Impacts of early deprivation on behavioral and neural measures of executive function in early adolescence.

Children reared in institutional settings experience early deprivation that has lasting implications for multiple aspects of neurocognitive functioning, including executive function (EF). Changes in brain development are thought to contribute to these persistent EF challenges, but little research has used fMRI to investigate EF-related brain activity in children with a history of early deprivation. This study examined behavioral and neural data from a response conflict task in 12-14-year-olds who spent varying lengths of time in institutional care prior to adoption (N = 84; age at adoption - mean: 15.85 months, median: 12 months, range: 4-60 months). In initial analyses, earlier- and later-adopted (EA, LA) youth were compared to a group of children raised in their biological families (non-adopted, NA). NA youth performed significantly more accurately than LA youth, with EA youth falling in between. Imaging data suggested that previously institutionalized (PI) youth activated additional frontoparietal regions, including dorsolateral prefrontal cortex, as compared to NA youth. In addition, EA youth uniquely activated medial prefrontal regions, and LA uniquely activated parietal regions during this task. A separate analysis in a larger group of PI youth examined whether behavioral or brain measures of EF varied with the duration of deprivation experienced. Duration of deprivation was negatively associated with activation of default mode network (DMN) regions. Overall, results suggest that there are lasting effects of deprivation on EF, but that those who are removed from institutional care earlier may be able to recruit additional neural resources as a compensatory mechanism.

A Multilevel Examination of Cognitive Control in Adolescents With Nonsuicidal Self-injury.

Background: Nonsuicidal self-injury (NSSI), a transdiagnostic behavior, often emerges during adolescence. This study used the Research Domain Criteria approach to examine cognitive control (CC) with a focus on response inhibition and urgency relative to NSSI severity in adolescents. Methods: One hundred thirty-eight adolescents, assigned female sex at birth, with a continuum of NSSI severity completed negative and positive urgency measurements (self-report), an emotional Go/NoGo task within negative and positive contexts (behavioral), and structural and functional imaging during resting state and task (brain metrics). Cortical thickness, subcortical volume, resting-state functional connectivity, and task activation focused on an a priori-defined CC network. Eighty-four participants had all these main measures. Correlations and stepwise model selection followed by multiple regression were used to examine the association between NSSI severity and multiunit CC measurements. Results: Higher NSSI severity correlated with higher negative urgency and lower accuracy during positive no-inhibition (Go). Brain NSSI severity correlates varied across modalities and valence. For right medial prefrontal cortex and right caudate, higher NSSI severity correlated with greater negative but lower positive inhibition (NoGo) activation. The opposite pattern was observed for the right dorsolateral prefrontal cortex. Higher NSSI severity correlated with lower left dorsal anterior cingulate cortex (ACC) negative inhibition activation and thicker left dorsal ACC, yet it was correlated with higher right rostral ACC positive inhibition activation and thinner right rostral ACC, as well as lower CC network resting-state functional connectivity. Conclusions: Findings revealed multifaceted signatures of NSSI severity across CC units of analysis, confirming the relevance of this domain in adolescent NSSI and illustrating how multimodal approaches can shed light on psychopathology.

Testing the consequences of alcohol, cannabis, and nicotine use on hippocampal volume: a quasi-experimental cotwin control analysis of young adult twins.

BACKGROUND: Alcohol, cannabis, and nicotine use are highly comorbid and alarmingly prevalent in young adults. The hippocampus may be particularly sensitive to substance exposure. This remains largely untested in humans and familial risk may confound exposure effects. We extend prior work on alcohol and hippocampal volume in women by testing common and unique substance use effects and the potential moderating role of sex on hippocampal volume during emerging adulthood. A quasi-experimental cotwin control (CTC) design was used to separate familial risk from exposure consequences. METHODS: In a population-based sample of 435 24-year-old same-sex twins (58% women), dimensional measures (e.g. frequency, amount) of alcohol, cannabis, and nicotine use across emerging adulthood were assessed. Hippocampal volume was assessed using MRI. RESULTS: Greater substance use was significantly associated with lower hippocampal volume for women but not men. The same pattern was observed for alcohol, cannabis, and nicotine. CTC analyses provided evidence that hippocampal effects likely reflected familial risk and the consequence of substance use in general and alcohol and nicotine in particular; cannabis effects were in the expected direction but not significant. Within-pair mediation analyses suggested that the effect of alcohol use on the hippocampus may reflect, in part, comorbid nicotine use. CONCLUSIONS: The observed hippocampal volume deviations in women likely reflected substance-related premorbid familial risk and the consequences of smoking and, to a lesser degree, drinking. Findings contribute to a growing body of work suggesting heightened risk among women toward experiencing deleterious effects of substance exposure on the still-developing young adult hippocampus.

Reduced Hippocampal Volumes in Children with History of Hypoxic Ischemic Encephalopathy after Therapeutic Hypothermia.

Hypoxic ischemic encephalopathy (HIE) remains a significant cause of disability despite treatment with therapeutic hypothermia (TH). Many survive with more subtle deficits that affect daily functioning and school performance. We have previously shown an early indication of hippocampal changes in infants with HIE despite TH. The aim of this study was to evaluate the hippocampal volume via MRI and memory function at 5 years of age. A cohort of children followed from birth returned for a 5-year follow-up (n = 10 HIE treated with TH, n = 8 healthy controls). The children underwent brain MRI and neurodevelopmental testing to assess their brain volume, general development, and memory function. Children with HIE had smaller hippocampal volumes than the controls despite no differences in the total brain volume (p = 0.02). Children with HIE generally scored within the average range on developmental testing. Though there was no difference in the memory scores between these groups, there was a positive within-group correlation between the hippocampal volume and memory scores in children with HIE (sentence recall r = 0.66, p = 0.038). There was no relationship between newborn memory function and 5-year hippocampal size. Children with HIE treated with TH experienced significant and lasting changes to the hippocampus despite improvements in survival and severe disability. Future studies should target diminishing injury to the hippocampus to improve overall outcomes.

Age-related differences in resting-state functional connectivity from childhood to adolescence.

The human brain is active at rest, and spontaneous fluctuations in functional MRI BOLD signals reveal an intrinsic functional architecture. During childhood and adolescence, functional networks undergo varying patterns of maturation, and measures of functional connectivity within and between networks differ as a function of age. However, many aspects of these developmental patterns (e.g. trajectory shape and directionality) remain unresolved. In the present study, we characterised age-related differences in within- and between-network resting-state functional connectivity (rsFC) and integration (i.e. participation coefficient, PC) in a large cross-sectional sample of children and adolescents (n = 628) aged 8-21 years from the Lifespan Human Connectome Project in Development. We found evidence for both linear and non-linear differences in cortical, subcortical, and cerebellar rsFC, as well as integration, that varied by age. Additionally, we found that sex moderated the relationship between age and putamen integration where males displayed significant age-related increases in putamen PC compared with females. Taken together, these results provide evidence for complex, non-linear differences in some brain systems during development.

Developmental trajectories of cortical thickness by functional brain network: The roles of pubertal timing and socioeconomic status.

The human cerebral cortex undergoes considerable changes during development, with cortical maturation patterns reflecting regional heterogeneity that generally progresses in a posterior-to-anterior fashion. However, the organizing principles that govern cortical development remain unclear. In the current study, we characterized age-related differences in cortical thickness (CT) as a function of sex, pubertal timing, and two dissociable indices of socioeconomic status (i.e., income-to-needs and maternal education) in the context of functional brain network organization, using a cross-sectional sample (n = 789) diverse in race, ethnicity, and socioeconomic status from the Lifespan Human Connectome Project in Development (HCP-D). We found that CT generally followed a linear decline from 5 to 21 years of age, except for three functional networks that displayed nonlinear trajectories. We found no main effect of sex or age by sex interaction for any network. Earlier pubertal timing was associated with reduced mean CT and CT in seven networks. We also found a significant age by maternal education interaction for mean CT across cortex and CT in the dorsal attention network, where higher levels of maternal education were associated with steeper age-related decreases in CT. Taken together, our results suggest that these biological and environmental variations may impact the emerging functional connectome.

Graded Variation in T1w/T2w Ratio during Adolescence: Measurement, Caveats, and Implications for Development of Cortical Myelin.

Adolescence is characterized by the maturation of cortical microstructure and connectivity supporting complex cognition and behavior. Axonal myelination influences brain connectivity during development by enhancing neural signaling speed and inhibiting plasticity. However, the maturational timing of cortical myelination during human adolescence remains poorly understood. Here, we take advantage of recent advances in high-resolution cortical T1w/T2w mapping methods, including principled correction of B1+ transmit field effects, using data from the Human Connectome Project in Development (HCP-D; N = 628, ages 8-21). We characterize microstructural changes relevant to myelination by estimating age-related differences in T1w/T2w throughout the cerebral neocortex from childhood to early adulthood. We apply Bayesian spline models and clustering analysis to demonstrate graded variation in age-dependent cortical T1w/T2w differences that are correlated with the sensorimotor-association (S-A) axis of cortical organization reported by others. In sensorimotor areas, T1w/T2w ratio measures start at high levels at early ages, increase at a fast pace, and decelerate at later ages (18-21). In intermediate multimodal areas along the S-A axis, T1w/T2w starts at intermediate levels and increases linearly at an intermediate pace. In transmodal/paralimbic association areas, T1w/T2w starts at low levels and increases linearly at the slowest pace. These data provide evidence for graded variation of the T1w/T2w ratio along the S-A axis that may reflect cortical myelination changes during adolescence underlying the development of complex information processing and psychological functioning. We discuss the implications of these results as well as caveats in interpreting magnetic resonance imaging (MRI)-based estimates of myelination.SIGNIFICANCE STATEMENT Myelin is a lipid membrane that is essential to healthy brain function. Myelin wraps axons to increase neural signaling speed, enabling complex neuronal functioning underlying learning and cognition. Here, we characterize the developmental timing of myelination across the cerebral cortex during adolescence using a noninvasive proxy measure, T1w/T2w mapping. Our results provide new evidence demonstrating graded variation across the cortex in the timing of T1w/T2w changes during adolescence, with rapid T1w/T2w increases in lower-order sensory areas and gradual T1w/T2w increases in higher-order association areas. This spatial pattern of microstructural brain development closely parallels the sensorimotor-to-association axis of cortical organization and plasticity during ontogeny.

Impact of childhood maltreatment and resilience on behavioral and neural patterns of inhibitory control during emotional distraction.

Exposure to childhood maltreatment (CM) may disrupt typical development of neural systems underlying impulse control and emotion regulation. Yet resilient outcomes are observed in some individuals exposed to CM. Individual differences in adult functioning may result from variation in inhibitory control in the context of emotional distractions, underpinned by cognitive-affective brain circuits. Thirty-eight healthy adults with a history of substantiated CM and 34 nonmaltreated adults from the same longitudinal sample performed a Go/No-Go task in which task-relevant stimuli (letters) were presented at the center of task-irrelevant, negative, or neutral images, while undergoing functional magnetic resonance imaging. The comparison group, but not the maltreated group, made increased inhibitory control errors in the context of negative, but not neutral, distractor images. In addition, the comparison group had greater right inferior frontal gyrus and bilateral frontal pole activation during inhibitory control blocks with negative compared to neutral background images relative to the CM group. Across the full sample, greater adaptive functioning in everyday contexts was associated with superior inhibitory control and greater right frontal pole activation. Results suggest that resilience following early adversity is associated with enhanced attention and behavioral regulation in the context of task-irrelevant negative emotional stimuli in a laboratory setting.

Measurement matters: An individual differences examination of family socioeconomic factors, latent dimensions of children's experiences, and resting state functional brain connectivity in the ABCD sample.

The variation in experiences between high and low-socioeconomic status contexts are posited to play a crucial role in shaping the developing brain and may explain differences in child outcomes. Yet, examinations of SES and brain development have largely been limited to distal proxies of these experiences (e.g., income comparisons). The current study sought to disentangle the effects of multiple socioeconomic indices and dimensions of more proximal experiences on resting-state functional connectivity (rsFC) in a sample of 7834 youth (aged 9-10 years) from the Adolescent Brain Cognitive Development (ABCD) study. We applied moderated nonlinear factor analysis (MNLFA) to establish measurement invariance among three latent environmental dimensions of experience (material/economic deprivation, caregiver social support, and psychosocial threat). Results revealed measurement biases as a function of child age, sex, racial group, family income, and parental education, which were statistically adjusted in the final MNLFA scores. Mixed-effects models demonstrated that socioeconomic indices and psychosocial threat differentially predicted variation in frontolimbic networks, and threat statistically moderated the association between income and connectivity between the dorsal and ventral attention networks. Findings illuminate the importance of reducing measurement biases to gain a more socioculturally-valid understanding of the complex and nuanced links between socioeconomic context, children's experiences, and neurodevelopment.

The Effects of Alcohol and Cannabis Use on the Cortical Thickness of Cognitive Control and Salience Brain Networks in Emerging Adulthood: A Co-twin Control Study.

BACKGROUND: Impairments in inhibitory control and its underlying brain networks (control/salience areas) are associated with substance misuse. Research often assumes a causal substance exposure effect on brain structure. This assumption remains largely untested, and other factors (e.g., familial risk) may confound exposure effects. We leveraged a genetically informative sample of twins aged 24 years and a quasi-experimental co-twin control design to separate alcohol or cannabis exposure effects during emerging adulthood from familial risk on control/salience network cortical thickness. METHODS: In a population-based sample of 436 twins aged 24 years, dimensional measures of alcohol and cannabis use (e.g., frequency, density, quantity, intoxications) across emerging adulthood were assessed. Cortical thickness of control/salience network areas were assessed using magnetic resonance imaging and defined by a fine-grained cortical atlas. RESULTS: Greater alcohol, but not cannabis, misuse was associated with reduced thickness of prefrontal (e.g., dorso/ventrolateral, right frontal operculum) and frontal medial cortices, as well as temporal lobe, intraparietal sulcus, insula, parietal operculum, precuneus, and parietal medial areas. Effects were predominately (pre)frontal and right lateralized. Co-twin control analyses suggested that the effects likely reflect both the familial predisposition to misuse alcohol and, specifically for lateral prefrontal, frontal/parietal medial, and right frontal operculum, an alcohol exposure effect. CONCLUSIONS: This study provides novel evidence that alcohol-related reductions in cortical thickness of control/salience brain networks likely represent the effects of alcohol exposure and premorbid characteristics of the genetic predisposition to misuse alcohol. The dual effects of these two alcohol-related causal influences have important and complementary implications regarding public health and prevention efforts to curb youth drinking.

Orbitofrontal cortex thickness and substance use disorders in emerging adulthood: causal inferences from a co-twin control/discordant twin study.

BACKGROUND/AIMS: Research linking orbitofrontal cortex (OFC) structure and substance use disorders (SUDs) is largely correlational and often implies a causal effect of addiction/substance exposure on the brain, but familial risk factors (e.g. genetic liability) may confound these associations. We tested whether associations between alcohol, cannabis and tobacco use disorders and OFC thickness reflected the potential causal effects of familial risk or SUDs-related consequences (e.g. substance exposure). DESIGN: A co-twin control/discordant twin design separated familial risk confounding from SUD-related consequences. SETTING/PARTICIPANTS: A population-based sample of 436 24-year-old twins (62% monozygotic) from the Minnesota Twin Family Study, USA. MEASUREMENTS: Alcohol, cannabis and tobacco use disorders were assessed using the Composite International Diagnostic Interview-Substance Abuse Module. Cortical thickness of the medial and lateral OFC (mOFC and lOFC, respectively) was assessed using magnetic resonance imaging (MRI). FINDINGS: Lower mOFC (P-values ≤ 0.006) but not lOFC (P-values ≥ 0.190) thickness was observed in diagnosed individuals (n = 185) relative to non-SUD controls (n = 251). Co-twin control analyses offered evidence that mOFC associations were consistent with familial risk across SUDs (between-pair effect: P-values ≤ 0.047) and the independent consequences of having an alcohol or cannabis use disorder (within-pair effect: P-values ≤ 0.024). That is, within alcohol/cannabis discordant twin pairs, affected twins had significantly lower mOFC thickness compared with their unaffected co-twins. CONCLUSIONS: A confounder-adjusted analysis of the Minnesota Twin Family Study appeared to indicate that, beyond a substance use disorders general familial risk effect, the experience of an alcohol or cannabis use disorder in emerging adulthood reduces the thickness of the medial orbitofrontal cortex, a region associated with value-guided decision-making.

Accelerated maturation in functional connectivity following early life stress: Circuit specific or broadly distributed?

Psychosocial acceleration theory and other frameworks adapted from life history predict a link between early life stress and accelerated maturation in several physiological systems. Those findings led researchers to suggest that the emotion-regulatory brain circuits of previously-institutionalized (PI) youth are more mature than youth raised in their biological families (non-adopted, or NA, youth) during emotion tasks. Whether this accelerated maturation is evident during resting-state fMRI has not yet been established. Resting-state fMRI data from 83 early adolescents (Mage = 12.9 years, SD = 0.57 years) including 41 PI and 42 NA youth, were used to examine seed-based functional connectivity between the amygdala and ventromedial prefrontal cortex (vmPFC). Additional whole-brain analyses assessed group differences in functional connectivity and associations with cognitive performance and behavior. We found group differences in amygdala - vmPFC connectivity that may be consistent with accelerated maturation following early life stress. Further, whole-brain connectivity analyses revealed group differences associated with internalizing and externalizing symptoms. However, the majority of whole-brain results were not consistent with an accelerated maturation framework. Our results suggest early life stress in the form of institutional care is associated with circuit-specific alterations to a frontolimbic emotion-regulatory system, while revealing limited differences in more broadly distributed networks.

Validation of an online version of the Trier Social Stress Test in a study of adolescents.

INTRODUCTION: The Trier Social Stress Test (TSST) is the most widely used protocol for activating a stress response of the hypothalamic-pituitary-adrenocortical (HPA) axis and other stress-mediating systems. A number of variants of the TSST exist, including ones for children, groups, and virtual reality. All of these versions, though, require in-person assessment. The COVID-19 pandemic has made in-person assessment impossible or extremely difficult and potentially dangerous. The purpose of this study was to validate a completely remote, online, version of the TSST for children. METHOD: A sample of 68 (27 female) 15- and 16-year old participants were administered the TSST-Online (TSST-OL) during the late afternoon hours (3-6 p.m. start time). The participants, judges (one male, one female), and experimenter (female) all joined the assessment from their own homes via the online platform, ZOOM™. Two sessions were conducted, one to obtain consent, explain procedures, work with the family to arrange the computer and room set-up for the TSST-OL and one within two weeks to conduct the procedure. The participants were trained to take their own saliva samples and a saliva sampling kit was mailed to the home in between the first and second session. The samples were then mailed to the researchers within a day of collection. The participant was observed during saliva collection to determine correct procedures were followed. Salivary cortisol, salivary α-amylase and self-reports of stress were measured multiple times over the second session. RESULTS: rmANOVAs yielded a significant effect of trials, for cortisol, F(1.37,90.46) = 15.13, p = .001, sAA, F(2.75,146.68) = 6.91, p = .001, and self-rated stress, F(3.43,222.69) = 118.73, p = .001. There were no significant sex by trials interactions for any measure, although females reported more stress than males, F(1,65) = 9.14, p = .004. For cortisol, from baseline to expected peak (30 min after the onset of speech preparation), the Cohen's effect size was dz = 0.57. Using 1.5 nmol/l (or 0.54 µg/dl) as the criterion for a response (Miller, Plessow, Kirschaum, & Stalder, 2013), 63% of the participants produced a significant increase in cortisol. CONCLUSIONS: The responses to the TSST-OL are consistent with in-person responses among children and adolescents (see recent meta-analysis (Seddon et al., 2020). The protocol is a viable way of assessing reactivity of the HPA axis and other stress systems without needing to bring the participant into the research laboratory. This method will be useful during periods of widespread infection. It should also work to study populations who all live too far from the research laboratory to be assessed in person.

Differential brain activity as a function of social evaluative stress in early adolescence: Brain function and salivary cortisol.

Understanding individual differences in neural responses to stressful environments is an important avenue of research throughout development. These differences may be especially critical during adolescence, which is characterized by opportunities for healthy development and increased susceptibility to the development of psychopathology. While the neural correlates of the psychosocial stress response have been investigated in adults, these links have not been explored during development. Using a new task, the Minnesota Imaging Stress Test in Children (MISTiC), differences in activation are found in fusiform gyrus, superior frontal gyrus, insula, and anterior cingulate cortex when comparing a stressful math task to a nonstressful math task. The MISTiC task successfully elicits cortisol responses in a similar proportion of adolescents as in behavioral studies while collecting brain imaging data. Cortisol responders and nonresponders did not differ in their perceived stress level or behavioral performance during the task despite differences in neuroendocrine function. Future research will be able to leverage the MISTiC task for many purposes, including probing associations between individual differences in stress responses with environmental conditions, personality differences, and the development of psychopathology.

Trait neuroticism and emotion neurocircuitry: Functional magnetic resonance imaging evidence for a failure in emotion regulation.

Though theory suggests that individual differences in neuroticism (a tendency to experience negative emotions) would be associated with altered functioning of the amygdala (which has been linked with emotionality and emotion dysregulation in childhood, adolescence, and adulthood), results of functional neuroimaging studies have been contradictory and inconclusive. We aimed to clarify the relationship between neuroticism and three hypothesized neural markers derived from functional magnetic resonance imaging during negative emotion face processing: amygdala activation, amygdala habituation, and amygdala-prefrontal connectivity, each of which plays an important role in the experience and regulation of emotions. We used general linear models to examine the relationship between trait neuroticism and the hypothesized neural markers in a large sample of over 500 young adults. Although neuroticism was not significantly associated with magnitude of amygdala activation or amygdala habituation, it was associated with amygdala-ventromedial prefrontal cortex connectivity, which has been implicated in emotion regulation. Results suggest that trait neuroticism may represent a failure in top-down control and regulation of emotional reactions, rather than overactive emotion generation processes, per se. These findings suggest that neuroticism, which has been associated with increased rates of transdiagnostic psychopathology, may represent a failure in the inhibitory neurocircuitry associated with emotion regulation.

Childhood Maltreatment Disrupts Brain-Mediated Pathways Between Adolescent Maternal Relationship Quality and Positive Adult Outcomes.

The quality of early caregiving may partially shape brain structure and circuits involved in regulating emotions, including the frontal cortex, affecting vulnerability to the development of psychopathology and maladaptation. Given the profound impact of child maltreatment (CM) on psychological and neural development, we tested whether CM alters the pathways linking mother-adolescent relationship, frontal cortex, and adult outcomes. We used structural equation modeling to investigate whether CM history affected the association between mother-child relationship quality during early adolescence, frontal lobe volume in adulthood, and adult internalizing and externalizing symptomatology and competence. Participants from a longitudinal high-risk, low-income sample included 48 adults with a history of CM and 40 adults without such history (M = 30.0 years). Results showed that greater frontal lobe volume predicted higher levels of adult adaptive functioning and fewer adult internalizing symptoms but showed no relation to adult externalizing symptoms. Frontal lobe volume significantly mediated the effect of adolescent maternal relationship quality on both adult internalizing symptoms and adult adaptive functioning, but only for individuals with no maltreatment history. Given the observed relationship between frontal lobe volume and healthy adult functioning across the full sample, it will be important to identify protective factors in maltreated individuals that foster frontal lobe development.

Alexithymia is associated with neural reactivity to masked emotional faces in adolescents who self-harm.

BACKGROUND: Non-suicidal self-injury (NSSI) is a major, trans-diagnostic mental health problem among adolescents. Alexithymia has been identified as a developmental risk factor for NSSI. Research on how alexithymia relates to the neurobiology of automatic emotion processing is only beginning to emerge. This study evaluates the relationship between alexithymic features and neural responses to automatic processing of emotional content in adolescents with NSSI. METHODS: 25 female adolescents (ages 13-21) with a history of repeated engagement in NSSI completed the Toronto Alexithymia Scale and the Difficulties with Emotion Regulation Scale and underwent functional magnetic resonance imaging (fMRI) during a task in which participants were exposed to masked emotions. RESULTS: One facet of alexithymia, limited internal emotion awareness or externally-oriented thinking (EOT), was related to differential reactivity to masked emotional faces in clusters in the right supramarginal gyrus and right inferior frontal gyrus. Follow-up assessment of regional reactivity revealed that greater EOT is associated with lower activation to masked happy faces but higher activation to masked fearful faces. Other facets of alexithymia did not show relationships with reactivity to masked emotional faces. LIMITATIONS: This is a cross-sectional and small sample that only includes females, which may attenuate generalizability of findings. CONCLUSIONS: We report neural correlates of multiple facets of alexithymia in adolescents with NSSI. Among adolescents who self-harm, those with higher levels of EOT may be less alert to subtle positively-valenced emotion cues. For this subset of adolescents with NSSI, interventions designed to enhance mental representation of emotional responses and attention to positive emotions may be appropriate.

Individual differences in ERP measures of executive function in early childhood: Relation to low-risk preterm birth and parent-reported behavior.

Although behavioral studies have demonstrated that executive function (EF) develops rapidly during early childhood, few studies have investigated neural systems supporting EF during the preschool years. These systems are sensitive to variations in children's early life experiences, including preterm birth. The current study collected behavioral and event related potential (ERP) data during an EF task (directional Stroop) in a sample of 150 full-term and low-risk preterm children aged 4-years. Children's IQ and processing speed (WPPSI-III), and parent report of EF (BRIEF-P), were also measured. Forty-nine children born full-term and 43 low-risk preterm children provided useable ERP data. Similar to prior studies with adults and older children, preschool-aged children showed modulation of ERP components (N2, P3) by cognitive conflict. Effects of trial type were also present for early attentional components (N1 and P2). Exploratory analyses demonstrated that ERP measures of EF were correlated with individual differences in cognitive and behavioral functioning in both full-term and low-risk preterm populations. Future research investigating the neural correlates of early measures of EF in low-risk preterm children and other at-risk groups is warranted to better understand how trajectories of EF development are altered in the first years of life.

Extending the Human Connectome Project across ages: Imaging protocols for the Lifespan Development and Aging projects.

The Human Connectome Projects in Development (HCP-D) and Aging (HCP-A) are two large-scale brain imaging studies that will extend the recently completed HCP Young-Adult (HCP-YA) project to nearly the full lifespan, collecting structural, resting-state fMRI, task-fMRI, diffusion, and perfusion MRI in participants from 5 to 100+ years of age. HCP-D is enrolling 1300+ healthy children, adolescents, and young adults (ages 5-21), and HCP-A is enrolling 1200+ healthy adults (ages 36-100+), with each study collecting longitudinal data in a subset of individuals at particular age ranges. The imaging protocols of the HCP-D and HCP-A studies are very similar, differing primarily in the selection of different task-fMRI paradigms. We strove to harmonize the imaging protocol to the greatest extent feasible with the completed HCP-YA (1200+ participants, aged 22-35), but some imaging-related changes were motivated or necessitated by hardware changes, the need to reduce the total amount of scanning per participant, and/or the additional challenges of working with young and elderly populations. Here, we provide an overview of the common HCP-D/A imaging protocol including data and rationales for protocol decisions and changes relative to HCP-YA. The result will be a large, rich, multi-modal, and freely available set of consistently acquired data for use by the scientific community to investigate and define normative developmental and aging related changes in the healthy human brain.

Risk taking, decision-making, and brain volume in youth adopted internationally from institutional care.

Early life stress in the form of early institutional care has been shown to have wide-ranging impacts on the biological and behavioral development of young children. Studies of brain structure using magnetic resonance imaging have reported decreased prefrontal volumes, and a large literature has detailed decreased executive function (EF) in post-institutionalized (PI) youth. Little is known about how these findings relate to decision-making, particularly in PI youth entering adolescence-a period often characterized by social transition and increased reliance upon EF skills and the still-maturing prefrontal regions that support them. As decision-making in risky situations can be an especially important milestone in early adolescence, a clearer knowledge of the relationship between risky decision making and prefrontal structures in post-institutionalized youth is needed. The youth version of the Balloon Analogue Risk Task and a two-deck variant of the Iowa Gambling Task were used to assess risky decision-making in post-institutionalized youth and a community control group (N = 74, PI = 44, Non-adopted = 30; mean age = 12.93). Participants also completed a structural MRI scan for the assessment of group differences in brain structure. We hypothesized that participants adopted from institutions would display poorer performance on risky-decision making tasks and smaller brain volumes compared to non-adopted youth. Results indicated that later-adopted participants made fewer risky decisions than those experiencing shorter periods of deprivation or no institutional rearing. Further, decreased prefrontal volumes were observed in later-adopted youth and were significantly associated with task performance. Our results suggest that changes in risky-decision making behavior and brain structure are associated with the duration of early institutional care.