Neural origin of cognitive shifting in young children

Preventive effect of one-session brief focused attention meditation on state fatigue: Resting state functional magnetic resonance imaging study

INTRODUCTION

The extended practice of meditation may reduce the influence of state fatigue by changing neurocognitive processing. However, little is known about the preventive effects of one-session brief focused attention meditation (FAM) on state fatigue in healthy participants or its potential neural mechanisms. This study examined the preventive effects of one-session brief FAM on state fatigue and its neural correlates using resting-state functional MRI (rsfMRI) measurements.

METHODS

We randomly divided 56 meditation-naïve participants into FAM and control groups. After the first rsfMRI scan, each group performed a 10-minute each condition while wearing a functional near-infrared spectroscopy (fNIRS) device for assessing brain activity. Subsequently, following a second rsfMRI scan, the participants completed a fatigue-inducing task (a Go/NoGo task) for 60 min. We evaluated the temporal changes in the Go/NoGo task performance of participants as an indicator of state fatigue. We then calculated changes in the resting-state functional connectivity (rsFC) of the rsfMRI from before to after each condition and compared them between groups. We also evaluated neural correlates between the changes in rsFC and state fatigue.

RESULTS AND DISCUSSION

The fNIRS measurements indicated differences in brain activity during each condition between the FAM and control groups, showing decreased medial prefrontal cortex activity and decreased functional connectivity between the medial prefrontal cortex and middle frontal gyrus. The control group exhibited a decrement in Go/NoGo task performance over time, whereas the FAM group did not. These results, thus, suggested that FAM could prevent state fatigue. Compared with the control group, the rsFC analysis revealed a significant increase in the connectivity between the left dorsomedial prefrontal cortex and right superior parietal lobule in the FAM group, suggesting a modification of attention regulation by cognitive effort. In the control group, increased connectivity was observed between the bilateral posterior cingulate cortex and left inferior occipital gyrus, which might be associated with poor attention regulation and reduced higher-order cognitive function. Additionally, the change in the rsFC of the control group was related to state fatigue.

CONCLUSION

Our findings suggested that one session of 10-minute FAM could prevent behavioral state fatigue by employing cognitive effort to modify attention regulation as well as suppressing poor attention regulation and reduced higher-order cognitive function.

Inhibitory Control, Cognitive Flexibility, and the Production of Disfluencies in Children Who Do and Do Not Stutter

PURPOSE

Differences in inhibitory control and cognitive flexibility between children who stutter (CWS) and children who do not stutter (CWNS) have been previously demonstrated. The aim of the current study was to investigate whether the previously reported inhibitory control- and cognitive flexibility-related performance costs for CWS are associated with the number of speech disfluencies that they produce.

METHOD

Participants were 19 CWS (Mage = 7.58 years, range: 6.08-9.17) and 19 CWNS matched on age and gender (Mage = 7.58 years, range: 6.08-9.33). Gamma regression models were used to investigate possible associations between performance costs in speed and accuracy measured during a computer task evaluating inhibitory control and cognitive flexibility and the number of speech disfluencies during video-recorded speech samples (story retelling and casual conversation).

RESULTS

Two significant interactions were observed. For both inhibitory control and cognitive flexibility, we identified a significant group and inhibitory control/cognitive flexibility performance-cost interaction in stuttering-like disfluencies (SLDs), indicating that the performance-cost effects on SLD production were significantly higher in the CWS group, compared to the CWNS group.

CONCLUSIONS

CWS with reduced inhibitory control or cognitive flexibility produce more SLDs, but not other disfluencies. These results are partly in line with some previous findings in nonstuttering and stuttering populations linking inhibitory control and cognitive flexibility weaknesses to the production of speech disfluencies.

A meta-analysis of cognitive flexibility in autism spectrum disorder

Cognitive flexibility is a fundamental process that underlies adaptive behaviour in response to environmental change. Studies examining the profile of cognitive flexibility in autism spectrum disorder (ASD) have reported inconsistent findings. To address whether difficulties with cognitive flexibility are characteristic of autism, we conducted a random-effects meta-analysis and employed subgroup analyses and meta-regression to assess the impact of relevant moderator variables such as task, outcomes, and age. Fifty-nine studies were included and comprised of 2122 autistic individuals without intellectual disabilities and 2036 neurotypical controls, with an age range of 4 to 85 years. The results showed that autistic individuals have greater difficulties with cognitive flexibility, with an overall statistically significant small to moderate effect size. Subgroup analyses revealed a significant difference between task outcomes, with perseverative errors obtaining the largest effect size. In summary, the present meta-analysis highlights the existence of cognitive flexibility difficulties in autistic people, in the absence of learning disabilities, but also that this profile is characterised by substantial heterogeneity. Potential contributing factors are discussed.

Habit-DisHabit Design with a Quadratic Equation: A Better Model of the Hemodynamic Changes in Preschoolers during the Dimension Change Card Sorting Task

General linear modeling (GLM) has been widely employed to estimate the hemodynamic changes observed by functional near infrared spectroscopy (fNIRS) technology, which are found to be nonlinear rather than linear, however. Therefore, GLM might not be appropriate for modeling the hemodynamic changes evoked by cognitive processing in developmental neurocognitive studies. There is an urgent need to identify a better statistical model to fit into the nonlinear fNIRS data. This study addressed this need by developing a quadratic equation model to reanalyze the existing fNIRS data (N = 38, Mage = 5.0 years, SD = 0.69 years, 17 girls) collected from the mixed-order design Dimensional Change Card Sort (DCCS) task and verified the model with a new set of data with the Habit-DisHabit design. First, comparing the quadratic and cubic modeling results of the mixed-order design data indicated that the proposed quadratic equation was better than GLM and cubic regression to model the oxygenated hemoglobin (HbO) changes in this task. Second, applying this quadratic model with the Habit-DisHabit design data verified its suitability and indicated that the new design was more effective in identifying the neural correlates of cognitive shifting than the mixed-order design. These findings jointly indicate that Habit-DisHabit Design with a quadratic equation might better model the hemodynamic changes in preschoolers during the DCCS task.

The use of functional near-infrared spectroscopy in tracking neurodevelopmental trajectories in infants and children with or without developmental disorders: a systematic review

Understanding the neurodevelopmental trajectories of infants and children is essential for the early identification of neurodevelopmental disorders, elucidating the neural mechanisms underlying the disorders, and predicting developmental outcomes. Functional Near-Infrared Spectroscopy (fNIRS) is an infant-friendly neuroimaging tool that enables the monitoring of cerebral hemodynamic responses from the neonatal period. Due to its advantages, fNIRS is a promising tool for studying neurodevelopmental trajectories. Although many researchers have used fNIRS to study neural development in infants/children and have reported important findings, there is a lack of synthesized evidence for using fNIRS to track neurodevelopmental trajectories in infants and children. The current systematic review summarized 84 original fNIRS studies and showed a general trend of age-related increase in network integration and segregation, interhemispheric connectivity, leftward asymmetry, and differences in phase oscillation during resting-state. Moreover, typically developing infants and children showed a developmental trend of more localized and differentiated activation when processing visual, auditory, and tactile information, suggesting more mature and specialized sensory networks. Later in life, children switched from recruiting bilateral auditory to a left-lateralized language circuit when processing social auditory and language information and showed increased prefrontal activation during executive functioning tasks. The developmental trajectories are different in children with developmental disorders, with infants at risk for autism spectrum disorder showing initial overconnectivity followed by underconnectivity during resting-state; and children with attention-deficit/hyperactivity disorders showing lower prefrontal cortex activation during executive functioning tasks compared to their typically developing peers throughout childhood. The current systematic review supports the use of fNIRS in tracking the neurodevelopmental trajectories in children. More longitudinal studies are needed to validate the neurodevelopmental trajectories and explore the use of these neurobiomarkers for the early identification of developmental disorders and in tracking the effects of interventions.

Viewing and playing fantastical events does not affect children's cognitive flexibility and prefrontal activation

Media exposure, such as viewing fantastical content, can have negative, immediate, and long-term effects on children's executive function. A recent study showed that watching fantastical content on a tablet can impair children's inhibitory control and prefrontal activation during the performance of a task. However, the same effect was not observed when children played fantastical games on a tablet. We aimed to replicate and extend this research by examining whether the same effects are observed during a cognitive flexibility task. In this study, preschool children (N = 32, 15 girls, Mean age in months (SD) = 60.6 (10)) viewed or played fantastical content on a tablet and performed a Dimensional Change Card Sort (DCCS) task before or after the media exposure. We assessed children's behavioral performance and prefrontal activation, as measured by functional near-infrared spectroscopy (fNIRS), and found no behavioral or neural changes after exposure. Our analyses using the Bayes factor supported the null hypothesis that children's cognitive flexibility is unaffected by watching or playing fantastical content.

Irritability Moderates the Association between Cognitive Flexibility Task Performance and Related Prefrontal Cortex Activation in Young Children

The association between cognitive flexibility and related neural functioning has been inconsistent. This is particularly true in young children, where previous studies have found heterogenous results linking behavior and neural function, raising the possibility of unexplored moderators. The current study explored the moderating role of dimensional irritability in the association between cognitive flexibility task performance and prefrontal activation in young children. A total of 106 3- to 7-year-old children were recruited to complete a custom-designed, child-adapted, cognitive flexibility task, and 98 of them were included in the data analysis. The children's dorsolateral prefrontal cortex activation was monitored using functional near-infrared spectroscopy, and their levels of irritability were reported by parents using the MAP-DB Temper Loss subscale. Results indicated that the mean reaction time of the cognitive flexibility task was negatively correlated with concurrent prefrontal activation. No evidence was found for the association between task accuracy and prefrontal activation. Moreover, irritability moderated the association between the mean reaction time and prefrontal activation. Children high in irritability exhibited a stronger negative association between the mean reaction time and related prefrontal activation than children low in irritability. The moderating model suggested a novel affective-cognitive interaction to investigate the associations between cognitive task performance and their neural underpinnings.

Evaluating the Distinction between Cool and Hot Executive Function during Childhood

This article assesses the cool-hot executive function (EF) framework during childhood. First, conceptual analyses suggest that cool EF (cEF) is generally distinguished from hot EF (hEF). Second, both EFs can be loaded into different factors using confirmatory factor analyses. Third, the cognitive complexity of EF is similar across cEF tasks, and the cognitive complexity of cEF is similar to hEF tasks. Finally, neuroimaging analysis suggests that children activate the lateral prefrontal regions during all EF tasks. Taken together, we propose that the cool-hot framework is a useful, though not definitive way of characterizing differences in EF.

Infant excitation/inhibition balance interacts with executive attention to predict autistic traits in childhood

BACKGROUND

Autism is proposed to be characterised by an atypical balance of cortical excitation and inhibition (E/I). However, most studies have examined E/I alterations in older autistic individuals, meaning that findings could in part reflect homeostatic compensation. To assess the directionality of effects, it is necessary to examine alterations in E/I balance early in the lifespan before symptom emergence. Recent explanatory frameworks have argued that it is also necessary to consider how early risk features interact with later developing modifier factors to predict autism outcomes.

METHOD

We indexed E/I balance in early infancy by extracting the aperiodic exponent of the slope of the electroencephalogram (EEG) power spectrum ('1/f'). To validate our index of E/I balance, we tested for differences in the aperiodic exponent in 10-month-old infants with (n = 22) and without (n = 27) neurofibromatosis type 1 (NF1), a condition thought to be characterised by alterations to cortical inhibition. We then tested for E/I alterations in a larger heterogeneous longitudinal cohort of infants with and without a family history of neurodevelopmental conditions (n = 150) who had been followed to early childhood. We tested the relevance of alterations in E/I balance and our proposed modifier, executive attention, by assessing whether associations between 10-month aperiodic slope and 36-month neurodevelopmental traits were moderated by 24-month executive attention. Analyses adjusted for age at EEG assessment, sex and number of EEG trials.

RESULTS

Infants with NF1 were characterised by a higher aperiodic exponent, indicative of greater inhibition, supporting our infant measure of E/I. Longitudinal analyses showed a significant interaction between aperiodic slope and executive attention, such that higher aperiodic exponents predicted greater autistic traits in childhood, but only in infants who also had weaker executive functioning abilities.

LIMITATIONS

The current study relied on parent report of infant executive functioning-type abilities; future work is required to replicate effects with objective measures of cognition.

CONCLUSIONS

Results suggest alterations in E/I balance are on the developmental pathway to autism outcomes, and that higher executive functioning abilities may buffer the impact of early cortical atypicalities, consistent with proposals that stronger executive functioning abilities may modify the impact of a wide range of risk factors.

Cognitive flexibility in younger and older children who stutter

PURPOSE

Recent research findings suggest possible weaknesses in cognitive flexibility (CF) in children who stutter (CWS) when compared to children who do not stutter (CWNS). Studies so far, have been conducted with either younger (3-6 years old) or older children (6-12 years old) with a variety of measures. The purpose of the present study was to investigate CF with the use of a single behavioral measure across a broader age range (4-10 years old).

METHODS

Participants were 37 CWS (mean age = 6.90 years) and 37 age-and gender-matched CWNS (mean age = 6.88 years), divided in a younger (below 7 years) and older (above 7 years) age group. All participants undertook a computerized visual set-shifting task consisting of three blocks. CF was evaluated through across-and within-block comparisons of the actual response speed and accuracy values. In addition, mixing-and set-shifting-costs were evaluated based on the mean response speed and accuracy.

RESULTS

All participants showed expected mixing-and set-shifting-costs. Only the within-block analyses yielded significant between (sub)group differences. Investigation of the block × classification group × age group interactions showed that older CWS had larger set-shifting-costs (slowed down more and made more errors) compared to older CWNS.

CONCLUSION

While all participants required more time during set-shifting trials, only the older CWS (7-10 years old), and not younger CWS, were slower and made more errors. This finding corroborates previous findings in CWS of a similar age and could possibly point to a role of CF in stuttering persistence.

Longitudinal investigation of executive function development employing task-based, teacher reports, and fNIRS multimethodology in 4- to 5-year-old children

Increased focus on resting-state functional connectivity (rsFC) and the use and accessibility of functional near-infrared spectroscopy (fNIRS) have advanced knowledge on the interconnected nature of neural substrates underlying executive function (EF) development in adults and clinical populations. Less is known about the relationship between rsFC and developmental changes in EF during preschool years in typically developing children, a gap the present study addresses employing task-based assessment, teacher reports, and fNIRS multimethodology. This preregistered study contributes to our understanding of the neural basis of EF development longitudinally with 41 children ages 4-5. Changes in prefrontal cortex (PFC) rsFC utilizing fNIRS, EF measured with a common task-based assessment (Day-Night task), and teacher reports of behavior (BRIEF-P) were monitored over multiple timepoints: Initial Assessment, 72 h follow-up, 1 Month Follow-up, and 4 Month Follow-up. Measures of rsFC were strongly correlated 72 h apart, providing evidence of high rsFC measurement reliability using fNIRS with preschool-aged children. PFC rsFC was positively correlated with performance on task-based and report-based EF assessments. Children's PFC functional connectivity at rest uniquely predicted later EF, controlling for verbal IQ, age, and sex. Functional connectivity at rest using fNIRS may potentially show the rapid changes in EF development in young children, not only neurophysiologically, but also as a correlate of task-based EF performance and ecologically-relevant teacher reports of EF in a classroom context.

Direct and indirect effects on child neurocognitive development when maternal cancer is diagnosed during pregnancy: What do we know so far?

Cancer during pregnancy threatens the lives of mother and foetus and its incidence is rising, making it an emerging medical challenge. Evidence on the direct impact of cancer therapies on neonatal outcomes resulted in general guidelines for maternal treatment that safeguards foetal development. Less focus has been placed on indirect factors, in pre- and postnatal periods, that may exert long-term impacts specifically on child neurocognition. Foetal development, in the context of maternal cancer during pregnancy, may be influenced directly by exposure to cancer diagnostics and (co-)treatment, or indirectly through maternal inflammation, malnutrition, hormonal fluctuations, prematurity, and psycho-biological stress. Maternal stress and insecure mother-infant bonding related to postpartum cancer treatment may further impact child cognitive-behavioural development. Understanding the independent and synergistic effects of the factors impacting neurocognitive development creates the opportunity to intervene during the oncological treatment to improve the child's long-term outcome, both by medical and psychosocial care and support.

Age-Related Variance in Performance versus Ratings of Attention and Impulse Regulation in Children: Implications for the Assessment of ADHD

Executive function task (EF) deficits are hypothesized to underlie difficulties with self-regulation. However, tasks assessing EF impairments have only been weakly correlated with rating scales that index self-regulation difficulties. A community sample of children and youth aged between 8 and 20 years old were assessed longitudinally. Growth curve analyses and correlations were conducted to better understand how these two types of measures relate to one another across development, as well as the impact of age-related variance. EF was assessed using the Stroop Task and Trail Making test and behavioral ratings of self-regulation were captured using the SWAN scale. EF task performance improved steeply until age 14–15, whereas the SWAN Scale showed small age-related decreases. EF task performance was moderately correlated with age among 8–13-year-olds and to a lesser extent among 14–20-year-olds. SWAN scores were not significantly related to age in either group. Correlations were similar in an ADHD “at-risk” subgroup. EF task performance and parent ratings of attention regulation have different developmental trajectories, which may partly explain why correlations are low to modest in these samples. In particular, age-related variance is an important methodological consideration with significant implications for the assessment of self-regulation in children and youth with ADHD.

Structural and functional variations in the prefrontal cortex are associated with learning in pre-adolescent common marmosets (Callithrix jacchus)

There is substantial evidence linking the prefrontal cortex (PFC) to a variety of cognitive abilities, with adolescence being a critical period in its development. In the current study, we investigated the neural basis of differences in learning in pre-adolescent common marmosets. At 8 months old, marmosets were given anatomical and resting state MRI scans (n=24). At 9 months old, association learning and inhibitory control was tested using a 'go/no go' visual discrimination (VD) task. Marmosets were grouped into 'learners' (n=12) and 'non-learners' (n=12), and associations between cognitive performance and sub-regional PFC volumes, as well as PFC connectivity patterns, were investigated. 'Learners' had significantly (p<0.05) larger volumes of areas 11, 25, 47 and 32 than 'non-learners', although 'non-learners' had significantly larger volumes of areas 24a and 8v than 'learners'. There was also a significant correlation between average % correct responses to the 'punished' stimulus and volume of area 47. Further, 'non-learners' had significantly greater global PFC connections, as well as significantly greater numbers of connections between the PFC and basal ganglia, cerebellum and hippocampus, compared to 'non-learners'. These results suggest that larger sub-regions of the orbitofrontal cortex and ventromedial PFC, as well more refined PFC connectivity patterns to other brain regions associated with learning, may be important in successful response inhibition. This study therefore offers new information on the neurodevelopment of individual differences in cognition during pre-adolescence in non-human primates.

Differential Relations of Parental Behavior to Children's Early Executive Function as a Function of Child Genotype: A Systematic Review

Child genotype is an important biologically based indicator of sensitivity to the effects of parental behavior on children's executive function (EF) in early childhood, birth to age 5. While evidence for gene × parental behavior interactions on children's early EF is growing, researchers have called the quality of evidence provided by gene × environment interaction studies into question. For this reason, this review comprehensively examined the literature and evaluated the evidence for gene × parental behavior interactions on children's early EF abilities. Psychology and psychiatry databases were searched for published peer-reviewed studies. A total of 18 studies met inclusion criteria. Twenty-nine of 89 (33%) examined interactions were significant. However, a p-curve analysis did not find the significant interactions to be of evidential value. A high rate of false positives, due to the continued use of candidate gene and haplotype measures of child genotype and small sample sizes, likely contributed to the high rate of significant interactions and low evidential value. The use of contemporary molecular genetic measures and larger sample sizes are necessary to advance our understanding of child genotype as a moderator of parental effects on children's EF during early childhood and the biopsychosocial mechanisms underlying children's EF development during this critical period. Without these changes, future research is likely to be stymied by the same limitations as current research.

The neurobehavioral relationship between executive function and creativity during early childhood

Increasing evidence from behavior and neuroimaging research indicates that executive function (EF) is related to creativity. However, most of these studies focused on adult and adolescent populations. The relationship between EF and creativity is unknown when EF undergoes rapid development during early childhood, due to the preschoolers' marginal skills of expressing their ideas, orally or in writing. Using a nonverbal, open-ended test, the present study examined whether creative thinking was related to cognitive flexibility in young children. Preschool children (N = 26) performed the Dimensional Change Card Sort (DCCS) and the Unusual Box Test (UBT), while their brain activation was recorded using functional near-infrared spectroscopy (fNIRS). We did not find any significant correlation between children's cognitive flexibility and creative thinking. However, fNIRS analyses showed that children's brain activation in the lateral prefrontal regions was significantly greater during the test phases of the UBT. Additionally, children who strongly recruited their ventrolateral prefrontal regions during the post-switch phases of the DCCS recruited the same regions while performing the UBT. Taken together, these findings suggest that children recruit their lateral prefrontal regions when expressing creative thinking, and that such creative thinking could be partially supported by cognitive flexibility in early childhood.

Links between socioeconomic disadvantage, neural function, and working memory in early childhood

Children reared in socioeconomically disadvantaged environments are at risk for academic, cognitive, and behavioral problems. Mounting evidence suggests that childhood adversities, encountered at disproportionate rates in contexts of socioeconomic risk, shape the developing brain in ways that explain disparities. Circuitries that subserve neurocognitive functions related to memory, attention, and cognitive control are especially affected. However, most work showing altered neural function has focused on middle childhood and adolescence. Understanding alterations in brain development during foundational points in early childhood is a key next step. To address this gap, we examined functional near-infrared-spectroscopy-based neural activation during a working memory (WM) task in young children aged 4-7 years (N = 30) who varied in socioeconomic risk exposure. Children who experienced greater disadvantage (lower income to needs ratio and lower Hollingshead index) exhibited lower activation in the lateral prefrontal cortex than children who experienced less to no disadvantage. Variability in prefrontal cortex activation, but not behavioral performance on the WM task, was associated with worse executive functioning in children as reported by parents. These findings add to existing evidence that exposure to early adversity, such as socioeconomic risk, may lead to foundational changes in the developing brain, which increases risk for disparities in functioning across multiple cognitive and social domains.

Relationship between cool and hot executive function in young children: A near-infrared spectroscopy study

A theoretical distinction exists between the cool and hot aspects of executive function (EF). At the neural level, cool EF may be associated with activation in the lateral prefrontal cortex and the anterior cingulate cortex, whereas the orbitofrontal cortex may play a key role in hot EF. However, some recent studies have shown that young children show activity in the lateral prefrontal regions during hot EF tasks, suggesting that the distinction between hot and cool EF may not be as marked. Nevertheless, few neuroimaging studies have directly examined the relationship between cool and hot EF. In this study, preschool children (N = 46, mean age = 66.1 months) were given both cool (Dimensional Change Card Sort (DCCS) and Stroop-like tasks) and hot (delay of gratification) EF tasks, and neural activation during these tasks was measured using functional near-infrared spectroscopy (fNIRS). Correlational analyses and analysis of variance (ANOVA) were conducted to assess the relationship between cool and hot EF. At the behavioral level, a moderate correlation was found between DCCS and Stroop-like tasks, but no correlation emerged between cool and hot EF tasks. At the neural level, prefrontal activations during the cool EF tasks did not correlate with those during the hot EF task. Further, children showed stronger prefrontal activations during the DCCS tasks compared to the delay of gratification tasks. The results suggest that the neural basis of hot and cool EF may differ during early childhood.

Tablet Use Affects Preschoolers' Executive Function: fNIRS Evidence from the Dimensional Change Card Sort Task

This study aims to examine the impact of heavy use of tablets on preschoolers’ executive function during the Dimensional Change Card Sort (DCCS) task using the functional near-infrared spectroscopy (fNIRS). Altogether, 38 Chinese preschoolers (M_age = 5.0 years, SD = 0.69 years, 17 girls) completed the tasks before the COVID-19 lockdown. Eight children never used tablets, while 16 children were diagnosed as the ‘heavy-user’. The results indicated that: (1) the ‘non-user’ outperformed the ‘heavy-user’ with a significantly higher correct rate in the DCCS task; (2) the two groups differed significantly in the activation of the prefrontal cortex (BA 9): the ‘non-user’ pattern is normal and healthy, whereas the ‘heavy-user’ pattern is not normal and needs further exploration.

The acute effect of moderate-intensity exercise on inhibitory control and activation of prefrontal cortex in younger and older adults

Exercise has a significant effect on maintaining the health of inhibitory function, a fundamental cognitive ability that supports daily mental processes. While previous studies have shown that a single bout of exercise, called acute exercise, could improve inhibitory control by stimulating the prefrontal cortex (PFC) and the arousal state, few studies have focused on the differences in the effects of exercise by age. In this study, young and older adults (mean age, 22.7 ± 1.4 and 68.7 ± 5.3 years, respectively) engaged in acute moderate-intensity exercise and inhibitory control. Before and at 5 and 30 min after exercise, the participants were asked to complete the reverse Stroop task, and their arousal state and PFC activity were measured using functional near-infrared spectroscopy. The findings showed that the overall inhibitory control improved immediately after performing acute exercise and remained improved even after 30 min. Particularly, there was a difference in the arousal state and middle PFC activity between the two age groups. Especially, the young adults showed an increase in the arousal state post-exercise, while the older adults tended to show an increase in the middle PFC activity. These results suggested that the acute exercise effects on the arousal state and PFC activity may vary depending on the developmental stage, but not for inhibitory control overtime. When these findings are considered, it is important to note that the exercise impact on cognitive control remained the same throughout the generations despite the observed changes in its impact on internal states.

Targeting brain regions of interest in functional near-infrared spectroscopy-Scalp-cortex correlation using subject-specific light propagation models

Targeting specific brain regions of interest by the accurate positioning of optodes (emission and detection probes) on the scalp remains a challenge for functional near‐infrared spectroscopy (fNIRS). Since fNIRS data does not provide any anatomical information on the brain cortex, establishing the scalp‐cortex correlation (SCC) between emission‐detection probe pairs on the scalp and the underlying brain regions in fNIRS measurements is extremely important. A conventional SCC is obtained by a geometrical point‐to‐point manner and ignores the effect of light scattering in the head tissue that occurs in actual fNIRS measurements. Here, we developed a sensitivity‐based matching (SBM) method that incorporated the broad spatial sensitivity of the probe pair due to light scattering into the SCC for fNIRS. The SCC was analyzed between head surface fiducial points determined by the international 10–10 system and automated anatomical labeling brain regions for 45 subject‐specific head models. The performance of the SBM method was compared with that of three conventional geometrical matching (GM) methods. We reveal that the light scattering and individual anatomical differences in the head affect the SCC, which indicates that the SBM method is compulsory to obtain the precise SCC. The SBM method enables us to evaluate the activity of cortical regions that are overlooked in the SCC obtained by conventional GM methods. Together, the SBM method could be a promising approach to guide fNIRS users in designing their probe arrangements and in explaining their measurement data.

A Dynamical Reconceptualization of Executive-Function Development

Executive function plays a foundational role in everyday behaviors across the life span. The theoretical understanding of executive-function development, however, is still a work in progress. Doebel proposed that executive-function development reflects skills using control in the service of behavior-using mental content such as knowledge and beliefs to guide behavior in a context-specific fashion. This liberating view contrasts with modular views of executive function. This new view resembles some older dynamic-systems concepts that long ago proposed that behavior reflects the assembly of multiple pieces in context. We dig into this resemblance and evaluate what else dynamic-systems theory adds to the understanding of executive-function development. We describe core dynamic-systems concepts and apply them to executive function-as conceptualized by Doebel-and through this lens explain the multilevel nature of goal-directed behavior and how a capacity to behave in a goal-directed fashion across contexts emerges over development. We then describe a dynamic systems model of goal-directed behavior during childhood and, finally, address broader theoretical implications of dynamic-systems theory and propose new translational implications for fostering children's capacity to behave in a goal-directed fashion across everyday contexts.

Neural Basis of Scale Errors in Young Children

In this study, we examined whether 2-and 3-year-old children exhibited activation in the dorsolateral and ventrolateral prefrontal regions while engaging in a tool-based scale error task as measured by near-infrared spectroscopy. Results revealed no significant differences in the prefrontal activation between children who produced scale errors and those who did not. However, we found significant activations of the prefrontal region during scale error sessions compared to free play sessions. Our results do not deny that the activation of prefrontal regions may, at least in part, be associated with children's scale error.

Neural basis for egalitarian sharing in five-to six-year-old children

Preferring fair resource distribution reflects human cooperative nature, but its neural correlates in young children are not well known. We investigated the neural mechanism of egalitarian resource sharing in five-to six-year-old children to examine the possibility that early egalitarianism requires behavioral control to inhibit selfish impulses. In Study 1, children participated in a behavioral control task in which they either needed or did not need to inhibit their impulsive behavioral responses in order to quickly press a key. They subsequently allocated their resources to strangers by choosing a 2:2, 3:1, or 4:0 distribution. The activation of the dorsolateral prefrontal (dlpfc) regions was recorded by functional near-infrared spectroscopy measurements. We found that dlpfc regions were activated during cognitive tasks involving behavioral control and also during the equal, but not the more selfish, allocations. There was no difference among these allocations. The results did not show evidence of an ego depletion effect on children's sharing behavior, which predicts that children will share less after their behavioral control is taxed in a cognitive task (i.e., their self-control resource depleted). Study 2 showed no activation of the dlpfc regions during third-party equal allocations in which there was no conflict between fairness and self-interest in the distribution of resources. Overall, we showed that costly equal sharing in young children relates to the activation of dlpfc regions. These results suggest that costly equal allocation has a common neural basis with behavioral control in five-to six-year-old children, implying that early egalitarian sharing requires dealing with conflicts between maximizing self-interest and following moral norms.

A Functional Near-Infrared Spectroscopy Examination of the Neural Correlates of Cognitive Shifting in Dimensional Change Card Sort Task

This study aims to examine the neural correlates of cognitive shifting during the Dimensional Change Card Sort Task (DCCS) task with functional near-infrared spectroscopy. Altogether 49 children completed the DCCS tasks, and 25 children (Mage = 68.66, SD = 5.3) passing all items were classified into the Switch group. Twenty children (M age = 62.05, SD = 8.13) committing more than one perseverative errors were grouped into the Perseverate group. The Switch group had Brodmann Area (BA) 9 and 10 activated in the pre-switch period and BA 6, 9, 10, 40, and 44 in the post-switch period. In contrast, the Perseverate group had BA 9 and 10 activated in the pre-switch period and BA 8, 9, 10 in the post-switch period. The general linear model results afford strong support to the "V-shape curve" hypothesis by identifying a significant decrease-increase cycle in BA 9 and 44, the neural correlations of cognitive shifting.

Roles of culture and COMT Val58Met gene on neural basis of executive function: A comparison between Japanese and American children

The development of executive functions (EF) is shaped by both genetic and environmental factors, including cultural background. Genetically, variation in the catechol-O-methyltransferase (COMT) gene polymorphism has been linked to EF performance and differential regulation of prefrontal cortex activity. Based on the gene-culture interaction framework, we tested whether culture would moderate the association between the COMT gene and young children's behavioral responses and neural activities during a cognitive-shifting EF task. The children who participated in this study were 5- to 6-year-olds in Japan (n = 44) and in the U.S. (n = 47). The results revealed that U.S.-American children exhibited stronger activations than Japanese children in the right dorsolateral and bilateral prefrontal cortex regions. In addition, the children's genetic disposition and EF performance were marginally moderated by culture, with Val homozygote Japanese children performing better than Met-allele carriers, whereas no such differences were found in U.S.-American children. We have discussed the theoretical and empirical implications of the construction of a more complete understanding of EF development by incorporating both genetic and socio-cultural factors.

Neural Correlates of Mental Rotation in Preschoolers With High or Low Working Memory Capacity: An fNIRS Study

This study explored the differentiated neural correlates of mental rotation (MR) in preschoolers with high and low working memory capacity using functional near-infrared spectroscopy (fNIRS). Altogether 38 Chinese preschoolers (M = 5.0 years, SD = 0.69 years) completed the Working Memory Capacity (WMC) test, the Mental Rotation (MR), and its Control tasks (without MR). They were divided into High-WMC (N₁ = 9) and Low-WMC (N₂ = 18) groups based on the WMC scores. The behavioral and fNIRS results indicated that: (1) there were no significant differences in MR task performance between the High-WMC (M_mr = 23.44, SD = 0.88) and Low-WMC group (M_mr = 23.67, SD = 0.59); (2) the Low-WMC group activated BA6, BA8, BA 9, and BA 44, whereas the High-WMC group activated BA8, BA10 and BA 44 during mental rotation; (3) significant differences were found in the activation of BA44 and BA9 between the High-WMC and Low-WMC groups during mental rotation; and (4) the High-WMC and Low-WMC groups differed significantly in the activation of BA 9 and BA10 during the control tasks, indicating that both areas might be responsible for the group differences in working memory.

Viewing Fantastical Events in Animated Television Shows: Immediate Effects on Chinese Preschoolers' Executive Function

Three experiments were conducted to test whether watching an animated show with frequent fantastical events decreased Chinese preschoolers’ post-viewing executive function (EF), and to test possible mechanisms of this effect. In all three experiments, children were randomly assigned to watch a video with either frequent or infrequent fantastical events; their EF was immediately assessed after viewing, using behavioral measures of working memory, sustained attention, and cognitive flexibility. Parents completed a questionnaire to assess preschoolers’ hyperactivity level as a potential confounding variable. In Experiment 1 (N = 90), which also included a control group, there was an immediate negative effect of watching frequent fantastical events, as seen in lower scores on the behavioral EF tasks. In Experiment 2 (N = 20), eye tracking data showed more but shorter eye fixations in the high frequency group, suggesting a higher demand on cognitive resources; this group also did more poorly on behavioral measures of EF. In Experiment 3 (N = 20), functional near-infrared spectroscopy (fNIRS) data showed that the high frequency group had a higher concentration of oxygenated hemoglobin (Coxy-Hb), an indicator of higher brain activation consistent with a greater use of cognitive resources; this group also had lower scores on the behavioral EF tasks. The findings are discussed in reference to models of limited cognitive resources.

An optical window into brain function in children and adolescents: A systematic review of functional near-infrared spectroscopy studies

Despite decades of research, our understanding of functional brain development throughout childhood and adolescence remains limited due to the challenges posed by certain neuroimaging modalities. Recently, there has been a growing interest in using functional near-infrared spectroscopy (fNIRS) to elucidate the neural basis of cognitive and socioemotional development and identify the factors shaping these types of development. This article, focusing on the fNIRS methods, presents an up-to-date systematic review of fNIRS studies addressing the effects of age and other factors on brain functions in children and adolescents. Literature searches were conducted using PubMed and PsycINFO. A total of 79 fNIRS studies involving healthy individuals aged 3-17 years that were published in peer-reviewed journals in English before July 2020 were included. Six methodological aspects of these studies were evaluated, including the research design, experimental paradigm, fNIRS measurement, data preprocessing, statistical analysis, and result presentation. The risk of bias, such as selective outcome reporting, was assessed throughout the review. A qualitative synthesis of study findings in terms of the factor effects on changes in oxyhemoglobin concentration was also performed. This unregistered review highlights the strengths and limitations of the existing literature and suggests directions for future research to facilitate the improved use of fNIRS in developmental cognitive neuroscience research.

Applied Machine Learning Method to Predict Children With ADHD Using Prefrontal Cortex Activity: A Multicenter Study in Japan

Objective: To establish valid, objective biomarkers for ADHD using machine learning. Method: Machine learning was used to predict disorder severity from new brain function data, using a support vector machine (SVM). A multicenter approach was used to collect data for machine learning training, including behavioral and physiological indicators, age, and reverse Stroop task (RST) data from 108 children with ADHD and 108 typically developing (TD) children. Near-infrared spectroscopy (NIRS) was used to quantify change in prefrontal cortex oxygenated hemoglobin during RST. Verification data were from 62 children with ADHD and 37 TD children from six facilities in Japan. Results: The SVM general performance results showed sensitivity of 88.71%, specificity of 83.78%, and an overall discrimination rate of 86.25%. Conclusion: A SVM using an objective index from RST may be useful as an auxiliary biomarker for diagnosis for children with ADHD.

Exploring the Benefits of Doll Play Through Neuroscience

It has long been hypothesized that pretend play is beneficial to social and cognitive development. However, there is little evidence regarding the neural regions that are active while children engage in pretend play. We examined the activation of prefrontal and posterior superior temporal sulcus (pSTS) regions using near-infrared spectroscopy while 42 4- to 8-year-old children freely played with dolls or tablet games with a social partner or by themselves. Social play activated right prefrontal regions more than solo play. Children engaged the pSTS during solo doll play but not during solo tablet play, suggesting they were rehearsing social cognitive skills more with dolls. These findings suggest social play utilizes multiple neural regions and highlight how doll play can achieve similar patterns of activation, even when children play by themselves. Doll play may provide a unique opportunity for children to practice social interactions important for developing social-emotional skills, such as empathy.

Time-Based Measures of Monitoring in Association With Executive Functions in Kindergarten Children

Abstract. Repeatedly, the notion has been put forward that metacognition (MC) and executive functions (EF) share common grounds, as both describe higher order cognitive processes and involve monitoring. However, only few studies addressed this issue empirically and so far their findings are rather inconsistent. Addressing the question whether measurement differences may in part be responsible for the mixed results, the current study included explicitly reported as well as time-based measures of metacognitive monitoring and related them to EF. A total of 202 children aged 4–6 years were assessed in terms of EF (inhibition, working memory, shifting) and monitoring. While there was no significant link between explicitly reported confidence and EF, latencies of monitoring judgments were significantly related to time- and accuracy-based measures of EF. Our findings support the association between EF and MC and the assumption that better inhibition abilities help children to engage in more thorough monitoring.

Are there sex differences in the development of prefrontal function during early childhood?

Research has demonstrated the possibility of minor sex differences in executive function (EF) development of young children; however, this may be limited to the measurements used in previous studies (questionnaires and cognitive tasks), which tend to be less sensitive to the detection of sex differences. The present study uses brain measures to examine the effect of sex on EF development. In this study, preschool children were given an EF task, and patterns of activation in the lateral prefrontal regions were measured by a functional near-infrared spectroscopy. In Study 1, there were no behavioral differences between girls and boys, though girls showed stronger prefrontal activation than boys. Study 2 was conducted as an attempt to replicate the results, and some of the results were inconsistent with the results in Study 1. Results suggest that sex differences in EF tasks are small, although such differences may exist irrespective of methodology.

Effects of social and nonsocial reward on executive function in preschoolers

INTRODUCTION

Executive function, a set of higher order cognitive skills underlying goal-directed behaviors, develops rapidly during preschool years. Reward increases executive function engagement in adolescents and adults. However, there is still a scarcity of data on how reward affects executive function in young children. The present study examines whether different incentive types contribute differently to executive function performance and neural activity in children.

METHODS

Twenty-five preschoolers of 5-6 years old were provided an incentive Go/No-go task, comparing social, nonsocial, and nonreward conditions. Activations in the prefrontal regions during the tasks were measured using functional near-infrared spectroscopy.

RESULTS

The results revealed that social reward enhanced right prefrontal activations in young children. In contrast to adult literature, younger children did not show any significant differences in executive function performance across conditions.

CONCLUSION

This study expands our understanding of motivation and EF engagement in preschoolers. Specifically, social reward enhanced prefrontal activations in young children. The implications and recommendations for future research are discussed.

Cognitive and neural underpinnings of goal maintenance in young children

Active maintenance of goal representations is an integral part of our mental regulatory processes. Previous developmental studies have highlighted goal neglect, which is the phenomenon caused by a failure to maintain goal representations, and demonstrated developmental changes of the ability to maintain goal representations among preschoolers. Yet, few studies have explored the cognitive mechanisms underlying preschoolers' development of goal maintenance. The first aim of this study was to test whether working memory capacity and inhibitory control contribute to goal maintenance using a paradigm for measuring goal neglect. Moreover, although recent studies have shown that preschoolers recruit lateral prefrontal regions in performing executive functions tasks, they could not specify the neural underpinnings of goal maintenance. Thus, the second aim was to examine whether lateral prefrontal regions played a key role in maintaining goal representations using functional near-infrared spectroscopy. Our results showed that developmental differences in inhibitory control predicted the degree of goal neglect. It was also demonstrated that activation in the right prefrontal region was associated with children's successful avoidance of goal neglect. These findings offer important insights into the cognitive and neural underpinnings of goal maintenance in preschoolers.

Exploring the neural basis of selective and flexible dimensional attention: An fNIRS study

Between the ages of 3 and 5, children develop greater control over attention to visual dimensions. Children develop the ability to flexibly shift between visual dimensions and to selectively process specific dimensions of an object. Previous proposals have suggested that selective and flexible attention are developmentally related to one another (e.g., Hanania & Smith, 2010). However, the relationship between flexibility and selectivity has not been systematically probed at the behavioral and neural levels. We administered a selective attention task (triad classification) along with a flexible attention task (dimensional change card sort) with 3.5- and 4.5-year-olds while functional near-infrared spectroscopy data were recorded. Results showed that children with high flexible attention skills engaged bilateral frontal cortex which replicates previous studies using this task. Moreover, children with high levels of selective attention engaged right frontal cortex. Together, these results indicate that development in right frontal cortex is important for both flexible and selective dimensional attention.

Bilingualism, Demographics, and Cognitive Control: A Within-Group Approach

Previous studies have suggested a bilingual advantage in cognitive control as a result of the bilinguals’ language experience. However, the results are controversial as there are various factors (language proficiency, SES, culture, and intelligence, etc.) affecting cognitive control. In the current study, after between-group comparisons, we adopted a within-group approach by multiple regressions to investigate whether the performance by 10-to-75-year-old participants (N = 91) of tasks measuring inhibition, monitoring, and mental set shifting could be predicted by bilingualism, or demographic factors, or both. The results of multiple stepwise regression analyses showed that L2 proficiency was a significant predictor for conflict monitoring and inhibition, education and age were significant predictors for mental set shifting, and SES was a minor predictor for inhibition. These findings provide evidence that cognitive control is affected by both bilingualism and demographic factors. Future studies are encouraged to further identify the relationship between bilingualism and cognitive control from specific bilingual experience.

Smiling enemies: Young children better recall mean individuals who smile

Remembering whether a person is cooperative is essential in social interactions. It has been shown that adults have better memory of a person who showed an incongruence between emotional expression and expected behavior (e.g., smiling while stealing). To examine whether children would show similar emotional incongruity effects, we examined 70 children aged 5 or 6 years. They obtained coins that could be exchanged later for rewards (stickers) by answering quiz questions. Then, they participated in the coin collection game where individual persons with smiling or angry expressions appeared one at a time on a computer monitor. These same individuals then either gave coins to or took coins away from the children, leading to congruent (smiling giver and angry taker) and incongruent (smiling taker and angry giver) conditions. After the game, children needed to choose between two faces to indicate which one previously appeared in the game. Participants recognized faces better under the incongruent conditions. In particular, the smiling taker was recognized significantly better than the angry taker, whereas no difference was observed for the smiling and angry givers. Evidently, 5- and 6-year-olds better remember individuals whose facial expression or appearance is incongruent with their expected behavior.

Cognitive flexibility-related prefrontal activation in preschoolers: A biological approach to temperamental effortful control

Individual differences in temperament have been theorized to be supported by differential recruitment of key neural regions, resulting in the distinct patterns of behavior observed throughout life. Although a compelling model, its rigorous and systematic testing is lacking, particularly within the heightened neuroplasticity of early childhood. The current study tested a model of the link between temperament, the brain, and behavior for cognitive flexibility in a sample of 4-5-year-old children (N = 123) using functional near-infrared spectroscopy (fNIRS) to assess prefrontal cortex (PFC) activation. Structural Equation Modeling (SEM) was used to explore the link between survey reports of temperamental effortful control, and both performance-based and neuroimaging measures of cognitive flexibility. Results indicated that greater parent-reported temperamental effortful control was associated with better performance on a cognitive flexibility task, and less activation of the DLPFC in preschoolers. These findings support the theorized model of the interrelatedness between temperamental tendencies, behavior, and brain activation and suggest that better temperamentally regulated children use the DLPFC more efficiently for cognitive flexibility.

Age-related differences in frontal lobe function in children with ADHD

BACKGROUND

The neural correlates of executive function disorders are thought to be predominantly localized within the prefrontal cortex (PFC). However, no study to date has investigated changes in this system across different age groups in children with attention deficit hyperactivity disorder (ADHD). Thus, this study aimed to explore changes in PFC function in children with ADHD.

METHODS

Study participants included typically developing (TD) children (n = 140) and children with ADHD (n = 67) of primary school age. Behavioral executive functions and their neural basis were evaluated between the TD children and children with ADHD and also across different age periods (younger and older children). To examine executive function, inhibitory control was assessed using the reverse Stroop task, and PFC near-infrared spectroscopic measurements were used to investigate the neural mechanisms involved.

RESULTS

Both ADHD symptoms and the ability to inhibit color interference improved with age. Compared to TD children, children with ADHD demonstrated decreased activation of the right and middle PFC across all age groups. Interestingly, the left PFC appeared to play a compensatory role.

CONCLUSION

Children with ADHD exhibited changes in PFC function that varied with age. Longitudinal studies are required to assess the potential of using PFC function as an early biomarker of ADHD.

Dimensional attention as a mechanism of executive function: Integrating flexibility, selectivity, and stability

In this report, we present a neural process model that explains visual dimensional attention and changes in visual dimensional attention over development. The model is composed of an object representation system that binds visual features such as shape and color to spatial locations and a label learning system that associates labels such as "color" or "shape" with visual features. We have previously demonstrated that this model explains the development of flexible dimensional attention in a task that requires children to switch between shape and color rules for sorting cards. In the model, the development of flexible dimensional attention is a product of strengthening associations between labels and features. In this report, we generalize this model to also explain development of stable and selective dimensional attention. Specifically, we use the model to explain a previously reported developmental association between flexible dimensional attention and stable dimensional attention. Moreover, we generate predictions regarding developmental associations between flexible and selective dimensional attention. Results from an experiment with 3- and 4-year-olds supported model predictions: children who demonstrated flexibility also demonstrated higher levels of selectivity. Thus, the model provides a framework that integrates various functions of dimensional attention, including implicit and explicit functions, over development. This model also provides new avenues of research aimed at uncovering how cognitive functions such as dimensional attention emerge from the interaction between neural dynamics and task structure, as well as understanding how learning dimensional labels creates changes in dimensional attention, brain activation, and neural connectivity.

Neural substrates of early executive function development

In the last decade, advances in neuroimaging technologies have given rise to a large number of research studies that investigate the neural underpinnings of executive function (EF). EF has long been associated with the prefrontal cortex (PFC) and involves both a unified, general element, as well as the distinct, separable elements of working memory, inhibitory control and set shifting. We will highlight the value of utilising advances in neuroimaging techniques to uncover answers to some of the most pressing questions in the field of early EF development. First, this review will explore the development and neural substrates of each element of EF. Second, the structural, anatomical and biochemical changes that occur in the PFC during infancy and throughout childhood will be examined, in order to address the importance of these changes for the development of EF. Third, the importance of connectivity between regions of the PFC and other brain areas in EF development is reviewed. Finally, throughout this review more recent developments in neuroimaging techniques will be addressed, alongside the implications for further elucidating the neural substrates of early EF development in the future.

Differentiation in prefrontal cortex recruitment during childhood: Evidence from cognitive control demands and social contexts

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Using fNIRS, we examined how children recruit PFC while engaging cognitive control.

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Activation increased with cognitive control demands more in left than right PFC.

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It was higher in left PFC in competitive than cooperative contexts, and in right PFC in cooperative and neutral compared to competitive contexts.

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Older children showed greater variations in PFC activation than younger children.

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Cognitive control is supported by more differentiated PFC recruitment with age.

Emerging cognitive control during childhood is largely supported by the development of distributed neural networks in which the prefrontal cortex (PFC) is central. The present study used fNIRS to examine how PFC is recruited to support cognitive control in 5–6 and 8-9-year-old children, by (a) progressively increasing cognitive control demands within the same task, and (b) manipulating the social context in which the task was performed (neutral, cooperative, or competitive), a factor that has been shown to influence cognitive control. Activation increased more in left than right PFC with cognitive control demands, a pattern which was more pronounced in older than younger children. In addition, activation was higher in left PFC in competitive than cooperative contexts, and higher in right PFC in cooperative and neutral than competitive contexts. These findings suggest that increasingly efficient cognitive control during childhood is supported by more differentiated recruitment of PFC as a function of cognitive control demands with age.

Executive Control and Adolescent Health: Toward A Conceptual Framework

Executive control is a set of cognitive abilities that may impact a variety of adolescent health behaviors and outcomes; however, research on executive control as a contributor to the physical health of youth is relatively limited. Therefore, the current article explores the possible role of executive control in adolescent health by reviewing relevant literature and proposing a conceptual framework to guide future research in this area. The development of executive control from preschool through adolescence is described, with particular attention to executive control in the unique health context of adolescence. A new conceptual model is proposed, focusing on how executive control may play a critical role in supporting health in adolescence and beyond through the mechanisms of attentional, behavioral, and emotional control. Literature exploring associations between youth executive control and key health behaviors (including diet, physical activity, sleep and substance use) is reviewed. Researchers and clinicians are encouraged to consider executive control as an important cross-cutting contributor to health during adolescence and beyond and to incorporate this construct into longitudinal studies of health.

Socioeconomic disparity in prefrontal development during early childhood

Socioeconomic status (SES) has a powerful influence on cognitive, social and brain development. Children from low-SES backgrounds show poor executive function (EF). However, it is unclear if there is a SES-dependent disparity in functional brain development. The present study examined whether the SES of preschool children (N = 93) is associated with prefrontal activation during cognitive shifting tasks as measured by near-infrared spectroscopy. Low-SES children did not show activation in lateral prefrontal regions during the tasks, whereas middle- and high-SES children showed prefrontal activations, although no differences were found in terms of behavioural performance. These results suggest that SES can affect the functional development of the prefrontal regions. In this study, we discuss the practical implications of the results.

Visual foraging and executive functions: A developmental perspective

Visual foraging tasks, where participants search for multiple targets at a time, may provide a richer picture of visual attention than traditional single-target visual search tasks. To contribute to the mapping of foraging abilities throughout childhood and to assess whether foraging ability is dependent upon EF abilities, we compared the foraging of 66 children aged 4-7 years (mean age = 5.68 years, SD = 0.97 years, 33 girls), 67 children aged 11-12 years (mean age = 11.80 years, SD = 0.30 years; 36 girls), and 31 adults aged 20-37 (mean age 30.32 years, SD 4.37 years, 18 females) in Iceland, with a task involving multiple targets of different types. We also measured three subdomains of executive functions; inhibition, attentional flexibility, and working memory. Our results show that foraging improves dramatically between the preschool and middle school years, with the older children showing similar foraging abilities as adults due to greater ease of switching between target types. The older children and adults randomly switch between target templates during feature foraging, but exhaustively forage for a single target type before switching during conjunction foraging. Younger children, conversely, tended to also stick to the same target type for long runs during feature foraging, showing that they have difficulties with feature-based tasks. Switch costs were much lower for the older children than the youngest age group, and on par with those of adults, resulting in fast and efficient foraging. Lastly, we found a connection between foraging ability and both working memory and attentional flexibility, but not inhibition. Our study shows that foraging is a promising way of studying visual attention, how it changes throughout the lifespan, and how it is connected to other cognitive functions.