PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (100)
 

Clipboard (0)
None

Select a Filter Below

Journals
Year of Publication
1.  An Envisioned Bridge: Schooling as a Neurocognitive Developmental Institution 
The potential contribution of social science research to close the gap of knowledge between cognitive neuroscience and educational research has been underappreciated. Despite their virtual absence in the interdisciplinary dialog of neuroscience, sociology of education and related study of the cultural impact of formal education have generated research relevant to an understanding of how the social environment, such as widespread schooling, co-evolves with, and enhances neurocognitive development. Two clusters of isolated research literatures are synthesized that taken together anticipates a dynamic integration of neuroscience and education. The first cluster is on the social construction of cognition through formal education in contemporary society, including the effects of schooling on neurological and cognitive development; the demographic expansion of exposure to the developmental influence of schooling; and education’s cultural impact on the meaning of the learning experience and reinforcement of cognition as the key human capability across ever more key institutions in postindustrial society. The second cluster turns the issue around by examining current investigations from neuroscience that support neurological hypotheses about the causes behind the schooling effect on neurocognitive development. We propose that further integration of these literatures will provide a more ecologically valid context in which to investigate the evolving functional architecture of the contemporary brain.
doi:10.1016/j.dcn.2011.12.001
PMCID: PMC4507825  PMID: 22682912
2.  Neural Activation Associated with the Cognitive Emotion Regulation of Sadness in Healthy Children 
When used effectively, cognitive reappraisal of distressing events is a highly adaptive cognitive emotion regulation (CER) strategy, with impairments in cognitive reappraisal associated with greater risk for psychopathology. Despite extensive literature examining the neural correlates of cognitive reappraisal in healthy and psychiatrically ill adults, there is a dearth of data to inform the neural bases of CER in children, a key gap in the literature necessary to map the developmental trajectory of cognitive reappraisal. In this fMRI study, psychiatrically healthy schoolchildren were instructed to use cognitive reappraisal to modulate their emotional reactions and responses of negative affect after viewing sad photos. Consistent with the adult literature, when actively engaged in reappraisal compared to passively viewing sad photos, children showed increased activation in the vlPFC, dlPFC, and dmPFC as well as in parietal and temporal lobe regions. When children used cognitive reappraisal to minimize their experience of negative affect after viewing sad stimuli they exhibited dampened amygdala responses. Results are discussed in relation to the importance of identifying and characterizing neural processes underlying adaptive CER strategies in typically developing children in order to understand how these systems go awry and relate to the risk and occurrence of affective disorders.
doi:10.1016/j.dcn.2014.02.003
PMCID: PMC4061244  PMID: 24646887
Emotion; Emotion Regulation; Cognitive Reappraisal; fMRI; Sadness; Late Childhood
3.  Kids, Candy, Brain and Behavior: Age Differences in Responses to Candy Gains and Losses 
The development of reward-related neural systems, from adolescence through adulthood, has received much recent attention in the developmental neuroimaging literature. However, few studies have investigated behavioral and neural responses to both gains and losses in pre-pubertal child populations. To address this gap in the literature, in the present study healthy children aged 7–11 years and young-adults completed an fMRI card-guessing game using candy pieces delivered post-scan as an incentive. Age differences in behavioral and neural responses to candy gains/losses were investigated. Adults and children displayed similar responses to gains, but robust age differences were observed following candy losses within the caudate, thalamus, insula, and hippocampus. Interestingly, when task behavior was included as a factor in post-hoc mediation analyses, activation following loss within the caudate/thalamus related to task behavior and relationships with age were no longer significant. Conversely, relationships between response to loss and age within the hippocampus and insula remained significant even when controlling for behavior, with children showing heightened loss responses within the dorsal/posterior insula. These results suggest that both age and task behavior influence responses within the extended reward circuitry, and that children seem to be more sensitive than adults to loss feedback particularly within the dorsal/posterior insula.
doi:10.1016/j.dcn.2014.01.005
PMCID: PMC4061265  PMID: 24534632
reward; development; gain; loss; fMRI; child
4.  Brain Volume Reductions in Adolescent Heavy Drinkers 
Background
Brain abnormalities in adolescent heavy drinkers may result from alcohol exposure, or stem from pre-existing neural features.
Method
This longitudinal morphometric study investigated 40 healthy adolescents, ages 12–17 at study entry, half of whom (n=20) initiated heavy drinking over the 3 year follow-up. Both assessments included high-resolution magnetic resonance imaging. FreeSurfer was used to segment brain volumes, which were measured longitudinally using the newly developed QUARC tool.
Results
At baseline, participants who later transitioned into heavy drinking showed smaller left cingulate, pars triangularis, and rostral anterior cingulate volume, and less right cerebellar white matter volumes (p<.05), compared to continuous non-using teens. Over time, participants who initiated heavy drinking showed significantly greater volume reduction in the left ventral diencephalon, left inferior and middle temporal gyrus, and left caudate and brain stem, compared to substance-naïve youth (p<.05).
Conclusion
Findings suggest preexisting volume differences in frontal brain regions in future drinkers and greater brain volume reduction in subcortical and temporal regions after alcohol use was initiated. This is consistent with literature showing pre-existing cognitive deficits on tasks recruited by frontal regions, as well as post-drinking consequences on brain regions involved in language and spatial tasks.
doi:10.1016/j.dcn.2014.02.005
PMCID: PMC4061267  PMID: 24632141
adolescence; alcohol abuse; brain development; neuroimaging; magnetic resonance imaging
5.  Age-related Changes in Error Processing in Young Children: A School-based Investigation 
Growth in executive functioning skills (EF) play a role children’s academic success, and the transition to elementary school is an important time for the development of these abilities. Despite this, evidence concerning the development of the ERP components linked to EF, including the error-related negativity (ERN) and the error positivity (Pe), over this period is inconclusive. Data were recorded in a school setting from 3–7 year-old children (N=96, mean age=5 years 11 months) as they performed a Go/No-Go task. Results revealed the presence of the ERN and Pe on error relative to correct trials at all age levels. Older children showed increased response inhibition as evidenced by faster, more accurate responses. Although developmental changes in the ERN were not identified, the Pe increased with age. In addition, girls made fewer mistakes and showed elevated Pe amplitudes relative to boys. Based on a representative school-based sample, findings indicate that the ERN is present in children as young as 3, and that development can be seen in the Pe between ages 3–7. Results varied as a function of gender, providing insight into the range of factors associated with developmental changes in the complex relations between behavioral and electrophysiological measures of error processing.
doi:10.1016/j.dcn.2014.02.001
PMCID: PMC4061373  PMID: 24631799
error-related negativity; executive function; response inhibition; school-aged children; error positivity
6.  But do you think I’m cool? Developmental differences in striatal recruitment during direct and reflected social self-evaluations 
The current fMRI study investigated the neural foundations of evaluating oneself and others during early adolescence and young adulthood. Eighteen early adolescents (ages 11–14, M = 12.6) and 19 young adults (ages 22–31, M = 25.6) evaluated if academic, physical, and social traits described themselves directly (direct self-evaluations), described their best friend directly (direct other-evaluations), described themselves from their best friend’s perspective (reflected self-evaluations), or in general could change over time (control malleability-evaluations). Compared to control evaluations, both adolescents and adults recruited cortical midline structures during direct and reflected self-evaluations, as well as during direct other-evaluations, converging with previous research. However, unique to this study was a significant three-way interaction between age group, evaluative perspective, and domain within bilateral ventral striatum. Region of interest analyses demonstrated a significant evaluative perspective by domain interaction within the adolescent sample only. Adolescents recruited greatest bilateral ventral striatum during reflected social self-evaluations, which was positively correlated with age and pubertal development. These findings suggest that reflected social self-evaluations, made from the inferred perspective of a close peer, may be especially self-relevant, salient, or rewarding to adolescent self-processing – particularly during the progression through adolescence – and this feature persists into adulthood.
doi:10.1016/j.dcn.2014.01.003
PMCID: PMC4422645  PMID: 24582805
self; social cognition; adolescence; puberty; medial prefrontal cortex; ventral striatum
7.  The Potential of Infant fMRI Research and the Study of Early Life Stress as a Promising Exemplar 
Functional magnetic resonance imaging (fMRI) research with infants and toddlers has increased rapidly over the past decade, and provided a unique window into early brain development. In the current report, we review the state of the literature, which has established the feasibility and utility of task-based fMRI and resting state functional connectivity MRI (rs-fcMRI) during early periods of brain maturation. These methodologies have been successfully applied beginning in the neonatal period to increase understanding of how the brain both responds to environmental stimuli, and becomes organized into large-scale functional systems that support complex behaviors. We discuss the methodological challenges posed by this promising area of research. We also highlight that despite these challenges, early work indicates a strong potential for these methods to influence multiple research domains. As an example, we focus on the study of early life stress and its influence on brain development and mental health outcomes. We illustrate the promise of these methodologies for building on, and making important contributions to, the existing literature in this field.
doi:10.1016/j.dcn.2014.09.005
PMCID: PMC4385461  PMID: 25459874
infancy; natural sleep fMRI; resting state functional connectivity MRI; developmental neuroimaging; early life stress
8.  Equivalent neural responses in children and adolescents with and without Autism during judgments of affect 
doi:10.1016/j.dcn.2013.08.001
PMCID: PMC3931746  PMID: 24016745
emotion; autism; fmri; self-referential processing; connectivity
9.  Emotional reactivity and its impact on neural circuitry for attention-emotion interaction in childhood and adolescence 
Attention modulation when confronted with emotional stimuli is considered a critical aspect of executive function, yet rarely studied during childhood and adolescence, a developmental period marked with changes in these processes. We employed a novel, and child-friendly fMRI task that used emotional faces to investigate the neural underpinnings of the attention-emotion interaction in a child and adolescent sample (n=23, Age m=13.46, sd=2.86, range=8.05–16.93 years). Results implied modulation of activation in the orbitofrontal cortex (OFC) due to emotional distractor valence, which marginally correlated with participant age. Additionally, parent-reported emotional reactivity predicted the trajectory of BOLD signal increase for fearful emotional face distractors such that participants low in emotional reactivity had a steeper latency to peak activation. Results imply that the use of the OFC to modulate attention in the face of social/emotional stimuli may mature with age and may be tightly coupled with adaptive emotional functioning. Findings are discussed in the context of risk for the development of psychiatric disorders, where increased emotional reactivity is particularly apparent.
doi:10.1016/j.dcn.2013.08.005
PMCID: PMC3949237  PMID: 24055416
Emotion; Attention; Orbitofrontal Cortex; Emotional Reactivity; Development; Adolescence
10.  Neural circuitry of masked emotional face processing in youth with bipolar disorder, severe mood dysregulation, and healthy volunteers 
Youth with bipolar disorder (BD) and those with severe, non-episodic irritability (severe mood dysregulation, SMD) show face-emotion labeling deficits. These groups differ from healthy volunteers (HV) in neural responses to emotional faces. It is unknown whether awareness is required to elicit these differences. We compared activation in BD (N=20), SMD (N=18), and HV (N=22) during “Aware” and ”Non-aware” priming of shapes by emotional faces. Subjects rated how much they liked the shape. In Aware, a face (angry, fearful, happy, neutral, blank oval) appeared (187ms) before the shape. In Non-Aware, a face appeared (17ms), followed by a mask (170ms), and shape. A Diagnosis-by-Awareness-by-Emotion ANOVA was not significant. There were significant Diagnosis-by-Awareness interactions in occipital regions. BD and SMD showed increased activity for non-aware vs. aware; HV showed the reverse pattern. When subjects viewed angry or neutral faces, there were Emotion-by-Diagnosis interactions in face-emotion processing regions, including the L precentral gyrus, R posterior cingulate, R superior temporal gyrus, R middle occipital gyrus, and L medial frontal gyrus. Regardless of awareness, BD and SMD differ in activation patterns from HV and each other in multiple brain regions, suggesting that BD and SMD are distinct developmental mood disorders.
doi:10.1016/j.dcn.2013.09.007
PMCID: PMC3960306  PMID: 24239048
bipolar disorder; adolescence; mood disorder; functional neuroimaging; backwards masking; affective priming
11.  Reduced reward anticipation in youth at high-risk for unipolar depression: A preliminary study 
Offspring of depressed parents are at risk for depression and recent evidence suggests that reduced positive affect (PA) may be a marker of risk. We investigated whether self-reports of PA and fMRI-measured striatal response to reward, a neural correlate of PA, are reduced in adolescent youth at high familial risk for depression (HR) relative to youth at low familial risk for depression (LR). Functional magnetic resonance imaging assessments were conducted with 14 HR and 12 LR youth. All youth completed an ecological momentary assessment protocol to measure PA in natural settings and a self-report measure of depression symptomatology. Analyses found that HR youth demonstrated lower striatal response than LR youth during both reward anticipation and outcome. However, after controlling for youth self-reports of depression, HR youth demonstrated lower striatal response than LR youth only during reward anticipation. No significant differences were found between HR and LR youth on subjective ratings of PA or depressive symptoms. Results are consistent with previous findings that reduced reward response is a marker of risk for depression, particularly during reward anticipation, even in the absence of (or accounting for) disrupted subjective mood. Further examinations of prospective associations between reward response and depression onset are needed.
doi:10.1016/j.dcn.2013.11.005
PMCID: PMC3960320  PMID: 24369885
Depression; High-risk; Reward function; Positive affect; fMRI
12.  Loss aversion and 5HTT gene variants in adolescent anxiety 
Loss aversion, a well-documented behavioural phenomenon, characterizes decisions under risk in adult populations. As such, loss aversion may provide a reliable measure of risky behaviour. Surprisingly, little is known about loss aversion in adolescents, a group who manifests risk-taking behaviour, or in anxiety disorders, which is associated with risk-avoidance. Finally, loss aversion is expected to be modulated by genotype, particularly the serotonin transporter (SERT) gene variant, based on its role in anxiety and impulsivity. This genetic modulation may also differ between anxious and healthy adolescents, given their distinct propensities for risk taking. The present work examines the modulation of loss aversion, an index of risk-taking, and reaction-time to decision, an index of impulsivity, by the serotonin- transporter-gene-linked polymorphisms (5HTTLPR) in healthy and clinically anxious adolescents. Findings show that loss aversion (1) does manifest in adolescents, (2) does not differ between healthy and clinically anxious participants, and (3), when stratified by SERT genotype, identifies a subset of anxious adolescents who are high SERT-expressers, and show excessively low loss-aversion and high impulsivity. This last finding may serve as preliminary evidence for 5HTTLPR as a risk factor for the development of comorbid disorders associated with risk-taking and impulsivity in clinically anxious adolescents.
doi:10.1016/j.dcn.2013.10.002
PMCID: PMC3960326  PMID: 24280015
Risk-taking; microeconomics; lambda; impulsivity; development; risk-avoidance
13.  Girls’ Challenging Social Experiences in Early Adolescence Predict Neural Response to Rewards and Depressive Symptoms1 
Developmental models of psychopathology posit that exposure to social stressors may confer risk for depression in adolescent girls by disrupting neural reward circuitry. The current study tested this hypothesis by examining the relationship between early adolescent social stressors and later neural reward processing and depressive symptoms. Participants were 120 girls from an ongoing longitudinal study of precursors to depression across adolescent development. Low parental warmth, peer victimization, and depressive symptoms were assessed when the girls were 11 and 12 years old, and participants completed a monetary reward guessing fMRI task and assessment of depressive symptoms at age 16. Results indicate that low parental warmth was associated with increased response to potential rewards in the medial prefrontal cortex (mPFC), striatum, and amygdala, whereas peer victimization was associated with decreased response to potential rewards in the mPFC. Furthermore, concurrent depressive symptoms were associated with increased reward anticipation response in mPFC and striatal regions that were also associated with early adolescent psychosocial stressors, with mPFC and striatal response mediating the association between social stressors and depressive symptoms. These findings are consistent with developmental models that emphasize the adverse impact of early psychosocial stressors on neural reward processing and risk for depression in adolescence.
doi:10.1016/j.dcn.2013.12.003
PMCID: PMC3960334  PMID: 24397999
parental warmth; peer victimization; reward; fMRI; adolescence; depression
14.  Infants experience-dependent processing of male and female faces: Insights from eye tracking and event-related potentials 
The goal of the present study was to investigate infants’ processing of female and male faces. We used an event-related potential (ERP) priming task, as well as a visual-paired comparison (VPC) eye tracking task to explore how 7-month-old “female expert” infants differed in their responses to faces of different genders. Female faces elicited larger N290 amplitudes than male faces. Furthermore, infants showed a priming effect for female faces only, whereby the N290 was significantly more negative for novel females compared to primed female faces. The VPC experiment was designed to test whether infants could reliably discriminate between two female and two male faces. Analyses showed that infants were able to differentiate faces of both genders.
The results of the present study suggest that 7-month olds with a large amount of female face experience show a processing advantage for forming a neural representation of female faces, compared to male faces. However, the enhanced neural sensitivity to the repetition of female faces is not due to the infants' inability to discriminate male faces. Instead, the combination of results from the two tasks suggests that the differential processing for female faces may be a signature of expert-level processing.
doi:10.1016/j.dcn.2013.09.005
PMCID: PMC3960339  PMID: 24200421
Face Processing; Infants; Experience; Event-Related Potentials; Eye-Tracking
15.  Gaining Insight into Adolescent Vulnerability for Social Anxiety from Developmental Cognitive Neuroscience 
Social anxiety disorder (SAD) markedly impairs daily functioning. For adolescents, SAD can constrain typical development precisely when social experiences broaden, peers’ opinions are highly salient, and social approval is actively sought. Individuals with extreme, impairing social anxiety fear evaluation from others, avoid social interactions, and interpret ambiguous social cues as threatening. Yet some degree of social anxiety can be normative and non-impairing. Furthermore, a temperament of behavioral inhibition increases risk for SAD for some, but not all adolescents with this temperament. One fruitful approach taken to understand the mechanisms of social anxiety has been to use neuroimaging to link affect and cognition with neural networks implicated in the neurodevelopmental social reorientation of adolescence. Although initial neuroimaging studies of adolescent SAD and risk for SAD underscored the role of fear-processing circuits (e.g., the amygdala and ventral prefrontal cortex), recent work has expanded these circuits to include reward-processing structures in the basal ganglia. A growing focus on reward-related neural circuitry holds promise for innovative translational research needed to differentiate impairing from normative social anxiety and for novel ways to treat adolescent SAD that focus on both social avoidance and social approach.
doi:10.1016/j.dcn.2013.10.003
PMCID: PMC3960349  PMID: 24239049
social anxiety; behavioral inhibition; reward; threat; striatum; amygdala
16.  Neural measures of social attention across the first years of life: Characterizing typical development and markers of autism risk 
Few studies employing event-related potentials (ERPs) to examine infant perception/cognition have systematically characterized age-related changes over the first few years of life. Establishing a ‘normative’ template of development is important in its own right, and doing so may also better highlight points of divergence for high-risk populations of infants, such as those at elevated genetic risk for autism spectrum disorder (ASD). The present investigation explores the developmental progression of the P1, N290, P400 and Nc components for a large sample of young children between 6 and 36 months of age, addressing age-related changes in amplitude, sensitivity to familiar and unfamiliar stimuli and hemispheric lateralization. Two samples of infants are included: those at low- and high-risk for ASD. The four components of interest show differential patterns of change over time and hemispheric lateralization; however, infants at low- and high-risk for ASD do not show significant differences in patterns of neural response to faces. These results will provide a useful point of reference for future developmental cognitive neuroscience research targeting both typical development and vulnerable populations.
doi:10.1016/j.dcn.2013.09.006
PMCID: PMC3960357  PMID: 24183618
Autism; ASD; ERP; Event-related potentials; Infancy
17.  Exciting fear in adolescence: Does pubertal development alter threat processing? 
Adolescent development encompasses an ostensible paradox in threat processing. Risk taking increases dramatically after the onset of puberty, contributing to a 200% increase in mortality. Yet, pubertal maturation is associated with increased reactivity in threat-avoidance systems. In the first part of this paper we propose a heuristic model of adolescent affective development that may help to reconcile aspects of this paradox, which focuses on hypothesized pubertal increases in the capacity to experience (some) fear-evoking experiences as an exciting thrill. In the second part of this paper, we test key features of this model by examining brain activation to threat cues in a longitudinal study that disentangled pubertal and age effects. Pubertal increases in testosterone predicted increased activation to threat cues, not only in regions associated with threat avoidance (i.e., amygdala), but also regions associated with reward pursuit (i.e., nucleus accumbens). These findings are consistent with our hypothesis that puberty is associated with a maturational shift toward more complex processing of threat cues–which may contribute to adolescent tendencies to explore and enjoy some types of risky experiences.
doi:10.1016/j.dcn.2014.01.004
PMCID: PMC4227085  PMID: 24548554
Adolescence; Threat; Reward; Risk taking; Anxiety; Amygdala; Nucleus accumbens; Testosterone; Puberty
18.  By the sound of it. An ERP investigation of human action sound processing in 7-month-old infants 
Highlights
•Human action sounds are distinctly processed by 7-month-olds relative to other types of sounds.•7-month-olds differentiate living (human action, vocalizations) from non-living (environmental, mechanical) sounds.•Human vocalizations elicit increased posterior temporal and central LSW in 7-month-old infants.
Recent evidence suggests that human adults perceive human action sounds as a distinct category from human vocalizations, environmental, and mechanical sounds, activating different neural networks (Engel et al., 2009; Lewis et al., 2011). Yet, little is known about the development of such specialization. Using event-related potentials (ERP), this study investigated neural correlates of 7-month-olds’ processing of human action (HA) sounds in comparison to human vocalizations (HV), environmental (ENV), and mechanical (MEC) sounds. Relative to the other categories, HA sounds led to increased positive amplitudes between 470 and 570 ms post-stimulus onset at left anterior temporal locations, while HV led to increased negative amplitudes at the more posterior temporal locations in both hemispheres. Collectively, human produced sounds (HA + HV) led to significantly different response profiles compared to non-living sound sources (ENV + MEC) at parietal and frontal locations in both hemispheres. Overall, by 7 months of age human action sounds are being differentially processed in the brain, consistent with a dichotomy for processing living versus non-living things. This provides novel evidence regarding the typical categorical processing of socially relevant sounds.
doi:10.1016/j.dcn.2015.01.005
PMCID: PMC4381844  PMID: 25732377
Human sounds; Infancy; Human vocalizations; Cerebral specialization; Neurodevelopment; Categorical perception
19.  The neuropsychology of infants’ pro-social preferences 
Highlights
•Neural correlates of 6-month-old infants’ detection of pro-social agents.•ERP component P400 over posterior temporal areas index social valence.•First non-behavioral demonstration of pro-social preferences in young infants.
The current study is the first to investigate neural correlates of infants’ detection of pro- and antisocial agents. Differences in ERP component P400 over posterior temporal areas were found during 6-month-olds’ observation of helping and hindering agents (Experiment 1), but not during observation of identically moving agents that did not help or hinder (Experiment 2). The results demonstrate that the P400 component indexes activation of infants’ memories of previously perceived interactions between social agents. This leads to suggest that similar processes might be involved in infants’ processing of pro- and antisocial agents and other social perception processes (encoding gaze direction, goal directed grasping and pointing).
doi:10.1016/j.dcn.2015.01.006
PMCID: PMC4381845  PMID: 25681955
ERP; P400; Prosocial; Empathy; Infant; EEG
20.  Weak task-related modulation and stimulus representations during arithmetic problem solving in children with developmental dyscalculia 
Developmental cognitive neuroscience  2011;2(0 1):S152-S166.
Developmental dyscalculia (DD) is a disability that impacts math learning and skill acquisition in school-age children. Here we investigate arithmetic problem solving deficits in young children with DD using univariate and multivariate analysis of fMRI data. During fMRI scanning, 17 children with DD (ages 7–9, grades 2 and 3) and 17 IQ- and reading ability-matched typically developing (TD) children performed complex and simple addition problems which differed only in arithmetic complexity. While the TD group showed strong modulation of brain responses with increasing arithmetic complexity, children with DD failed to show such modulation. Children with DD showed significantly reduced activation compared to TD children in the intraparietal sulcus, superior parietal lobule, supramarginal gyrus and bilateral dorsolateral prefrontal cortex in relation to arithmetic complexity. Critically, multivariate representational similarity revealed that brain response patterns to complex and simple problems were less differentiated in the DD group in bilateral anterior IPS, independent of overall differences in signal level. Taken together, these results show that children with DD not only under-activate key brain regions implicated in mathematical cognition, but they also fail to generate distinct neural responses and representations for different arithmetic problems. Our findings provide novel insights into the neural basis of DD.
doi:10.1016/j.dcn.2011.09.006
PMCID: PMC4353634  PMID: 22682904
Developmental dyscalculia; Children; fMRI; Intraparietal sulcus; Arithmetic; Prefrontal cortex; Learning disabilities
21.  The effects of puberty on white matter development in boys 
Highlights
•White matter microstructural differences occurred between early and late puberty.•White matter regions showed reduced mean diffusivity from early to late puberty.•Regression models showed that pubertal effects could not simply be ascribed to age.•Mean diffusivity decreases were associated with increasing salivary testosterone levels.
Neuroimaging studies demonstrate considerable changes in white matter volume and microstructure during adolescence. Most studies have focused on age-related effects, whilst puberty-related changes are not well understood. Using diffusion tensor imaging and tract-based spatial statistics, we investigated the effects of pubertal status on white matter mean diffusivity (MD) and fractional anisotropy (FA) in 61 males aged 12.7–16.0 years. Participants were grouped into early-mid puberty (≤Tanner Stage 3 in pubic hair and gonadal development; n = 22) and late-post puberty (≥Tanner Stage 4 in pubic hair or gonadal development; n = 39). Salivary levels of pubertal hormones (testosterone, DHEA and oestradiol) were also measured. Pubertal stage was significantly related to MD in diverse white matter regions. No relationship was observed between pubertal status and FA. Regression modelling of MD in the significant regions demonstrated that an interaction model incorporating puberty, age and puberty × age best explained our findings. In addition, testosterone was correlated with MD in these pubertally significant regions. No relationship was observed between oestradiol or DHEA and MD. In conclusion, pubertal status was significantly related to MD, but not FA, and this relationship cannot be explained by changes in chronological age alone.
doi:10.1016/j.dcn.2014.10.002
PMCID: PMC4352899  PMID: 25454416
Adolescence; Brain development; Puberty; Structural magnetic resonance imaging; White matter; Diffusion tensor imaging; Testosterone
22.  Caudate responses to reward anticipation associated with delay discounting behavior in healthy youth 
Background
Choices requiring delay of gratification made during adolescence can have significant impact on life trajectory. Willingness to delay gratification can be measured using delay discounting tasks that require a choice between a smaller immediate reward and a larger delayed reward. Individual differences in the subjective value of delayed rewards are associated with risk for development of psychopathology including substance abuse. The neurobiological underpinnings related to these individual differences early in life are not fully understood. Using functional magnetic resonance imaging (fMRI), we tested the hypothesis that individual differences in delay discounting behavior in healthy youth are related to differences in responsiveness to potential reward.
Method
Nineteen 10 to 14 year-olds performed a monetary incentive delay task to assess neural sensitivity to potential reward and a questionnaire to measure discounting of future monetary rewards.
Results
Left ventromedial caudate activation during anticipation of potential reward was negatively correlated with delay discounting behavior. There were no regions where brain responses during notification of reward outcome were associated with discounting behavior.
Conclusions
Brain activation during anticipation of potential reward may serve as a marker for individual differences in ability or willingness to delay gratification in healthy youth.
doi:10.1016/j.dcn.2013.10.009
PMCID: PMC3932556  PMID: 24309299
adolescent; reward; fMRI; delay discounting; intertemporal choice; delayed gratification
23.  Electrophysiological measures of attention during speech perception predict metalinguistic skills in children 
Event-related potential (ERP) evidence demonstrates that preschool-aged children selectively attend to informative moments such as word onsets during speech perception. Although this observation indicates a role for attention in language processing, it is unclear whether this type of attention is part of basic speech perception mechanisms, higher-level language skills, or general cognitive abilities. The current study examined these possibilities by measuring ERPs from 5-year-old children listening to a narrative containing attention probes presented before, during, and after word onsets as well as at random control times. Children also completed behavioral tests assessing verbal and nonverbal skills. Probes presented after word onsets elicited a more negative ERP response beginning around 100 ms after probe onset than control probes, indicating increased attention to word-initial segments. Crucially, the magnitude of this difference was correlated with performance on verbal tasks, but showed no relationship to nonverbal measures. More specifically, ERP attention effects were most strongly correlated with performance on a complex metalinguistic task involving grammaticality judgments. These results demonstrate that effective allocation of attention during speech perception supports higher-level, controlled language processing in children by allowing them to focus on relevant information at individual word and complex sentence levels.
doi:10.1016/j.dcn.2013.10.005
PMCID: PMC3938020  PMID: 24316548
speech perception; selective attention; metalinguistic awareness; development; event-related potential
25.  Cognitive control network connectivity in adolescent women with and without a parental history of depression 
Background
Adolescent women with a parental history of depression are at high risk for the onset of major depressive disorder (MDD). Cognitive theories suggest this vulnerability involves deficits in cognitive control over emotional information. Among adolescent women with and without a parental history of depression, we examined differences in connectivity using resting state functional connectivity analysis within a network associated with cognitive control over emotional information.
Methods
Twenty-four depression-naïve adolescent women underwent resting state functional magnetic resonance imaging (fMRI). They were assigned to high-risk (n = 11) and low-risk (n = 13) groups based their parents’ depression history. Seed based functional connectivity analysis was used to examine group differences in connectivity within a network associated with cognitive control.
Results
High-risk adolescents had lower levels of connectivity between a right inferior prefrontal region and other critical nodes of the attention control network, including right middle frontal gyrus and right supramarginal gyrus. Further, greater severity of the parents’ worst episode of depression was associated with altered cognitive control network connectivity in their adolescent daughters.
Conclusions
Depressed parents may transmit depression vulnerability to their adolescent daughters via alterations in functional connectivity within neural circuits that underlie cognitive control of emotional information.
doi:10.1016/j.dcn.2013.10.008
PMCID: PMC4209722  PMID: 24270043
depression vulnerability; adolescence; parental history of depression; cognitive control network; resting-state fMRI; functional connectivity

Results 1-25 (100)