Executive Function Brain Network Activation Predicts Driving Hazard Detection in ADHD.

Drivers with neurodevelopmental disorders (NDDs), such as autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are at increased risk of experiencing driving difficulties. An important aspect of driving safety and skill involves hazard detection. This functional magnetic resonance imaging study examined the neural responses associated with driving hazard detection in drivers with ASD, ADHD, and typically developing (TD) drivers. Forty participants (12 ASD, 15 ADHD, 13 TD) ages 16-30 years completed a driving simulator task in which they encountered social and nonsocial hazards; reaction time (RT) for responding to hazards was measured. Participants then completed a similar hazard detection task in the MRI scanner so that neural response to hazards could be measured. Activation of regions of interest considered part of the executive function (EF) and theory of mind (ToM) networks were examined and related to driving simulator behavior. Results showed that stronger activation of the EF network during social hazard processing, including the bilateral dorsolateral prefrontal cortex and posterior parietal cortex, was associated with faster RT to social hazards among drivers with ADHD, but not among drivers with ASD. This provides the first evidence of a relationship between EF network brain activation and driving skills in ADHD and suggests that alterations in this network may underlie driving behavior. In comparison, the current study did not observe a relationship between ToM network activation and RT to social hazards in any group. This study lays the groundwork for relating neural activation to driving behavior among individuals with NDDs.

Neuropsychological predictors of driving hazard detection in autism spectrum disorder and ADHD.

Driving is a neuropsychologically complex task; this can present challenges for individuals with neurodevelopmental disorders (NDDs) such asautism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). Deficits in theory of mind (ToM) and executive function (EF) are common features of ASD and ADHD, respectively, and may influence driving processes such as hazard perception. No studies have directly examined the neuropsychological contributions to hazard detection among drivers with ASD compared to ADHD.In the current study, 48 participants ages 16-30 years (13 ASD, 17 ADHD, 18 typically developing (TD)) completed a driving simulator task in which they encountered hazards in the driving environment. Hazards varied in whether they were social (contained a human component) or nonsocial (were physical objects) to examine the contribution of ToM and social processing to hazard response. Additionally, participants completed a neuropsychological battery targeting ToM and EF/attention skills (cognitive tasks and self-report measures).Within the ASD group, participants responded relatively slower to social compared to nonsocial hazards; no effect of hazard type was observed in the ADHD or TD groups. Additionally, measures of ToM and EF were correlated with driving performanceamong ASD participants; within the ADHD group, only self-reported behavior regulation was associated with driving performance. Broadly, this suggests that cognitive factors such as ToM and EF impact driving hazard performance in ASD and ADHD. The results of the study have implications for developing driving intervention programs for individuals with NDDs.

Metacognition and behavioral regulation predict distinct aspects of social functioning in autism spectrum disorder.

Executive function (EF) deficits are common in autism spectrum disorder (ASD), and previous studies suggest that EF may influence or predict social functioning. Thus, EF is a potential treatment target in this population. However, the nature of how specific metacognition and behavioral regulation components of EF may differentially impact social function remains unclear. The goal of the current study was to examine the relationships between sub-components of EF (e.g., working memory, shifting, inhibition, etc.) and social functioning as measured by parent ratings on the Behavior Rating Inventory of Executive Functioning (BRIEF) and the Social Responsiveness Scale (SRS), while controlling for the influence of age, sex, and IQ. A second goal was to examine whether BRIEF scores were predictive of clinician-rated measures of ASD symptoms. Behavioral data were acquired from the Autism Brain Imaging Data Exchange-II database and included 106 children with ASD (ages 5-13). Based on analysis of parent ratings, self-monitoring skills predicted social awareness; shifting ability predicted social cognition; working memory and monitoring skills predicted social communication; initiation predicted social motivation; and shifting ability predicted restrictive and repetitive behaviors among children with ASD. Parent ratings on the BRIEF did not predict clinician-rated measures of ASD symptoms; this requires further study. Overall, the current findings indicate that metacognition and behavioral regulation both contribute to social functioning in ASD, although they each have distinct patterns of influence on different aspects of social functioning. These findings have promising implications for tailoring social interventions for ASD that target specific EF skills.

Patterns of Cerebellar Connectivity with Intrinsic Connectivity Networks in Autism Spectrum Disorders.

There is growing evidence of altered connectivity in autism spectrum disorders (ASD) between the cerebellum and cortex. Three intrinsic connectivity networks (ICNs) are especially important to cognitive processing in ASD: the default mode network (DMN), executive control network (ECN), and salience networks (SNs). The goal of this study was to compare resting-state functional connectivity between the cerebellum and the DMN, ECN, and SN in ASD and typically developing children (n = 74, ages 7-12 years). Children with ASD showed stronger connectivity between the ventral DMN and left cerebellar lobules I-IV. No meaningful relationships were observed between ICN-cerebellar functional connectivity and ASD symptoms. These results suggest that the cerebellum contributes to altered network connectivity in ASD.

Advances, challenges, and promises in pediatric neuroimaging of neurodevelopmental disorders.

Recent years have witnessed the proliferation of neuroimaging studies of neurodevelopmental disorders (NDDs), particularly of children with autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and Tourette's syndrome (TS). Neuroimaging offers immense potential in understanding the biology of these disorders, and how it relates to clinical symptoms. Neuroimaging techniques, in the long run, may help identify neurobiological markers to assist clinical diagnosis and treatment. However, methodological challenges have affected the progress of clinical neuroimaging. This paper reviews the methodological challenges involved in imaging children with NDDs. Specific topics include correcting for head motion, normalization using pediatric brain templates, accounting for psychotropic medication use, delineating complex developmental trajectories, and overcoming smaller sample sizes. The potential of neuroimaging-based biomarkers and the utility of implementing neuroimaging in a clinical setting are also discussed. Data-sharing approaches, technological advances, and an increase in the number of longitudinal, prospective studies are recommended as future directions. Significant advances have been made already, and future decades will continue to see innovative progress in neuroimaging research endeavors of NDDs.

The impact of atypical sensory processing on social impairments in autism spectrum disorder.

Altered sensory processing has been an important feature of the clinical descriptions of autism spectrum disorder (ASD). There is evidence that sensory dysregulation arises early in the progression of ASD and impacts social functioning. This paper reviews behavioral and neurobiological evidence that describes how sensory deficits across multiple modalities (vision, hearing, touch, olfaction, gustation, and multisensory integration) could impact social functions in ASD. Theoretical models of ASD and their implications for the relationship between sensory and social functioning are discussed. Furthermore, neural differences in anatomy, function, and connectivity of different regions underlying sensory and social processing are also discussed. We conclude that there are multiple mechanisms through which early sensory dysregulation in ASD could cascade into social deficits across development. Future research is needed to clarify these mechanisms, and specific focus should be given to distinguish between deficits in primary sensory processing and altered top-down attentional and cognitive processes.

"Decoding versus comprehension": Brain responses underlying reading comprehension in children with autism.

Despite intact decoding ability, deficits in reading comprehension are relatively common in children with autism spectrum disorders (ASD). However, few neuroimaging studies have tested the neural bases of this specific profile of reading deficit in ASD. This fMRI study examined activation and synchronization of the brain's reading network in children with ASD with specific reading comprehension deficits during a word similarities task. Thirteen typically developing children and 18 children with ASD performed the task in the MRI scanner. No statistically significant group differences in functional activation were observed; however, children with ASD showed decreased functional connectivity between the left inferior frontal gyrus (LIFG) and the left inferior occipital gyrus (LIOG). In addition, reading comprehension ability significantly positively predicted functional connectivity between the LIFG and left thalamus (LTHAL) among all subjects. The results of this study provide evidence for altered recruitment of reading-related neural resources in ASD children and suggest specific weaknesses in top-down modulation of semantic processing.