Evidence for a mechanistic model of cognitive control

Neurocognitive performance of badminton players at different competitive levels in visuospatial attention tasks

Visuospatial attention (VSA) is a cognitive function that enables athletes, particularly those engaged in open-skill sports, to allocate attentional resources efficiently to the appropriate target and in the appropriate direction. Studies have indicated that expert players exhibit superior cognitive performance to that of novices. However, no study has investigated differences in VSA performance among elite, expert, and intermediate badminton players or the potential neurophysiological mechanisms underlying such differences. Accordingly, the present study explored neuropsychological and neurophysiological parameters during VSA tasks among badminton players of varying competitive levels. The study included 54 participants and divided them into three groups according to their competition records: elite (n = 18), expert (n = 18), and intermediate (n = 18). Their neuropsychological performance and brain event-related potentials (ERPs) during the Posner cueing paradigm were collected. Although the three groups did not differ in their accuracy rates, ERP N2 amplitudes, or N2 or P3 latencies, the elite and expert groups exhibited notably faster reaction times and more pronounced P3 amplitudes than did the intermediate group during the cognitive task. However, we did not observe these between-group differences when we controlled for the covariate training years. Additionally, the elite and expert groups exhibited comparable neurocognitive performance. These findings indicate that badminton players' competitive levels influence their VSA. However, the beneficial effects on neuropsychological and neurophysiological performance could stabilize after a certain level of badminton competence is reached. Year of training could also be a major factor influencing badminton players' neurocognitive performance in VSA tasks.

Out-of-phase transcranial alternating current stimulation modulates the neurodynamics of inhibitory control

Transcranial alternating current stimulation (tACS) is an efficient neuromodulation technique that enhances cognitive function in a non-invasive manner. Using functional magnetic resonance imaging, we investigated whether tACS with different phase lags (0° and 180°) between the dorsal anterior cingulate and left dorsolateral prefrontal cortices modulated inhibitory control performance during the Stroop task. We found out-of-phase tACS mediated improvements in task performance, which was neurodynamically reflected as putamen, dorsolateral prefrontal, and primary motor cortical activation as well as prefrontal-based top-down functional connectivity. Our observations uncover the neurophysiological bases of tACS-phase-dependent neuromodulation and provide a feasible non-invasive approach to effectively modulate inhibitory control.

An immersive virtual reality tool for assessing left and right unilateral spatial neglect

The reported rate of the occurrence of unilateral spatial neglect (USN) is highly variable likely due to the lack of validity and low sensitivity of classical tools used to assess it. Virtual reality (VR) assessments try to overcome these limitations by proposing immersive and complex environments. Nevertheless, existing VR-based tasks are mostly focused only on near space and lack analysis of psychometric properties and/or clinical validation. The present study evaluates the clinical validity and sensitivity of a new immersive VR-based task to assess USN in the extra-personal space and examines the neuronal correlates of deficits of far space exploration. The task was administrated to two groups of patients with right (N = 28) or left (N = 11) hemispheric brain lesions, also undergoing classical paper-and-pencil assessment, as well as a group of healthy participants. Our VR-based task detected 44% of neglect cases compared to 31% by paper-and-pencil tests in the total sample. Importantly, 30% of the patients (with right or left brain lesions) with no clear sign of USN on the paper-and-pencil tests performed outside the normal range in the VR-based task. Voxel lesion-symptom mapping revealed that deficits detected in VR were associated with lesions in insular and temporal cortex, part of the neural network involved in spatial processing. These results show that our immersive VR-based task is efficient and sensitive in detecting mild to strong manifestations of USN affecting the extra-personal space, which may be undetected using standard tools.

Machine Learning Based on Event-Related EEG of Sustained Attention Differentiates Adults with Chronic High-Altitude Exposure from Healthy Controls

(1) Objective: The aim of this study was to examine the effect of high altitude on inhibitory control processes that underlie sustained attention in the neural correlates of EEG data, and explore whether the EEG data reflecting inhibitory control contain valuable information to classify high-altitude chronic hypoxia and plain controls. (2) Methods: 35 chronic high-altitude hypoxic adults and 32 matched controls were recruited. They were required to perform the go/no-go sustained attention task (GSAT) using event-related potentials. Three machine learning algorithms, namely a support vector machine (SVM), logistic regression (LR), and a decision tree (DT), were trained based on the related ERP components and neural oscillations to build a dichotomous classification model. (3) Results: Behaviorally, we found that the high altitude (HA) group had lower omission error rates during all observation periods than the low altitude (LA) group. Meanwhile, the ERP results showed that the HA participants had significantly shorter latency than the LAs for sustained potential (SP), indicating vigilance to response-related conflict. Meanwhile, event-related spectral perturbation (ERSP) analysis suggested that lowlander immigrants exposed to high altitudes may have compensatory activated prefrontal cortexes (PFC), as reflected by slow alpha, beta, and theta frequency-band neural oscillations. Finally, the machine learning results showed that the SVM achieved the optimal classification F1 score in the later stage of sustained attention, with an F1 score of 0.93, accuracy of 92.54%, sensitivity of 91.43%, specificity of 93.75%, and area under ROC curve (AUC) of 0.97. The results proved that SVM classification algorithms could be applied to identify chronic high-altitude hypoxia. (4) Conclusions: Compared with other methods, the SVM leads to a good overall performance that increases with the time spent on task, illustrating that the ERPs and neural oscillations may provide neuroelectrophysiological markers for identifying chronic plateau hypoxia.

Inconsistencies between Subjective Reports of Cognitive Difficulties and Performance on Cognitive Tests are Associated with Elevated Internalising and Externalising Symptoms in Children with Learning-related Problems

Children with learning difficulties are commonly assumed to have underlying cognitive deficits by health and educational professionals. However, not all children referred for psycho-educational assessment will be found to have deficits when their abilities are measured by performance on cognitive tasks. The primary aim of this study was to estimate the prevalence of this inconsistent cognitive profile (ICP) in a transdiagnostic sample of children referred by health and education service providers for problems related to attention, learning and memory (N = 715). A second aim was to explore whether elevated mental health problems were associated with ICPs. Findings suggest that approximately half of this sample could be characterised as having an ICP. Cognitive difficulties, whether identified by parent ratings or task performance, were associated with elevated internalising and externalising difficulties. Crucially, a larger discrepancy between a parent's actual ratings of a child's cognitive difficulties and the ratings that would be predicted based on the child's performance on cognitive tasks was associated greater internalising and externalising difficulties for measures of working memory, and greater externalising difficulties for measures of attention. These findings suggest that subjective cognitive difficulties occurring in the absence of any task-based performance deficits may be a functional problem arising from mental health problems.

Changes in the TMS-evoked potential N100 in the dorsolateral prefrontal cortex as a function of depression severity in adolescents

Studies using transcranial magnetic stimulation with simultaneous electroencephalography (TMS-EEG) revealed an imbalance between cortical excitation and inhibition (E/I) in the dorsolateral prefrontal cortex (DLPFC) in depression. As adolescence is a developmental period with an increase in depression prevalence and profound neural changes, it is crucial to study the relationship between depression and cortical excitability in adolescence. We aimed to investigate the cortical excitability of the DLPFC in adolescents with depression and a dependency of the TMS-evoked potential N100 on the depression severity. 36 clinical patients (12–18 years of age; 21 females) with a major depressive episode were assessed twice in a longitudinal design: shortly after admission (T0) and after six weeks of intervention (T1). GABA-B-mediated cortical inhibition in the left and right DLPFC, as assessed by the N100, was recorded with EEG. Significantly higher depression scores were reported at T0 compared to T1 (p < 0.001). N100 amplitudes were significantly increased (i.e., more negative) at T0 compared to T1 (p = 0.03). No significant hemispheric difference was found in the N100 component. The correlation between the difference in depression severity and the difference in N100 amplitudes (T0–T1) obtained during stimulation of the left DLPFC did not remain significant after correction for testing in both hemispheres. Higher N100 amplitudes during a state of greater depression severity are suggestive of an E/I imbalance in the DLPFC in adolescents with an acute depressive episode. The N100 reduction potentially reflects a normalization of DLPFC over inhibition in association with decreased depressive symptomatology, indicating severity dependency.

Go/no-go task performance of Japanese children: Differences by sex, grade, and lifestyle habits

Background

Japanese children face critical psychological challenges that urgently need to be addressed.

Objective

This study aimed to clarify performance differences in go/no-go tasks among Japanese elementary and junior high students by sex and grade and comprehensively investigate the relationship between children's lifestyle habits and performance.

Methods

In total, 4,482 (2,289 males, 2,193 females) 1st grade elementary to 3rd grade junior high students (6-15 years old) participated. We conducted a survey and the go/no-go experiments in the participating schools on weekday mornings from November 2017 to February 2020. We collected data on the number of errors in the go/no-go tasks in response to visual stimuli (commission errors in the no-go tasks; omission errors in the go tasks); and on lifestyle habits (i.e., sleep, screen time, and physical activity) using questionnaires.

Results

For the commission errors, the results demonstrated differences by sex and grade; for the omission errors, differences were only observed by grade. Additionally, we analysed the relationship between both types of errors and sex, grade, sleep conditions, screen time, and physical activity using binomial logistic regression analysis. Commission errors were significantly related to sex and grade whereas omission errors were related to grade, bedtime, screen time, and physical activity.

Conclusions

Our results highlighted that children's cognitive functions are related to their lifestyle habits (i.e., sleep conditions, screen time, and physical activity) in addition to sex and grade.

Measuring the Impact of Bilingualism on Executive Functioning Via Inhibitory Control Abilities in Autistic Children

One factor that may influence how executive functions develop is exposure to more than one language in childhood. This study explored the impact of bilingualism on inhibitory control in autistic (n = 38) and non-autistic children (n = 51). Bilingualism was measured on a continuum of exposure to investigate the effects of language environment on two facets of inhibitory control. Behavioural control of motor impulses was modulated positively through increased bilingual exposure, irrespective of diagnostic status, but bilingual exposure did not significantly affect inhibition involving visual attention. The results partially support the hypothesis that bilingual exposure differentially affects components of inhibitory control and provides important evidence for families that bilingualism is not detrimental to their development.

Adolescent health series: Adolescent neurocognitive development in Western and Sub-Saharan African contexts

The transitional period of adolescence has long been associated with physical, social and behavioural change. During this time, adolescents start to develop their own self-identity, make important life decisions and acquire the necessary skills to successfully transition to adulthood. More recently, advances in brain imaging technology have enabled increased understanding of structural and functional changes in the human brain during this developmental period, and how they relate to social, emotional, motivational and cognitive development. The ability to integrate these developing cognitive processes in increasingly complex social contexts is a key aspect of mature decision-making, which has implications for adolescent health, educational, economic and social outcomes. Insights from the field of developmental cognitive neuroscience could increase our understanding of this influential stage of life and thus inform potential interventions to promote adolescent health, a critical goal for global health research. Many social changes occur during adolescence and the social environment shapes both brain and cognitive development and the decisions adolescents make. Thus, it is important to study adolescent neurocognitive development in socio-cultural context. Yet, despite evidence from Western studies that socio-cultural and economic factors impact on adolescent neurocognitive development, existing studies of adolescent neurocognitive development in sub-Saharan Africa are relatively scarce. We summarise research findings from Western and sub-Saharan African contexts and highlight areas where research is lacking. Longitudinal studies from more diverse global samples will be needed to build a comprehensive model of adolescent development, that characterises both commonalities in developmental trajectories, as well as the way these can meaningfully differ between both individuals and contexts.

The impact of preterm birth on the executive functioning of preschool children: A systematic review

This paper presents a systematic review of the impact of preterm childbirth on the later executive functioning of preschool-aged children. A systematic search for studies published between 2014 and 2019 was performed using the following keywords: executive funct* AND preterm AND child. The methodological quality of the reports was examined using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement. Thirty-two studies were reviewed and scored at least 67% on the methodological quality assessment. In comparison to children born full-term, preschool children born preterm exhibit executive functioning deficits in the dimensions of the global index, inhibitory control, cognitive flexibility, working memory, and planning/executive functioning. These findings are independent of the degree of prematurity at birth. Since executive functioning has many complex components, future studies should assess the dimensions of executive functioning separately in preschool-aged children born preterm, rather than as a single measure.

Emotion information processing as a new component of emotional intelligence: Theoretical framework and empirical evidence

The relationship between emotional intelligence (EI) and emotion information processing (EIP) has received surprisingly little attention in the literature. The present research addresses these gaps in the literature by introducing a conceptualization of emotional intelligence as composed of two distinct components: (1) EIK or emotion Knowledge component, captured by current ability emotional intelligence tests, related to top-down, higher order reasoning about emotions, and which depends more strongly on acquired and culture-bound knowledge about emotions; (2) EIP or emotion information Processing component, measured with emotion information processing tasks, requires faster processing and is based on bottom-up attention-related responses to emotion information. In Study 1 ( N = 349) we tested the factorial structure of this new EIP component within the nomological network of intelligence and current ability emotional intelligence. In Study 2 ( N =111) we tested the incremental validity of EIP in predicting both overall performance and the charisma of a presenter while presenting in a stressful situation. Results support the importance of acknowledging the role of emotion information processing in the emotional intelligence literature and point to the utility of introducing a new EI measure that would capture stable individual differences in how individuals process emotion information.

Effortful Control - A Transdiagnostic Dimension Underlying Internalizing and Externalizing Psychopathology

Effortful control (EC) or self-regulation refers to the ability to regulate behavior, emotion, and cognition. It has been identified as a contributor to both adaptive and adverse outcomes in children, adolescents, and adults and this across many domains. As such, it could be considered as a transdiagnostic dimension underlying internalizing (e.g., mood and anxiety disorders) and externalizing (e.g., substance use disorders, ADHD) psychopathology. We aimed to examine the role of EC throughout the adult psychopathological spectrum by means of a literature search of studies published between 2008 and 2018. Overall, the results point to the role of EC in the development of a broad spectrum of psychiatric diagnosis, reflecting the transdiagnostic characteristic of this construct. This role may be both directly causal or as a mediator factor influencing outcomes of a specific disorder. Early assessment of EC and early interventions to improve EC might help to avoid or decrease the risk of developing psychopathology.

Processes linking socioeconomic disadvantage and neural correlates of cognitive control in adolescence

Socioeconomic status (SES) is broadly associated with self-regulatory abilities across childhood and adolescence. However, there is limited understanding of the mechanisms underlying this association, especially during adolescence when individuals are particularly sensitive to environmental influences. The current study tested perceived stress, household chaos, parent cognitive control, and parent-adolescent relationship quality as potential proximal mediators of the association between family SES and neural correlates of cognitive control. A sample of 167 adolescents and their primary caregivers participated in a longitudinal study across four years. SES was indexed by caregivers' education and income-to-needs ratio at Time 1. At Time 2, adolescents reported on their perceived stress, household chaos, and relationship with parents, and parents completed a cognitive control task. Two years later, adolescents completed the same cognitive control task while blood-oxygenation-level-dependent (BOLD) response was monitored with functional magnetic resonance imaging (fMRI). A parallel mediation model indicated that parent cognitive control, but not other proximal factors, explained the relation between SES and adolescents' activation in the middle frontal gyrus during a cognitive control task. The results suggest potential targets for intervention and prevention efforts that may positively alter neurocognitive outcomes related to socioeconomic disadvantage.

Inhibitory control in trauma-exposed youth: A systematic review

The aim of this systematic review was to provide insight in inhibitory control (prepotent response inhibition and interference control) in trauma-exposed youth from a developmental perspective and exploring the effects of prolonged stress. A systematic search was conducted, resulting in 1722 abstracts. Of those, 33 studies met inclusion criteria. Twelve studies measured prepotent response inhibition (Go/no-go and Stop-signal task), 20 studies measured interference control (Flanker and Stroop task), and one measured both. Some studies indeed found evidence for prolonged trauma exposure impeding both subcomponents of inhibitory control, although others did not. At a later age, inhibitory control problems on task performance seem to disappear. However, distinct patterns of brain activity may suggest that those individuals employ compensation strategies. Together, the findings may suggest that non-specific inhibitory control problems occur after prolonged trauma exposure, with older youth possibly employing compensation strategies on the tasks. Future studies may provide a clearer picture of the compensation strategies and the circumstances in which they become visible.

Effects of theta burst stimulation over the dorsolateral prefrontal cortex on language switching - A behavioral and ERP study

This study investigated the role of the left dorsolateral prefrontal cortex (DLPFC) in language switching using theta burst stimulation (TBS) and electroencephalography in late bilinguals. After a sham-controlled baseline, participants received either excitatory or inhibitory TBS over the left DLPFC before conducting picture naming tasks in pure language blocks and a language switching block, as well as a nonverbal switching task. On the behavioral level, we found no effect of TBS. However, the ERP-analysis revealed an effect of Stimulation for the picture naming tasks, characterized by alterations in the left DLPFC at 20-72 ms, and in networks associated with conflict resolution and self-monitoring at 533-600 ms. As we did not find an interaction between Stimulation and Block (switching vs non-switching), prefrontal stimulation did not specifically modulate interlanguage control. The left DLPFC might rather be involved in enhancingmaintenance of task demands and self-monitoring during language production in both mono- and bilingual contexts.

Sex differences in the association between exposure to indoor particulate matter and cognitive control among children (age 6-14 years) living near coal-fired power plants

Coal fly ash consists of inhalable particulate matter with varying concentrations of neurotoxic metals. Children living near coal-fired power plants with coal fly ash storage facilities may be exposed to coal fly ash when it escapes as fugitive dust emissions into surrounding communities. Previous research on outdoor particulate matter air pollution of similar aerodynamic diameter (PM₁₀) suggests exposure may be associated with impaired cognitive control. The purpose of this research was to investigate sex-differences in the association between exposure to indoor PM₁₀ and cognitive control among children (n = 221), ages 6-14 years, living near coal-fired power plants with fly ash storage facilities. In an ongoing community-based study, we measured indoor PM₁₀ concentrations in participants' housing units and used performance measures from the BARS (Behavior Assessment and Research System) Continuous Performance Test (CPT) and Selective Attention Test (SAT) to assess neurotoxic effects on cognitive control. In adjusted negative binomial regression models, we found children living in housing units with higher indoor PM₁₀ concentrations had a higher risk of commission errors on the CPT (incidence rate ratio (IRR) = 1.22 per interquartile range difference (IQR = 0.72 μg/m³) in natural log-transformed PM₁₀ concentrations; 95% CI = 1.01, 1.46) and SAT (IRR = 1.14; 95% CI = 1.01, 1.28). Furthermore, child sex modified the association between PM₁₀ concentration and CPT commission errors. Among females, higher PM₁₀ concentration was associated with higher risk of CPT commission errors (IRR = 1.39; 95% CI = 1.06, 1.82), but we found no association among males (IRR = 1.01; 95% CI = 0.79, 1.30). We found no association between PM₁₀ concentrations and CPT or SAT response latency. Our results suggest females living near coal-fired plants with coal fly ash storage facilities may be more susceptible to impaired cognitive control associated with particulate matter exposure. Children living near coal-fired power plants with coal fly ash storage facilities who are exposed to particulate matter may have an increased risk of impulse control problems.

Brains of a feather flocking together? Peer and individual neurobehavioral risks for substance use across adolescence

Adolescence is a period of heightened susceptibility to peer influences, and deviant peer affiliation has well-established implications for the development of psychopathology. However, little is known about the role of brain functions in pathways connecting peer contexts and health risk behaviors. We tested developmental cascade models to evaluate contributions of adolescent risk taking, peer influences, and neurobehavioral variables of risk processing and cognitive control to substance use among 167 adolescents who were assessed annually for four years. Risk taking at Time 1 was related to substance use at Time 4 indirectly through peer substance use at Time 2 and insular activation during risk processing at Time 3. Furthermore, neural cognitive control moderated these effects. Greater insular activation during risk processing was related to higher substance use for those with greater medial prefrontal cortex activation during cognitive control, but it was related to lower substance use among those with lower medial prefrontal cortex activation during cognitive control. Neural processes related to risk processing and cognitive control play a crucial role in the processes linking risk taking, peer substance use, and adolescents' own substance use.

Visuospatial Attention and Saccadic Inhibitory Control in Children With Cerebral Palsy

Cerebral palsy (CP) is a non-progressive syndrome due to a pre-, peri- or post-natal brain injury, which frequently involves an impairment of non-motor abilities. The aim of this article was to examine visuospatial attention and inhibitory control of prepotent motor responses in children with CP showing a normal IQ or mild cognitive impairment, measuring their performance in oculomotor tasks. Ten children (9–16-year-old) with spastic CP and 13 age-matched, typically developing children (TDC) participated in the study. Subjects performed a simple visually-guided saccade task and a cue-target task, in which they performed a saccade towards a peripheral target, after a non-informative visual cue was flashed 150 ms before the imperative target, either at the same (valid) or at a different (invalid) spatial position. Children with CP showed severe executive deficits in maintaining sustained attention and complying with task instructions. Furthermore, saccadic inhibitory control appeared to be significantly impaired in the presence of both stimulus-driven and goal-directed captures of attention. In fact, patients showed great difficulties in suppressing saccades not only to the cue stimuli but also to the always-present target placeholders, which represented powerful attentional attractors that had to be covertly attended throughout the task execution. Moreover, impairment did not affect in equal manner the whole visual field but showed a marked spatial selectivity in each individual subject. Saccade latencies in the cue-target task were faster in the valid than in the invalid condition in both child groups, indicating the preservation of low-level visuospatial attentive capabilities. Finally, this study provides evidence that these impairments of executive skills and in inhibitory control, following early brain injuries, manifest in childhood but recover to virtually normal level during adolescence.

Adolescent cognitive control, theta oscillations, and social observation

Theta oscillations (4-8 Hz) provide an organizing principle of cognitive control, allowing goal-directed behavior. In adults, theta power over medial-frontal cortex (MFC) underlies conflict/error monitoring, whereas theta connectivity between MFC and lateral-frontal regions reflects cognitive control recruitment. However, prior work has not separated theta responses that occur before and immediately after a motor response, nor explained how medial-lateral connectivity drives different kinds of control behaviors. Theta's role during adolescence, a developmental window characterized by a motivation-control mismatch also remains unclear. As social observation is known to influence motivation, this might be a particularly important context for studying adolescent theta dynamics. Here, adolescents performed a flanker task alone or under social observation. Focusing first on the nonsocial context, we parsed cognitive control into dissociable subprocesses, illustrating how theta indexes distinct components of cognitive control working together dynamically to produce goal-directed behavior. We separated theta power immediately before/after motor responses, identifying behavioral links to conflict monitoring and error monitoring, respectively. MFC connectivity was separated before/after responses and behaviorally-linked to reactive and proactive control, respectively. Finally, distinct forms of post-error control were dissociated, based on connectivity with rostral/caudal frontal cortex. Social observation was found to exclusively upregulate theta measures indexing post-response error monitoring and proactive control, as opposed to conflict monitoring and reactive control. Linking adolescent cognitive control to theta oscillations provides a bridge between non-invasive recordings in humans and mechanistic studies of neural oscillations in animal models; links to social observation provide insight into the motivation-control interactions that occur during adolescence.

Commonality between executive functioning and effortful control related to adjustment

This study examined the association between executive functioning (EF) and effortful control (EC), and tested whether cognitive control as the commonality of EF and EC, predicted competence and internalizing and externalizing symptomatology in children (N = 218, 6-8 years) and adolescents (N = 157, 13-14 years). Confirmatory factor analyses suggested cognitive control-inhibitory control and attentional control-as a significant overlap between EF and EC. Structural equation modeling analyses indicated that the cognitive control latent factor was associated with competence and internalizing and externalizing symptomatology among children and externalizing symptomatology among adolescents. The results provide evidence that inhibitory control and attentional control are the commonality between EF and EC and highlight that they are linked with positive and negative adjustment outcomes.

Neural cognitive control moderates the association between insular risk processing and risk-taking behaviors via perceived stress in adolescents

Adolescence is a critical period for the initiation of risk-taking behaviors. We examined the longitudinal interplay between neural correlates of risk processing and cognitive control in predicting risk-taking behaviors via stress. The sample consisted of 167 adolescents (53% males) who were assessed twice (MAgeTime1 = 14.13, MAgeTime2 = 15.05). Neural risk processing was operationalized as blood-oxygen-level-dependent (BOLD) responses in the anterior insula during a lottery choice task and neural cognitive control as BOLD responses during an inhibitory control task. Adolescents reported on perceived stress and risk-taking behaviors. Structural equation modeling analyses indicated that low insular risk processing predicted increases in perceived stress, while perceived stress did not predict changes in insular risk processing across one year. Moreover, significant moderation by neural cognitive control indicated that low insular risk processing predicted increases in risk-taking behaviors via increases in perceived stress among adolescents with poor neural cognitive control, but not among adolescents with good neural cognitive control. The results suggest that risk processing in the anterior insular cortex plays an important role in stress experience and risk-taking behaviors particularly for vulnerable adolescents with poor neural cognitive control.

An EEG coherence-based analysis approach for investigating response conflict processes in 7 and 9-year old children

Understanding the development of the brain's neural networks can reveal critical insights into the cognitive changes that occur from infancy to late childhood. Behavioural metrics including: task accuracy, stimuli recognition, and reaction time show dramatic changes over childhood. In this study we investigated response control using the Erikson Flanker task. In a dataset of 45 EEG recordings, we calculated spectral coherence to measure connectivity between all possible electrode pairs. Coherence measures were performed on two different trial conditions -congruent (where there is no response conflict) and incongruent (where response conflict is induced). The increase in incongruent coherence compared to the congruent was investigated for each electrode pair over 45 healthy subjects aged seven years. The same calculation was then performed on the same group of subjects two years later when they were aged nine years. The results revealed that at age seven years, increased coherence was detected in the left prefrontal to right and left parieto-occipital - i.e. an anatomical region located between the parietal and occipital lobes - within theta band. No increase was found for the older group-at age nine years- which may indicate cognitive development in conflict processing mechanism.

Semantic interference and its control: A functional neuroimaging and connectivity study

During picture naming, the ease with which humans generate words is dependent upon the context in which they are named. For instances, naming previously presented items results in facilitation. Instead, naming a picture semantically related to previous items displays persistent interference effects (i.e., cumulative semantic interference, CSI). The neural correlates of CSI are still unclear and it is a matter of debate whether semantic control, or cognitive control more in general, is necessary for the resolution of CSI. We carried out an event-related fMRI experiment to assess the neural underpinnings of the CSI effect and the involvement and nature of semantic control. Both left inferior frontal gyrus (LIFG) and the left caudate nucleus (LCN) showed a linear increase of BOLD response positively associated with the consecutive number of presentations of semantically related pictures independently of task-load. The generalized psychophysiological interaction analysis showed that LIFG demonstrated a quantitative neural connectivity difference with the left supramarginal and angular gyri for increases of task-load and with the fusiform gyri for linear CSI increases. Furthermore, seed-to-voxel functional connectivity showed that LIFG activity coupled with different regions involved in cognitive control and lexicosemantic processing when semantic interference was elicited to a minimum or maximum degree. Our results are consistent with the lexical-competitive nature of the CSI effect, and we provide novel evidence that semantic control lies upon a more general cognitive control network (i.e., LIFG and LCN) responsible for resolving interference between competing semantically related items through connectivity with different brain areas in order to guarantee the correct response. Hum Brain Mapp 37:4179-4196, 2016. © 2016 Wiley Periodicals, Inc.

Executive functioning and substance use in adolescence: Neurobiological and behavioral perspectives

The current review is guided by the theoretical perspective that emphasizes the regulating role of executive functioning (Carver et al., 2009) and presents studies that elucidate the ways that executive functioning (inhibition and working memory) explain individual differences in adolescent substance use independently or by regulating the reactive system (reward and punishment sensitivity). Behavioral studies indicate that main effects of executive functioning on adolescent substance use are often nonsignificant or weak in effect sizes. In contrast, emerging evidence suggests consistent and stronger regulating effects of executive functioning over reward and punishment sensitivity. Functional neuroimaging studies reveal significant associations between executive functioning task-related hemodynamic responses and substance use with strong effect sizes. There is also direct evidence from studies testing statistical interactions of the regulating effects of EF-related brain activation, and indirect evidence in studies examining functional connectivity, temporal discounting, and reinforced control. We note key future directions and ways to address limitations in existing work.

Executive function in children born preterm: Risk factors and implications for outcome

Executive function (EF) refers to the set of cognitive processes involved in the self-regulation of emotion and goal-directed behavior. These skills and the brain systems that support them develop throughout childhood and are frequently compromised in preterm children, even in those with broadly average global cognitive ability. Risks for deficits in EF in preterm children and attendant problems in learning and psychosocial functioning are higher in those with more extreme prematurity, neonatal complications, and related brain abnormalities. Associations of higher levels of EF with more supportive home and school environments suggest a potential for attenuating these risks, especially with early identification. Further research is needed to understand how deficits in EF evolve in preterm children, refine assessment methods, and develop interventions that either promote the development of EF in this population or help children to compensate for these weaknesses.

The development of social cognition in adolescence: An integrated perspective

Social cognitive processes are critical in navigating complex social interactions and are associated with a network of brain areas termed the 'social brain'. Here, we describe the development of social cognition, and the structural and functional changes in the social brain during adolescence, a period of life characterised by extensive changes in social behaviour and environments. Neuroimaging and behavioural studies have demonstrated that the social brain and social cognition undergo significant development in human adolescence. Development of social cognition and the social brain are discussed in the context of developments in other neural systems, such as those implicated in motivational-affective and cognitive control processes. Successful transition to adulthood requires the rapid refinement and integration of these processes and many adolescent-typical behaviours, such as peer influence and sensitivity to social exclusion, involve dynamic interactions between these systems. Considering these interactions, and how they vary between individuals and across development, could increase our understanding of adolescent brain and behavioural development.

Reach tracking reveals dissociable processes underlying cognitive control

The current study uses reach tracking to investigate how cognitive control is implemented during online performance of the Stroop task (Experiment 1) and the Eriksen flanker task (Experiment 2). We demonstrate that two of the measures afforded by reach tracking, initiation time and reach curvature, capture distinct patterns of effects that have been linked to dissociable processes underlying cognitive control in electrophysiology and functional neuroimaging research. Our results suggest that initiation time reflects a response threshold adjustment process involving the inhibition of motor output, while reach curvature reflects the degree of co-activation between response alternatives registered by a monitoring process over the course of a trial. In addition to shedding new light on fundamental questions concerning how these processes contribute to the cognitive control of behavior, these results present a framework for future research to investigate how these processes function across different tasks, develop across the lifespan, and differ among individuals.

Intentional and automatic numerical processing as predictors of mathematical abilities in primary school children

Previous studies have suggested that numerical processing relates to mathematical performance, but it seems that such relationship is more evident for intentional than for automatic numerical processing. In the present study we assessed the relationship between the two types of numerical processing and specific mathematical abilities in a sample of 109 children in grades 1-6. Participants were tested in an ample range of mathematical tests and also performed both a numerical and a size comparison task. The results showed that numerical processing related to mathematical performance only when inhibitory control was involved in the comparison tasks. Concretely, we found that intentional numerical processing, as indexed by the numerical distance effect in the numerical comparison task, was related to mathematical reasoning skills only when the task-irrelevant dimension (the physical size) was incongruent; whereas automatic numerical processing, indexed by the congruency effect in the size comparison task, was related to mathematical calculation skills only when digits were separated by small distance. The observed double dissociation highlights the relevance of both intentional and automatic numerical processing in mathematical skills, but when inhibitory control is also involved.

Brain bases of language selection: MEG evidence from Arabic-English bilingual language production

Much of the world's population is bilingual, hence, language selection is a core component of language processing in a significant proportion of individuals. Though language selection has been investigated using artificial cues to language choice such as color, little is known about more ecologically valid cues. We examined with MEG the neurophysiological and behavioral effects of two natural cues: script and cultural context, hypothesizing the former to trigger more automatic language selection. Twenty Arabic-English bilinguals performed a number-naming task with a Match condition, where the cue and target language of response matched, and a Mismatch condition, with opposite instruction. The latter addressed the mechanisms responsible for overriding natural cue-language associations. Early visual responses patterned according to predictions from prior object recognition literature, while at 150–300 ms, the anterior cingulate cortex showed robust sensitivity to cue-type, with enhanced amplitudes to culture trials. In contrast, a mismatch effect for both cue-types was observed at 300–400 ms in the left inferior prefrontal cortex. Our findings provide the first characterization of the spatio-temporal profile of naturally cued language selection and demonstrate that natural but less automatic language-choice, elicited by cultural cues, does not engage the same mechanisms as the clearly unnatural language-choice of our mismatch tasks.

Regional brain glucose metabolism and neurocognitive function in adult survivors of childhood cancer treated with cranial radiation

The objective of this study was to examine associations between regional brain metabolism, as measured by (18)F-FDG PET, and neurocognitive outcomes in adult survivors of childhood acute lymphoblastic leukemia (ALL) treated with cranial radiation.

METHOD

Thirty-eight adult survivors of ALL were randomly selected from a large cohort treated with cranial radiation therapy (19 with 18 Gy and 19 with 24 Gy of exposure). At a mean age of 26.4 (range, 22.3-37.4) years, and 23.5 (range, 20.4-32.8) years since diagnosis, patients underwent comprehensive neurocognitive evaluations and brain (18)F-FDG PET imaging during a resting condition. (18)F-FDG PET images were analyzed stereotactically, and pixel values were normalized to global activity. Predefined region-of-interest and voxel-based correlation analyses were performed.

RESULTS

Compared with national norms, survivors demonstrated lower vocabulary (P < 0.001), reading (P < 0.001), mathematics (P < 0.001), working memory (P < 0.001), oral naming speed (P < 0.001), and cognitive flexibility (P < 0.001). Metabolic activity was higher in basal gangliar structures for those treated with 24 Gy of cranial radiation therapy (P = 0.04). Metabolic activity was positively correlated with oral naming speed in both lateral frontal lobes (ρ = 0.48 and 0.47 for right and left frontal regions, respectively, P < 0.01) and negatively correlated with cognitive flexibility in the sections of the basal ganglia (P < 0.01 for both caudate and putamen).

CONCLUSION

Neurocognitive impairment in long-term survivors of ALL treated with cranial radiation appears to be associated with increased metabolic activity in frontal cerebral cortical and subcortical regions in the basal ganglia, suggesting decreased efficiency of the frontostriatal brain circuit.

Dissociable patterns in the control of emotional interference in adults with attention-deficit/hyperactivity disorder (ADHD) and in adults with alcohol dependence

Objectives

To effectively manage current task demands, attention must be focused on task-relevant information while task-irrelevant information is rejected. However, in everyday life, people must cope with emotions, which may interfere with actual task demands and may challenge functional attention allocation. Control of interfering emotions has been associated with the proper functioning of the dorsolateral prefrontal cortex (DLPFC). As DLPFC dysfunction is evident in subjects with ADHD and in subjects with alcohol dependence, the current study sought to examine the bottom-up effect of emotional distraction on task performance in both disorders.

Methods

Male adults with ADHD (n = 22), male adults with alcohol dependence (n = 16), and healthy controls (n = 30) performed an emotional working memory task (n-back task). In the background of the task, we presented neutral and negative stimuli that varied in emotional saliency.

Results

In both clinical groups, a working memory deficit was evident. Moreover, both clinical groups displayed deficient emotional interference control. The n-back performance of the controls was not affected by the emotional distractors, whereas that of subjects with ADHD deteriorated in the presence of low salient distractors, and that of alcoholics did not deteriorate until high salient distractors were presented. Subsequent to task performance, subjects with ADHD accurately recognized more distractors than did alcoholics and controls. In alcoholics, picture recognition accuracy was negatively associated with n-back performance, suggesting a functional association between the ability to suppress emotional distractors and successful task performance. In subjects with ADHD, performance accuracy was negatively associated with ADHD inattentive symptoms, suggesting that inattention contributes to the performance deficit.

Conclusions

Subjects with ADHD and alcoholics both display an emotional interference control deficit, which is especially pronounced in subjects with ADHD. Beyond dysfunctional attention allocation processes, a more general attention deficit seems to contribute to the more pronounced performance deficit pattern in ADHD.

Differential oscillatory electroencephalogram between attention-deficit/hyperactivity disorder subtypes and typically developing adolescents

BACKGROUND

A neurobiological-based classification of attention-deficit/hyperactivity disorder (ADHD) subtypes has thus far remained elusive. The aim of this study was to use oscillatory changes in the electroencephalogram (EEG) related to informative cue processing, motor preparation, and top-down control to investigate neurophysiological differences between typically developing (TD) adolescents, and those diagnosed with predominantly inattentive (IA) or combined (CB) (associated with symptoms of inattention as well as impulsivity/hyperactivity) subtypes of ADHD.

METHODS

The EEG was recorded from 57 rigorously screened adolescents (12 to 17 years of age; 23 TD, 17 IA, and 17 CB), while they performed a cued flanker task. We examined the oscillatory changes in theta (3-5 Hz), alpha (8-12 Hz), and beta (22-25 Hz) EEG bands after cues that informed participants with which hand they would subsequently be required to respond.

RESULTS

Relative to TD adolescents, the IA group showed significantly less postcue alpha suppression, suggesting diminished processing of the cue in the visual cortex, whereas the CB group showed significantly less beta suppression at the electrode contralateral to the cued response hand, suggesting poor motor planning. Finally, both ADHD subtypes showed weak functional connectivity between frontal theta and posterior alpha, suggesting common top-down control impairment.

CONCLUSIONS

We found both distinct and common task-related neurophysiological impairments in ADHD subtypes. Our results suggest that task-induced changes in EEG oscillations provide an objective measure, which in conjunction with other sources of information might help distinguish between ADHD subtypes and therefore aid in diagnoses and evaluation of treatment.

Prepotent response inhibition and interference control in autism spectrum disorders: two meta-analyses

There is a substantial amount of data providing evidence for, but also against the hypothesis that individuals with autism spectrum disorders (ASD) encounter inhibitory control deficits. ASD is often associated with interference control deficits rather than prepotent response inhibition. Moreover, the developmental trajectory for these inhibitory control processes is hypothesized to differ in ASD as compared to typical development. In efforts to gain a more comprehensive perspective of inhibition in ASD, separate quantitative analysis for prepotent response inhibition studies and interference control studies were conducted. Together, these two meta-analyses included 41 studies with a combined sample size of 1,091 people with ASD (M age 14.8 years), and 1,306 typically developing (TD) controls (M age 13.8 years).The meta-analyses indicated that individuals with ASD show increased difficulties in prepotent response inhibition (effect size 0.55) and in interference control (effect size 0.31). In addition, age was a relevant moderator for prepotent response inhibition but not for interference control. Exploratory analyses revealed that when IQ was taken into account, heterogeneity considerably decreased among interference control studies but not among prepotent response inhibition. In contrast to the general belief, both prepotent response inhibition and interference control problems were observed in individuals with ASD. However, a large variation between studies was also found. Therefore, there remain factors beyond inhibition type, age, or IQ that significantly influence inhibitory control performance among individuals with ASD.

Contributions of COMT Val¹⁵⁸ Met to cognitive stability and flexibility in infancy

Adaptive behavior requires focusing on relevant tasks while remaining sensitive to novel information. In adult studies of cognitive control, cognitive stability involves maintaining robust cognitive representations while cognitive flexibility involves updating of representations in response to novel information. Previous adult research has shown that the Met allele of the COMT Val(158) Met gene is associated with enhanced cognitive stability whereas the Val allele is associated with enhanced cognitive flexibility. Here we propose that the stability/flexibility framework can also be applied to infant research, with stability mapping onto early indices of behavioral regulation and flexibility mapping onto indices of behavioral reactivity. From this perspective, the present study examined whether COMT genotype was related to 7-month-old infants' reactivity to novel stimuli and behavioral regulation. Cognitive stability and flexibility were assessed using (1) a motor approach task, (2) a habituation task, and (3) a parental-report measure of temperament. Val carriers were faster to reach for novel toys during the motor approach task and received higher scores on the temperament measure of approach to novelty. Met carriers showed enhanced dishabituation to the novel stimulus during the habituation task and received higher scores on the temperament measures of sustained attention and behavioral regulation. Overall, these results are consistent with adult research suggesting that the Met and Val alleles are associated with increased cognitive stability and flexibility, respectively, and thus suggest that COMT genotype may similarly affect cognitive function in infancy.

Development of temperamental effortful control mediates the relationship between maturation of the prefrontal cortex and psychopathology during adolescence: a 4-year longitudinal study

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Longitudinal study investigating the relationship between development of cortical thickness and effortful control during adolescence.

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Examined whether change in effortful control mediated the relationship between cortical development and change in socioemotional functioning, including psychopathology symptoms.

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Greater cortical thinning of the left ACC was associated with superior development of effortful control.

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Changes in effortful control mediated the relationship between greater thinning of the left ACC and improvements in socioemotional functioning.

This study investigated the relationship between the development of effortful control (EC), a temperamental measure of self-regulation, and concurrent development of three regions of the prefrontal cortex (anterior cingulate cortex, ACC; dorsolateral prefrontal cortex, dlPFC; ventrolateral prefrontal cortex, vlPFC) between early- and mid-adolescence. It also examined whether development of EC mediated the relationship between cortical maturation and emotional and behavioral symptoms. Ninety-two adolescents underwent baseline assessments when they were approximately 12 years old and follow-up assessments approximately 4 years later. At each assessment, participants had MRI scans and completed the Early Adolescent Temperament Questionnaire-Revised, as well as measures of depressive and anxious symptoms, and aggressive and risk taking behavior. Cortical thicknesses of the ACC, dlPFC and vlPFC, estimated using the FreeSurfer software, were found to decrease over time. EC also decreased over time in females. Greater thinning of the left ACC was associated with less reduction in EC. Furthermore, change in effortful control mediated the relationship between greater thinning of the left ACC and improvements in socioemotional functioning, including reductions in psychopathological symptoms. These findings highlight the dynamic association between EC and the maturation of the anterior cingulate cortex, and the importance of this relationship for socioemotional functioning during adolescence.

Attention deficit hyperactivity disorder symptoms in adults with autism spectrum disorders

Features of attention deficit hyperactivity disorder (ADHD) and impairments on neuropsychological, tests of attention have been documented in children with autism spectrum disorders (ASDs). To date, there has been a lack of research comparing attention in adults with ASD and adults with ADHD. In study 1, 31 adults with ASD and average intellectual function completed self-report measures of ADHD symptoms. These were compared with self-report measures of ADHD symptoms in 38 adults with ADHD and 29 general population controls. In study 2, 28 adults with a diagnosis of ASD were compared with an age- and intelligence quotient-matched sample of 28 adults with ADHD across a range of measures of attention. Study 1 showed that 36.7% of adults with ASD met Diagnostic and Statistical Manual-IV criteria for current ADHD "caseness" (Barkley Current self-report scores questionnaire). Those with a diagnosis of pervasive developmental disorder-not otherwise specified were most likely to describe ADHD symptoms. The ASD group differed significantly from both the ADHD and control groups on total and individual symptom self-report scores. On neuropsychological testing, adults with ASD and ADHD showed comparable performance on tests of selective attention. Significant group differences were seen on measures of attentional switching; adults with ADHD were significantly faster and more inaccurate, and individuals with Asperger's syndrome showed a significantly slower and more accurate response style. Self-reported rates of ADHD among adults with ASD are significantly higher than in the general adult population and may be underdiagnosed. Adults with ASD have attentional difficulties on some neuropsychological measures.

Adjusting behavior to changing environmental demands with development

Plasticity refers to changes in the brain that enable an organism to adapt its behavior in the face of changing environmental demands. The evolutionary role of plasticity is to provide the cognitive flexibility to learn from experiences, to monitor the world based on learned predictions, and adjust actions when these predictions are violated. Both progressive (myelination) and regressive (synaptic pruning) brain changes support this type of adaptation. Experience-driven changes in neural connections underlie the ability to learn and update thoughts and behaviors throughout life. Many cognitive and behavioral indices exhibit nonlinear life-span trajectories, suggesting the existence of specific sensitive developmental periods of heightened plasticity. We propose that age-related differences in learning capabilities and behavioral performance reflect the distinct maturational timetable of subcortical learning systems and modulatory prefrontal regions. We focus specifically on the developmental transition of adolescence, during which individuals experience difficulty flexibly adjusting their behavior when confronted with unexpected and emotionally salient events. In this article, we review the findings illustrating this phenomenon and how they vary by individual.

Attention, task difficulty, and ADHD

Comments on analysis of attention tasks in Attention Deficit Hyperactivity Disorder (ADHD) provided by Wilding (2005) points out that whereas many regulatory functions, including alertness or arousal, appear to be impaired in ADHD, demonstrating basic attention deficits in selection or orienting functions in the disorder has proven difficult. Yet several issues remain to be addressed in the field with regard to attentional function in ADHD. These include the need for further scrutiny of effects of perceptual load, the psychometric problem of differential task difficulty and differential deficit, relative value of complex versus simple tasks, and consideration of heterogeneity in ADHD. Heterogeneity pertains both to additional analysis of ADHD subtypes, in light of speculation that the Inattentive type may be characterized by true attention problems, and to newer analyses of potential distinct etiological groups within subtype. New analyses of attentional operations have a role to play in these future directions.

Neuroimaging evidence for processes underlying repetition of ignored stimuli

Prolonged response times are observed with targets having been presented as distractors immediately before, called negative priming effect. Among others, inhibitory and retrieval processes have been suggested underlying this behavioral effect. As those processes would involve different neural activation patterns, a functional magnetic resonance imaging (fMRI) study including 28 subjects was conducted. Two tasks were used to investigate stimulus repetition effects. One task focused on target location, the other on target identity. Both tasks are known to elicit the expected response time effects. However, there is less agreement about the relationship of those tasks with the explanatory accounts under consideration. Based on within-subject comparisons we found clear differences between the experimental repetition conditions and the neutral control condition on neural level for both tasks. Hemodynamic fronto-striatal activation patterns occurred for the location-based task favoring the selective inhibition account. Hippocampal activation found for the identity-based task suggests an assignment to the retrieval account; however, this task lacked a behavioral effect.

Response inhibition in adults with autism spectrum disorder compared to attention deficit/hyperactivity disorder

Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) are hypothesised to involve core deficits in executive function. Previous studies have found evidence of a double dissociation between the disorders on specific executive functions (planning and response inhibition). To date most research has been conducted with children. No studies have directly compared the stable cognitive profile of adults. It was hypothesised that adults with ASD would show generally intact response inhibition whereas those with ADHD would show more global impairment. Participants were 24 adults aged 18-55 with high functioning ASD, 24 with ADHD, and 14 age and IQ matched controls. Participants completed three standardised measures of response inhibition. Participants with ASD had generally intact response inhibition but slow response latencies, possibly due to deficits in response initiation. Adults with ADHD did not show the more global impairments hypothesised. There were some significant differences between the clinical groups across measures of inhibition. In terms of performance style, adults with ASD were slow and accurate whilst those with ADHD showed an impulsive style.

Psychopathological aspects of dopaminergic gene polymorphisms in adolescence and young adulthood

Dopamine hypotheses of several psychiatric disorders are based upon the clinical benefits of drugs affecting dopamine transporter or receptors, and have prompted intensive candidate gene research within the dopaminergic system during the last two decades. The aim of this review is to survey the most important findings concerning dopaminergic gene polymorphisms in attention deficit hyperactivity disorder (ADHD), Tourette syndrome (TS), obsessive compulsive disorder, and substance abuse. Also, genetic findings of related phenotypes, such as inattention, impulsivity, aggressive behavior, and novelty seeking personality trait are presented, because recent studies have applied quantitative trait measures using questionnaires, symptom scales, or other objective endophenotypes. Unfortunately, genetic variants with minor effects are problematic to detect in these complex inheritance disorders, often leading to contradictory results. The most consistent association findings relate to ADHD and the dopamine transporter and the dopamine D4 receptor genes. Meta-analyses also support the association between substance abuse and the D2 receptor gene. The dopamine catabolizing enzyme genes, such as monoamine oxidase (MAO) A and catechol-O-methyltransferase (COMT) genes, have been linked to aggressive behaviors.

Planning: fixed-foreperiod event-related potentials during the Tower of London task

Slow wave ERPs were recorded from 28 young adults as they generated plans for various difficulty levels of a fixed-foreperiod version of the Tower of London task. The resulting waveform included three segments: (1) a left-lateralized negative early-interval wave, which was frontally maximal but not sensitive to difficulty, (2) a right-lateralized frontally maximal mid-interval wave, which was more positive for more difficult problems, and (3) a left lateralized centrally maximal negative-ramping contingent negative variation (CNV) late wave, which was more negative for more difficult problems. The current study adds to the current literature in that it finds that the frontal and central neural utilization with difficulty changes across plan generation. This suggests that plan generation should be considered in terms of when component processes of planning are differentially utilized as plan generation unfolds.

College Students With ADHD

Attention deficit hyperactivity disorder (ADHD) is the second most endorsed disability among college populations today, totaling approximately 11%. ADHD causes significant problems in education and social and occupational functioning of college students as well as in their postcollege work environment. Although the literature is replete with information guiding service providers working with students in other areas, very few studies exists to help career counselors who work with college students with ADHD. This article attempts to fill the gap by highlighting (a) college and postcollege work implications of ADHD characteristics and (b) effective interventions that counselors can implement to buttress the career planning process and postcollege occupational success for students with ADHD.