent emphasis on the accumulation of psychobiological risks across the life course is summarized and represents an important direction for future research. Studies that test pathways from SES to candidate psychosocial pathways to health outcomes are few in number but promising. Future research should test integrated models rather than taking piecemeal approaches to evidence. Much work remains to be done, but the questions are of great health significance.

Family socioeconomic status and child executive functions: the roles of language, home environment, and single parenthood

The association between family socioeconomic status (SES) and child executive functions is well-documented. However, few studies have examined the role of potential mediators and moderators. We studied the independent and interactive associations between family SES and single parenthood to predict child executive functions of inhibitory control, cognitive flexibility, and working memory and examined child expressive language abilities and family home environment as potential mediators of these associations. Sixty families from diverse SES backgrounds with a school-age target child (mean [SD] age = 9.9 [0.96] years) were evaluated. Child executive functioning was measured using a brief battery. The quality of the home environment was evaluated using the Home Observation for the Measurement of the Environment inventory. Family SES predicted the three child executive functions under study. Single parent and family SES were interactively associated with children's inhibitory control and cognitive flexibility; such that children from low SES families who were living with one parent performed less well on executive function tests than children from similarly low SES who were living with two parents. Parental responsivity, enrichment activities and family companionship mediated the association between family SES and child inhibitory control and working memory. This study demonstrates that family SES inequalities are associated with inequalities in home environments and with inequalities in child executive functions. The impact of these disparities as they unfold in the lives of typically developing children merits further investigation and understanding.

Variability in frontotemporal brain structure: the importance of recruitment of African Americans in neuroscience research

Background

Variation in brain structure is both genetically and environmentally influenced. The question about potential differences in brain anatomy across populations of differing race and ethnicity remains a controversial issue. There are few studies specifically examining racial or ethnic differences and also few studies that test for race-related differences in context of other neuropsychiatric research, possibly due to the underrepresentation of ethnic minorities in clinical research. It is within this context that we conducted a secondary data analysis examining volumetric MRI data from healthy participants and compared the volumes of the amygdala, hippocampus, lateral ventricles, caudate nucleus, orbitofrontal cortex (OFC) and total cerebral volume between Caucasian and African-American participants. We discuss the importance of this finding in context of neuroimaging methodology, but also the need for improved recruitment of African Americans in clinical research and its broader implications for a better understanding of the neural basis of neuropsychiatric disorders.

Methodology/Principal Findings

This was a case control study in the setting of an academic medical center outpatient service. Participants consisted of 44 Caucasians and 33 ethnic minorities. The following volumetric data were obtained: amygdala, hippocampus, lateral ventricles, caudate nucleus, orbitofrontal cortex (OFC) and total cerebrum. Each participant completed a 1.5 T magnetic resonance imaging (MRI). Our primary finding in analyses of brain subregions was that when compared to Caucasians, African Americans exhibited larger left OFC volumes (F _1,68 = 7.50, p = 0.008).

Conclusions

The biological implications of our findings are unclear as we do not know what factors may be contributing to these observed differences. However, this study raises several questions that have important implications for the future of neuropsychiatric research.

Genetics of white matter development: a DTI study of 705 twins and their siblings aged 12 to 29

White matter microstructure is under strong genetic control, yet it is largely unknown how genetic influences change from childhood into adulthood. In one of the largest brain mapping studies ever performed, we determined whether the genetic control over white matter architecture depends on age, sex, socioeconomic status (SES), and intelligence quotient (IQ). We assessed white matter integrity voxelwise using diffusion tensor imaging at high magnetic field (4-Tesla), in 705 twins and their siblings (age range 12-29; 290 M/415 F). White matter integrity was quantified using a widely accepted measure, fractional anisotropy (FA). We fitted gene-environment interaction models pointwise, to visualize brain regions where age, sex, SES and IQ modulate heritability of fiber integrity. We hypothesized that environmental factors would start to outweigh genetic factors during late childhood and adolescence. Genetic influences were greater in adolescence versus adulthood, and greater in males than in females. Socioeconomic status significantly interacted with genes that affect fiber integrity: heritability was higher in those with higher SES. In people with above-average IQ, genetic factors explained over 80% of the observed FA variability in the thalamus, genu, posterior internal capsule, and superior corona radiata. In those with below-average IQ, however, only around 40% FA variability in the same regions was attributable to genetic factors. Genes affect fiber integrity, but their effects vary with age, sex, SES and IQ. Gene-environment interactions are vital to consider in the search for specific genetic polymorphisms that affect brain integrity and connectivity.

Neuroscience and the future of early childhood policy: moving from why to what and how

There is a need for greater synergy between advances in neuroscience and the formulation of innovative policies to improve life outcomes for children experiencing significant adversity. Translational developmental neuroscience can inform new theories of change to catalyze more effective interventions that lead to a more productive and healthier society.

Neural basis of social status hierarchy across species

Social status hierarchy is a ubiquitous principle of social organization across the animal kingdom. Recent findings in social neuroscience reveal distinct neural networks associated with the recognition and experience of social hierarchy in humans, as well as modulation of these networks by personality and culture. Additionally, allelic variation in the serotonin transporter gene is associated with prevalence of social hierarchy across species and cultures, suggesting the importance of the study of genetic factors underlying social hierarchy. Future studies are needed to determine how genetic and environmental factors shape neural systems involved in the production and maintenance of social hierarchy across ontogeny and phylogeny.

Socioeconomic status and the brain: mechanistic insights from human and animal research

Human brain development occurs within a socioeconomic context and childhood socioeconomic status (SES) influences neural development--particularly of the systems that subserve language and executive function. Research in humans and in animal models has implicated prenatal factors, parent-child interactions and cognitive stimulation in the home environment in the effects of SES on neural development. These findings provide a unique opportunity for understanding how environmental factors can lead to individual differences in brain development, and for improving the programmes and policies that are designed to alleviate SES-related disparities in mental health and academic achievement.

Parental education predicts corticostriatal functionality in adulthood

Socioeconomic disadvantage experienced in early development predicts ill health in adulthood. However, the neurobiological pathways linking early disadvantage to adult health remain unclear. Lower parental education-a presumptive indicator of early socioeconomic disadvantage-predicts health-impairing adult behaviors, including tobacco and alcohol dependencies. These behaviors depend, in part, on the functionality of corticostriatal brain systems that 1) show developmental plasticity and early vulnerability, 2) process reward-related information, and 3) regulate impulsive decisions and actions. Hence, corticostriatal functionality in adulthood may covary directly with indicators of early socioeconomic disadvantage, particularly lower parental education. Here, we tested the covariation between parental education and corticostriatal activation and connectivity in 76 adults without confounding clinical syndromes. Corticostriatal activation and connectivity were assessed during the processing of stimuli signaling monetary gains (positive feedback [PF]) and losses (negative feedback). After accounting for participants' own education and other explanatory factors, lower parental education predicted reduced activation in anterior cingulate and dorsomedial prefrontal cortices during PF, along with reduced connectivity between these cortices and orbitofrontal and striatal areas implicated in reward processing and impulse regulation. In speculation, adult alterations in corticostriatal functionality may represent facets of a neurobiological endophenotype linked to socioeconomic conditions of early development.

School performance in a cohort of children with CNS inflammatory demyelination

BACKGROUND

Acute CNS inflammatory demyelination in childhood may induce permanent cognitive impairment. However, there has been no epidemiological assessment of prognostic factors for school performance in a cohort of children with such a disease.

METHODS

The cohort consisted of 344 children from the French "KIDSEP" neuropediatric cohort with at least one clinically defined attack of CNS inflammatory demyelination occurring before the age of 16 years, and with at least two years of follow-up (inclusion from 1990 to 2003, follow-up until June 2007). We used multivariate survival analysis (Cox model) to evaluate the prognostic value for grade retention between the start of elementary school ( approximately 6 years of age) and the end of high school ( approximately 17-18 years of age), of variables related to both the socioeconomic status of the parents and the characteristics of the disease at onset.

RESULTS

The cohort was monitored for a mean of 8.0+/-3.4 years. Grade retention after disease onset was recorded for 151 patients (43.9%). The risk of grade retention was significantly higher for boys, children from families with lower social status and poorer housing conditions, children over the age of 11 years at disease onset and children suffering optic neuritis or brainstem dysfunction at the first attack or irreversible disability, even if only moderate, following the first attack.

CONCLUSIONS

The risk factors for poor school performance are related to low socioeconomic status and to factors predictive of a relapsing severe course of the disease, leading to the diagnosis of multiple sclerosis.

Socioeconomic status and psychological function in children with chromosome 22q11.2 deletion syndrome: implications for genetic counseling

The purpose of this study is to examine the association between parental socio-economic status (SES) and childhood neurocognition and behavior in children with chromosome 22q11.2 deletion syndrome (22q11DS). Although undoubtedly, the deletion of genes in the 22q11.2 interval is primarily responsible for the psychological manifestations, little is known about the role of the environment in either mitigating or contributing to these problems. We examined the association of parental socio-economic status (SES) with cognition and behavior in children with 22q11DS (n = 65) and matched healthy control subjects (n = 52), since SES is a component of family resources. We found that in children with 22q11DS, higher SES correlated with better overall functioning (p < .01) and social skills (p < .01), and less frequent oppositional defiant behavior (p < .001). These findings were in contrast to the control subjects in whom SES correlated with cognition and achievement, but not behavior. Our results indicate that environmental factors influence the behavioral phenotype in children with 22q11DS, providing a framework for developing appropriate interventions. As such, genetic counseling for families with 22q11DS may include consideration of family resources and inclusion of other health professionals, such as social workers, to explore with the family available social supports and resources.

Factors in sensory processing of prosody in schizotypal personality disorder: an fMRI experiment

INTRODUCTION

Persons diagnosed with schizophrenia demonstrate deficits in prosody recognition. To examine prosody along the schizophrenia spectrum, antipsychotic-naïve schizotypal personality disorder (SPD) subjects and healthy control subjects were compared. It was hypothesized that SPD subjects would perform more poorly; with cognitive and demographic factors contributing to the poor performance. The superior temporal gyrus (STG) was selected as the region-of-interest (ROI) given its known abnormalities in SPD and its important role in the processing of prosody.

METHODS

SPD and healthy comparison (HC) subjects were matched on age, IQ, and parental social-economic status (PSES). Cognitive measures included the Speech Sound Perception Test (SSPT) to examine phonological processing (SPD=68, HC=74) and the Verbal Fluency task to examine executive functioning (SPD=129, HC=138). The main experiment was a novel fMRI task of prosody identification using semantically neutral sentences spoken with emotional prosody (SPD=16, HC=13). Finally, volumetric measurement of the superior temporal sulcus (STS), a key region for processing prosody, and partially overlapping with the STG, was performed (SPD=30, HC=30).

RESULTS

Phonological processing and executive functioning were both impaired in SPD subjects compared with HC subjects. Contrary to the prediction, SPD subjects, as a group, were similar to HC subjects in terms of correctly indentifying the emotion conveyed and reaction time. Within the SPD group, prosody identification accuracy was influenced by executive functioning, IQ and perhaps PSES, relationships not found with HC subjects. Phonological perception aided prosody identification in both diagnostic groups. As expected, both groups activated the STG while performing the prosody identification task. However, SPD subjects may have been less "efficient" in their recruitment of STG neurons. Finally, SPD subjects demonstrated a trend toward smaller STS volumes on the left, particularly the lower bank.

CONCLUSIONS

These data suggest that subtle differences between SPD and controls in phonological processing, executive functioning, IQ, and possibly PSES, contributed to difficulty in processing prosody for some SPD subjects.

Tracking executive function across the transition to school: a latent variable approach

This longitudinal study of executive function (EF) addressed three questions. These concerned: (i) the validity of EF as a latent construct underpinning performance at ages 4 and 6 on tests of planning, inhibitory control, and working memory; (ii) developmental change in EF across these time-points, which straddled children's transition to school; and (iii) verbal ability and family income as predictors of base-line individual differences and variation in the slopes of EF development. Confirmatory factor analyses of data from a socially diverse sample of 191 children supported the validity of a single EF construct at both time-points; a MIMIC (multiple indicators, multiple causes) model showed equally good fit for boys and girls. Latent growth models demonstrated that verbal mental age and family income predicted EF intercepts, but EF slopes were only related to verbal mental age. Across the transition to school, less able children (but not children from low income families) showed greater gains in EF than their peers.

The weirdest brains in the world

Henrich et al. provide a compelling argument about a bias in the behavioral sciences to study human behavior primarily in WEIRD populations. Here we argue that brain scientists are susceptible to similar biases, sampling primarily from WEIRD populations; and we discuss recent evidence from cultural neuroscience demonstrating the importance and viability of investigating culture across multiple levels of analysis.

Adolescent outcomes of childhood attention-deficit/hyperactivity disorder in a diverse community sample

OBJECTIVE

To describe adolescent outcomes of childhood attention-deficit/hyperactivity disorder (ADHD) in a diverse community sample.

METHOD

ADHD screening of a school district sample of 1,615 students aged 5 to 11 years was followed by a case-control study 8 years later. High-risk youths meeting full (n = 94) and subthreshold (n = 75) DSM-IV ADHD criteria were matched with demographically similar low-risk peers (n = 163). Outcomes domains included symptom, functional impairment, quality of life, substance use, educational outcomes, and juvenile justice involvement.

RESULTS

In all, 44% of youths with childhood ADHD had not experienced remission. Compared with unaffected peers, adolescents with childhood ADHD were more likely to display oppositional defiant disorder (odds ratio [OR] = 12.9, 95% confidence interval [CI] 5.6-30.0), anxiety/depression (OR = 10.3, 95% CI 2.7-39.3), significant functional impairment (OR = 3.4, 95% CI 1.7-6.9), reduced quality of life (OR = 2.5, 95% CI 1.3-4.7), and involvement with the juvenile justice system (OR = 3.1, 95% CI 1.0-9.1). Subthreshold ADHD, but not full ADHD, increased the risk of grade retention, whereas both conditions increased the risk of graduation failure. Oppositional defiant disorder (ODD), but not childhood ADHD, increased the risk of cannabis and alcohol use. None of the adolescent outcomes of childhood ADHD were moderated by gender, race or poverty.

CONCLUSIONS

ADHD heralds persistence of ADHD and comorbid symptoms into adolescence, as well as significant risks for functional impairment and juvenile justice involvement. Subthreshold ADHD symptoms typically do not qualify affected students for special educational interventions, yet increase the risk for adverse educational outcomes. Findings stress the importance of early ADHD recognition, especially its comorbid presentation with ODD, for prevention and intervention strategies.

Neurobiological pathways linking socioeconomic position and health

Across individuals, risk for poor health varies inversely with socioeconomic position (SEP). The pathways by which SEP affects health have been viewed from many epidemiological perspectives. Central to these perspectives is the notion that socioeconomic health disparities arise from an interplay between nested, recursive, and cumulative environmental, social, familial, psychological, behavioral, and physiological processes that unfold over the life span. Epidemiological perspectives on socioeconomic health disparities, however, have not yet formally integrated emerging findings from neuropharmacological, molecular genetic, and neuroimaging studies demonstrating that indicators of SEP relate to patterns of brain neurotransmission, brain morphology, and brain functionality implicated in the etiology of chronic medical conditions and psychological disorders. Here, we survey these emerging findings and consider how future neurobiological studies in this area can enhance our understanding of the pathways by which different dimensions of SEP become embodied by the brain to influence health throughout life.

Culturing the adolescent brain: what can neuroscience learn from anthropology?

Cultural neuroscience is set to flourish in the next few years. As the field develops, it is necessary to reflect on what is meant by 'culture' and how this can be translated for the laboratory context. This article uses the example of the adolescent brain to discuss three aspects of culture that may help us to shape and reframe questions, interpretations and applications in cultural neuroscience: cultural contingencies of categories, cultural differences in experience and cultural context of neuroscience research. The last few years have seen a sudden increase in the study of adolescence as a period of both structural and functional plasticity, with new brain-based explanations of teenage behaviour being taken up in education, policy and medicine. However, the concept of adolescence, as an object of behavioural science, took shape relatively recently, not much more than a hundred years ago and was shaped by a number of cultural and historical factors. Moreover, research in anthropology and cross-cultural psychology has shown that the experience of adolescence, as a period of the lifespan, is variable and contingent upon culture. The emerging field of cultural neuroscience has begun to tackle the question of cultural differences in social cognitive processing in adults. In this article, I explore what a cultural neuroscience can mean in the case of adolescence. I consider how to integrate perspectives from social neuroscience and anthropology to conceptualize, and to empirically study, adolescence as a culturally variable phenomenon, which, itself, has been culturally constructed.

Relationship of parental bonding styles with gray matter volume of dorsolateral prefrontal cortex in young adults

Previous epidemiologic studies using the parental bonding instrument (PBI), a self-report scale to rate attitudes of parents during the first 16 years, have suggested that a lower parental care score or higher parental overprotection score could lead to an increased risk of several psychiatric disorders, including schizophrenia and mood disorder. However, neuroimaging studies of an association between PBI scores and brain developmental abnormalities are still limited. In this region-of-interest analysis study using a cross-sectional design, we examined 50 normal young adults, in terms of relationships of parental bonding styles during the first 16 years measured by PBI with regional gray matter (GM) volume in the dorsolateral prefrontal cortex (DLPFC). Our study showed that paternal care score positively correlated with the GM volume in the left DLPFC, and paternal and maternal overprotection score negatively correlated with the GM volume in the left DLPFC. In conclusion, our results suggest that in normal young adults, lower paternal care and higher parental overprotection scores correlated with the GM volume reduction in the DLPFC.

The effects of early adversity on the adult and developing brain

PURPOSE OF REVIEW

Recent advances in neuroimaging methods have provided new ways of unravelling the complex interplay between genetic and environmental factors that influence functional brain development in the critical first years of life. This has allowed new insights into the effects that early adverse experience can exert on the brain later in life. We review recent progress in the characterization of those effects and underlying mechanisms through which adverse environment influences the neurocognitive development.

RECENT FINDINGS

Socioeconomic background may have a profound effect on structural and functional brain development, especially in the domains of language and prefrontal executive control. These effects are mediated by several factors: diet, quality of parental care, impoverished environment, prenatal exposure to toxic substances and so on. Other circumstances such as perinatal brain injury, early sensory deprivation or limb malformation may result in atypical functional organization of the brain and lasting cognitive impairment of certain functions. Early experience of maltreatment or institutionalized care may alter the development of the social brain, contributing to negative mental health outcomes, which may be partially reversed through early intervention programmes.

SUMMARY

Subsequent models of psychiatric disorder should take into account early risk factors and embrace developmental models at multiple levels of biological organization. There is a continuing need for the study of optimal environmental input during sensitive periods in brain development.

Language and brain volumes in children with epilepsy

In this study the relationship between language skill and frontotemporal volumes was compared in 69 medically treated subjects with epilepsy and 34 healthy children, aged 6.1-16.6 years. Also, whether patients with linguistic deficits had abnormal volumes and atypical associations between volumes and language skills in these brain regions was determined. The children underwent language testing and MRI scans at 1.5 T. Brain tissue was segmented and frontotemporal volumes were computed. Higher mean language scores were significantly associated with larger inferior frontal gyrus, temporal lobe, and posterior superior temporal gyrus gray matter volumes in the epilepsy group and in the children with epilepsy with average language scores. Increased total brain and dorsolateral prefrontal gray and white matter volumes, however, were associated with higher language scores in the healthy controls. Within the epilepsy group, linguistic deficits were related to smaller anterior superior temporal gyrus gray matter volumes and there was a negative association between language scores and dorsolateral prefrontal gray matter volumes. These findings demonstrate abnormal development of language-related brain regions, and imply differential reorganization of brain regions subserving language in children with epilepsy with normal linguistic skills and in those with impaired language.

Effects of socioeconomic status on brain development, and how cognitive neuroscience may contribute to levelling the playing field

The study of socioeconomic status (SES) and the brain finds itself in a circumstance unusual for Cognitive Neuroscience: large numbers of questions with both practical and scientific importance exist, but they are currently under-researched and ripe for investigation. This review aims to highlight these questions, to outline their potential significance, and to suggest routes by which they might be approached. Although remarkably few neural studies have been carried out so far, there exists a large literature of previous behavioural work. This behavioural research provides an invaluable guide for future neuroimaging work, but also poses an important challenge for it: how can we ensure that the neural data contributes predictive or diagnostic power over and above what can be derived from behaviour alone? We discuss some of the open mechanistic questions which Cognitive Neuroscience may have the power to illuminate, spanning areas including language, numerical cognition, stress, memory, and social influences on learning. These questions have obvious practical and societal significance, but they also bear directly on a set of longstanding questions in basic science: what are the environmental and neural factors which affect the acquisition and retention of declarative and nondeclarative skills? Perhaps the best opportunity for practical and theoretical interests to converge is in the study of interventions. Many interventions aimed at improving the cognitive development of low SES children are currently underway, but almost all are operating without either input from, or study by, the Cognitive Neuroscience community. Given that longitudinal intervention studies are very hard to set up, but can, with proper designs, be ideal tests of causal mechanisms, this area promises exciting opportunities for future research.

Non-linguistic auditory processing and working memory update in pre-school children who stutter: an electrophysiological study

Non-linguistic auditory processing and working memory update were examined with event-related potentials (ERPs) in 18 children who stutter (CWS) and 18 children who do not stutter (CWNS). Children heard frequent 1 kHz tones interspersed with rare 2 kHz tones. The two groups did not differ on any measure of the P1 and N1 components, strongly suggesting that early auditory processing of pure tones is unimpaired in CWS. However, as a group, only CWNS exhibited a P3 component to rare tones, suggesting that developmental stuttering may be associated with a less efficient attentional allocation and working memory update in response to auditory change.

Foundations for a new science of learning

Human learning is distinguished by the range and complexity of skills that can be learned and the degree of abstraction that can be achieved compared with those of other species. Homo sapiens is also the only species that has developed formal ways to enhance learning: teachers, schools, and curricula. Human infants have an intense interest in people and their behavior and possess powerful implicit learning mechanisms that are affected by social interaction. Neuroscientists are beginning to understand the brain mechanisms underlying learning and how shared brain systems for perception and action support social learning. Machine learning algorithms are being developed that allow robots and computers to learn autonomously. New insights from many different fields are converging to create a new science of learning that may transform educational practices.

Early parental care is important for hippocampal maturation: evidence from brain morphology in humans

The effects of early life experience on later brain structure and function have been studied extensively in animals, yet the relationship between childhood experience and normal brain development in humans remains largely unknown. Using a unique longitudinal data set including ecologically valid in-home measures of early experience during childhood (at age 4 and 8 years) and high-resolution structural brain imaging during adolescence (mean age 14 years), we examined the effects on later brain morphology of two dimensions of early experience: parental nurturance and environmental stimulation. Parental nurturance at age 4 predicts the volume of the left hippocampus in adolescence, with better nurturance associated with smaller hippocampal volume. In contrast, environmental stimulation did not correlate with hippocampal volume. Moreover, the association between hippocampal volume and parental nurturance disappears at age 8, supporting the existence of a sensitive developmental period for brain maturation. These findings indicate that variation in normal childhood experience is associated with differences in brain morphology, and hippocampal volume is specifically associated with early parental nurturance. Our results provide neuroimaging evidence supporting the important role of warm parental care during early childhood for brain maturation.

Cultural neuroscience and psychopathology: prospects for cultural psychiatry

There is a long tradition that seeks to understand the impact of culture on the causes, form, treatment, and outcome of psychiatric disorders. An early, colonialist literature attributed cultural characteristics and variations in psychopathology and behavior to deficiencies in the brains of colonized peoples. Contemporary research in social and cultural neuroscience holds the promise of moving beyond these invidious comparisons to a more sophisticated understanding of cultural variations in brain function relevant to psychiatry. To achieve this, however, we need better models of the nature of psychopathology and of culture itself. Culture is not simply a set of traits or characteristics shared by people with a common geographic, historical, or ethnic background. Current anthropology understands culture as fluid, flexible systems of discourse, institutions, and practices, which individuals actively use for self-fashioning and social positioning. Globalization introduces new cultural dynamics and demands that we rethink culture in relation to a wider domain of evolving identities, knowledge, and practice. Psychopathology is not reducible to brain dysfunction in either its causes, mechanisms, or expression. In addition to neuropsychiatric disorders, the problems that people bring to psychiatrists may result from disorders in cognition, the personal and social meanings of experience, and the dynamics of interpersonal interactions or social systems and institutions. The shifting meanings of culture and psychopathology have implications for efforts to apply cultural neuroscience to psychiatry. We consider how cultural neuroscience can refine use of culture and its role in psychopathology using the example of adolescent aggression as a symptom of conduct disorder.

Socioeconomic and cultural factors of low scholastic achievement of Roma children

This study investigated environmental influences on scholastic achievement of first-grade elementary school students. A total of 149 (average age 81 months) first-grade children were classified in three groups. The first group comprised of 52 Roma children. Two other groups consisted of 48 non-Roma children classified as children belonging to an average socioeconomic status (SES) group and 49 non-Roma children classified as children belonging to a below-average SES group. All 52 Roma children belonged to a below-average SES group. Children's intellectual abilities were assessed by Test of School Maturity; their scholastic achievement was assessed by teachers, while data on SES and family's educational climate were obtained through a semi structured interview with their parents. Intellectual abilities - strongly influenced by family's SES and family's educational climate - were most predictive of scholastic achievement. Our structural model suggests that family's educational climate, defined by unfavorable educational stimulation and low parents' ambition concerning education of their children, moderates effects of low SES on inferior scholastic achievement. This model may be especially relevant for Roma children, since Roma children are most affected by the lack of adequate educational climate within their families.