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Current evidence suggests that attention deficit hyperactivity disorder (ADHD) involves dysfunction in wide functional networks of brain areas associated with attention and cognition. This study examines the structural integrity of white-matter neural pathways, which underpin these functional networks, connecting fronto-striatal and fronto-parietal circuits, in children with ADHD. Fifteen right-handed 8 to 18-year-old males with ADHD-combined type and 15 right-handed, age, verbal, and performance IQ-matched, healthy males underwent diffusion tensor imaging. A recent method of tract-based spatial statistics was used to examine fractional anisotropy (FA) and mean diffusivity within major white-matter pathways throughout the whole-brain. White-matter abnormalities were found in several distinct clusters within left fronto-temporal regions and right parietal-occipital regions. Specifically, participants with ADHD showed greater FA in white-matter regions underlying inferior parietal, occipito-parietal, inferior frontal, and inferior temporal cortex. Secondly, eigenvalue analysis suggests that the difference in FA in ADHD may relate to a lesser degree of neural branching within key white-matter pathways. Tractography methods showed these regions to generally form part of white-matter pathways connecting prefrontal and parieto-occipital areas with the striatum and the cerebellum. Our findings demonstrate anomalous white-matter development in ADHD in distinct cortical regions that have previously been shown to be dysfunctional or hypoactive in fMRI studies of ADHD. These data add to an emerging picture of abnormal development within fronto-parietal cortical networks that may underpin the cognitive and attentional disturbances associated with ADHD.

This is the first evaluation of the efficacy for a course of oxytocin treatment for youth with ASD. Although results did not suggest clinical efficacy, further research is needed to explore alternative delivery methods, earlier age of intervention, and the influence of caregiver expectation on treatment response.

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This paper examines upper-body movement kinematics in individuals with high-functioning autism (HFA) and Asperger's disorder (AD). In general, the results indicate that HFA is more consistently associated with impaired motoric preparation/initiation than AD. The data further suggest that this quantitative difference in motor impairment is not necessarily underpinned by greater executive dysfunction vulnerability in autism relative to AD. Quantitative motoric dissociation between autism and AD may have down-stream effects on later stages of movement resulting in qualitative differences between these disorder groups, e.g. "motor clumsiness" in AD versus "abnormal posturing" in autism. It will be important for future research to map the developmental trajectory of motor abnormalities in these disorder groups. KeywordsHigh-functioning autism; Asperger's disorder; Movement kinematics; Motor preparation kinematics; Motor preparation Autism is a pervasive developmental condition defined by impairments in communication, social reciprocity, and repetitive-stereotyped behavioral patterns (American Psychiatric Association, 1994). Although motor functioning deficits are widely reported in the literature (Berkeley, Zittel, Pitney, & Nichols, 2001;Beversdorf et al., 2001;Brasic & Barnett, 1997;Ghaziuddin, Butler, Tsai, & Ghaziuddin, 1994;Manjiviona & Prior, 1995;Miyahara et al., 1997;Rinehart et al., 2001a), there is debate about how to describe and define motor abnormalities in this population (e.g. clumsy movement versus poorly coordinated movement versus poorly planned movement), and debate about whether the nature of motor

Autism Spectrum Disorder affects up to 2.5% of children and is associated with harmful health outcomes (e.g. obesity). Low levels of physical activity and high levels of sedentary behaviors may contribute to harmful health outcomes. To systematically review the prevalence and correlates of physical activity and sedentary behaviors in children with Autism Spectrum Disorder, electronic databases (PsycINFO, SPORTDiscus, EMBASE, Medline) were searched from inception to November 2015. The review was registered with PROSPERO (CRD42014013849). Peer-reviewed, English language studies were included. Two reviewers screened potentially relevant articles. Outcomes of interest were physical activity and sedentary behaviour levels and their potential correlates. Data were collected and analysed in 2015. Of 35 included studies, 15 reported physical activity prevalence, 10 reported physical activity correlates, 18 reported sedentary behavior prevalence, and 10 reported sedentary behavior correlates. Estimates of children’s physical activity (34–166 mins/day, average 86 mins/day) and sedentary behavior (126–558 mins/day in screen time, average 271 mins/day; 428–750 mins/day in total sedentary behavior, average 479 mins/day) varied across studies. Age was consistently inversely associated, and sex inconsistently associated with physical activity. Age and sex were inconsistently associated with sedentary behavior. Sample sizes were small. All but one of the studies were classified as having high risk of bias. Few correlates have been reported in sufficient studies to provide overall estimates of associations. Potential correlates in the physical environment remain largely unexamined. This review highlights varying levels of physical activity and sedentary behavior in children with Autism Spectrum Disorder. Research is needed to consistently identify the correlates of these behaviors. There is a critical need for interventions to support healthy levels of these behaviors.

Attention deficit hyperactivity disorder, combined type (ADHD-CT) is associated with spatial working memory deficits. These deficits are known to be subserved by dysfunction of neural circuits involving right prefrontal, striatal and parietal brain regions. This study determines whether decreased right prefrontal, striatal and parietal activation with a mental rotation task shown in adolescents with ADHD-CT is also evident in children with ADHD-CT. A crosssectional study of 12 pre-pubertal, right-handed, 8-12-year-old boys with ADHD-CT and 12 prepubertal, right-handed, performance IQ-matched, 8-12-year-old healthy boys, recruited from local primary schools, was completed. Participants underwent functional magnetic resonance imaging while performing a mental rotation task that requires spatial working memory. The two groups did not differ in their accuracy or response times for the mental rotation task. The ADHD-CT group showed significantly less activation in right parieto-occipital areas (cuneus and precuneus, BA 19), the right inferior parietal lobe (BA 40) and the right caudate nucleus. Our findings with a child cohort confirm previous reports of right striatal-parietal dysfunction in adolescents with ADHD-CT. This dysfunction suggests a widespread maturational deficit that may be developmental stage independent.