Baribeau D.A.,University of Toronto |
Anagnostou E.,Bloorview Research Institute
Frontiers in Psychiatry | Year: 2013
Background: Autism spectrum disorder (ASD) and childhood onset schizophrenia (COS) are pediatric neurodevelopmental disorders associated with significant morbidity. Both conditions are thought to share an underlying genetic architecture. A comparison of neuroimaging findings across ASD and COS with a focus on altered neurodevelopmental trajectories can shed light on potential clinical biomarkers and may highlight an underlying etiopathogenesis. Methods: A comprehensive review of the medical literature was conducted to summarize neuroimaging data with respect to both conditions in terms of structural imaging (including volumetric analysis, cortical thickness and morphology, and region of interest studies), white matter analysis (include volumetric analysis and diffusion tensor imaging) and functional connectivity. Results: In ASD, a pattern of early brain overgrowth in the first few years of life is followed by dysmaturation in adolescence. Functional analyses have suggested impaired long-range connectivity as well as increased local and/or subcortical connectivity in this condition. In COS, deficits in cerebral volume, cortical thickness, and white matter maturation seem most pronounced in childhood and adolescence, and may level off in adulthood. Deficits in local connectivity, with increased long-range connectivity have been proposed, in keeping with exaggerated cortical thinning. Conclusion: The neuroimaging literature supports a neurodevelopmental origin of both ASD and COS and provides evidence for dynamic changes in both conditions that vary across space and time in the developing brain. Looking forward, imaging studies which capture the early post natal period, which are longitudinal and prospective, and which maximize the signal to noise ratio across heterogeneous conditions will be required to translate research findings into a clinical environment. © 2013 Baribeau and Anagnostou.
Anagnostou E.,Bloorview Research Institute |
Taylor M.J.,University of Toronto
Molecular Autism | Year: 2011
Autism spectrum disorder (ASD) refers to a syndrome of social communication deficits and repetitive behaviors or restrictive interests. It remains a behaviorally defined syndrome with no reliable biological markers. The goal of this review is to summarize the available neuroimaging data and examine their implication for our understanding of the neurobiology of ASD. Although there is variability in the literature on structural magnetic resonance literature (MRI), there is evidence of volume abnormalities in both grey and white matter, with a suggestion of some region-specific differences. Early brain overgrowth is probably the most replicated finding in a subgroup of people with ASD, and new techniques, such as cortical-thickness measurements and surface morphometry have begun to elucidate in more detail the patterns of abnormalities as they evolve with age, and are implicating specific neuroanatomical or neurodevelopmental processes. Functional MRI and diffusion tensor imaging techniques suggest that such volume abnormalities are associated with atypical functional and structural connectivity in the brain, and researchers have begun to use magnetic resonance spectroscopy (MRS) techniques to explore the neurochemical substrate of such abnormalities. The data from multiple imaging methods suggests that ASD is associated with an atypically connected brain. We now need to further clarify such atypicalities, and start interpreting them in the context of what we already know about typical neurodevelopmental processes including migration and organization of the cortex. Such an approach will allow us to relate imaging findings not only to behavior, but also to genes and their expression, which may be related to such processes, and to further our understanding of the nature of neurobiologic abnormalities in ASD. © 2011 Anagnostou and Taylor; licensee BioMed Central Ltd.
Narayanan U.G.,University of Toronto |
Narayanan U.G.,Bloorview Research Institute
Journal of Pediatric Orthopaedics | Year: 2012
This article reviews the current best evidence for musculoskeletal interventions in children with ambulatory cerebral palsy (CP). The effectiveness of interventions in CP must first consider what CP and its associated pathophysiology are and take into account the heterogeneity and natural history of CP to put definitions of "effectiveness" into perspective. This article reviews the current standards of the definition and classification of CP, discusses the natural history and specific goals for the management of ambulatory CP, as well as the outcome measures available to measure these goals. The current best evidence of effectiveness is reviewed for specific interventions in children with ambulatory CP including spasticity management with botulinum toxin A injections and selective dorsal rhizotomy; multilevel orthopaedic surgery to address contractures and bony deformity; and the role of gait analysis for surgical decision-making before orthopaedic surgery. Copyright © 2012 by Lippincott Williams & Wilkins.
Biddiss E.,Bloorview Research Institute |
Irwin J.,University of Toronto
Archives of Pediatrics and Adolescent Medicine | Year: 2010
Objectives: To systematically review levels of metabolic expenditure and changes in activity patterns associated with active video game (AVG) play in children and to provide directions for future research efforts. Data Sources: A review of the English-language literature (January 1, 1998, to January 1, 2010) via ISI Web of Knowledge, PubMed, and Scholars Portal using the following keywords: video game, exergame, physical activity, fitness, exercise, energy metabolism, energy expenditure, heart rate, disability, injury, musculoskeletal, enjoyment, adherence, and motivation. Study Selection: Only studies involving youth (≤21years) and reporting measures of energy expenditure, activity patterns, physiological risks and benefits, and enjoyment and motivation associated with mainstream AVGs were included. Eighteen studies met the inclusion criteria. Articles were reviewed and data were extracted and synthesized by 2 independent reviewers. Main Outcome Exposures: Energy expenditure during AVG play compared with rest (12 studies) and activity associated with AVG exposure (6 studies). Main Outcome Measures: Percentage increase in energy expenditure and heart rate (from rest). Results: Activity levels duringAVGplay were highly variable, with mean (SD) percentage increases of 222% (100%) in energy expenditure and 64% (20%) in heart rate. Energy expenditure was significantly lower for games played primarily through upper body movements compared with those that engaged the lower body (difference, -148%; 95% confidence interval, -231% to -66%; P=.001). Conclusions: The AVGs enable light to moderate physical activity. Limited evidence is available to draw conclusions on the long-term efficacy of AVGs for physical activity promotion. ©2010 American Medical Association. All rights reserved.
Lindsay S.,Bloorview Research Institute |
Edwards A.,University of Toronto
Disability and Rehabilitation | Year: 2013
Purpose: Children's lack of knowledge about disability can adversely impact their attitudes toward people with disabilities. The purpose of this study is to review the common elements of effective disability awareness interventions. Methods: A systematic review of disability awareness interventions for children and youth was conducted to assess the effective components of these interventions. Electronic searches were conducted using OVID, CENTRAL, PsychInfo, ERIC, Social Science Citation Index, GreyNET Scopus and Google Scholar. The inclusion criteria included (i) an intervention raising awareness about disability, (ii) school-age children with the average age between 5-19 years old, (iii) at least one measurable outcome focusing on knowledge about disability or attitudes towards and/or acceptance of people with a disability and (iv) published article or grey literature. Results: Of the 1031 articles that were identified in the search, 42 met the criteria to be included in the review. We classified the disability awareness interventions into 5 broad types including (i) social contact, (ii) simulation, (iii) curriculum, (iv) multi-media curriculum and (v) multiple components. Thirty-four studies showed an improvement in attitudes towards and/or acceptance of peers with disabilities. Eight of these studies also demonstrated an improvement in knowledge of people with disabilities. Five of the interventions found no support for improving knowledge about, or acceptance of people with disabilities. Conclusion: Disability awareness interventions can successfully improve children's knowledge about and attitudes towards peers with a disability; they should include several different components over multiple sessions. Relevance: These findings are being used to further develop disability awareness interventions to help improve the social inclusion and participation of children with disabilities within mainstream classrooms. Implications for Rehabilitation Well-designed disability awareness interventions for children and youth can help improve knowledge about disability, attitudes towards people with a disability and acceptance of peers with a disability. Rehabilitation health care providers and educators should be trained to recognize when children with disabilities are being socially excluded and be prepared to provide or recommend appropriate resources and interventions on how to address this issue. Clinicians, educators and children with disabilities should all be involved in the development of disability awareness programs. Educators should carefully choose an appropriate intervention to meet the needs of the children in their class while considering age appropriateness and diversity of the students. It is also important for educators to be cognizant of the broader societal influences that impact attitudes towards disability. © 2013 Informa UK, Ltd.