31895
Cortical Folding Differences in Autism Spectrum Disorder (ASD) and Attention-Deficit/ Hyperactivity Disorder (ADHD) Relative to Typically Developing Peers (TD): Data from the Pond Network

Poster Presentation
Thursday, May 2, 2019: 5:30 PM-7:00 PM
Room: 710 (Palais des congres de Montreal)
A. Gharehgazlou1,2, S. Ameis3,4,5, M. J. Taylor1,6,7,8,9, J. P. Lerch1,8,9,10, M. M. Vandewouw8,11, J. A. Brian12, J. Crosbie13, R. Schachar14 and E. Anagnostou1,8,12,15, (1)Institute of Medical Science, University of Toronto, Toronto, ON, Canada, (2)Autism Research Centre, Holland Bloorview Kids Rehabilitation Hospital, Toronto, ON, Canada, (3)Department of Psychiatry, University of Toronto, Toronto, ON, Canada, (4)Program in Brain and Mental Health, The Hospital for Sick Children, Toronto, ON, Canada, (5)The Margaret and Wallace McCain Centre for Child, Youth, & Family Mental Health, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada, (6)The Hospital for Sick Children, Toronto, ON, Canada, (7)Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada, (8)Neuroscience & Mental Health Program, The Hospital for Sick Children Research Institute, Toronto, ON, Canada, (9)Department of Medical Imaging, University of Toronto, Toronto, ON, Canada, (10)Mouse Imaging Centre, Hospital for Sick Children, Toronto, ON, Canada, (11)Diagnostic Imaging, Hospital for Sick Children, Toronto, ON, Canada, (12)Holland Bloorview Kids Rehabilitation Hospital, Toronto, ON, Canada, (13)Psychology, The Hospital for Sick Children, Toronto, ON, Canada, (14)Psychiatry, The Hospital for Sick Children, Toronto, ON, Canada, (15)Department of Pediatrics, University of Toronto, Toronto, ON, Canada
Background: ASD and ADHD are relatively common neurodevelopmental disorders (NDDs), with onset in early childhood. Due to their high comorbidity and rate of co-occurring symptoms, investigation of both NDDs in a single cohort will add clarity to our understanding of the shared and disorder-specific underlying neurobiological mechanisms that may drive these conditions. Magnetic resonance imaging (MRI) has been used extensively to study atypical brain development in both NDDs, however, cortical folding as a specific measure derived from MRI has received less attention.

The limited number of studies that have investigated cortical folding in ASD and ADHD present contradictory results. To the best of our knowledge, no study has investigated cortical folding across individuals with ASD and ADHD and typically developing controls (TD), and little is known about the relation of this measure to clinical symptoms.

Objectives: We examined cortical folding in children and adolescents with ASD and ADHD relative to TD, and the relation between cortical folding and social, attention, behavioural and adaptive functioning difficulties across disorders.

Methods: T1-weighted MRI, cognitive and behavioural data of children and adolescents with ASD, ADHD and TD, between 6.1-15.9 years of age, were obtained from the Province of Ontario Neurodevelopmental Disorders (POND) Network dataset, an Ontario Brain Institute-funded multi-site study. FreeSurfer software was used to obtain whole-brain 3-D measures of cortical folding using local Gyrification Index (lGI), a surface-based measure providing vertex-wise quantification of cortical folding. General linear model (GLM) analyses was conducted, on the module QDEC (Query, Design, Estimate, Contrast) on FreeSurfer to examine lGI differences between groups.

Results: 42 ASD (mean age: 12.11, SD: 2.76), 17 ADHD (mean age: 11.97, SD: 2.43) and 76 TD (mean age: 12.79, SD: 3.11) participants with IQ>70 were included in this preliminary study, which revealed significantly reduced cortical folding in individuals with NDDs relative to controls in a left hemisphere cluster located in the superior parietal lobe (p<0.0001). No significant difference in cortical folding was found on comparison of ASD versus ADHD groups. Decrease in cortical folding was associated with better adaptive functioning, less hyperactive/impulsive & inattention impairments, but more repetitive behaviours across all children with NDDs. No significant relation was found between cortical folding and social communication deficits. All results were corrected for multiple comparisons using Monte-Carlo simulations.

Conclusions: Findings of cortical folding differences in individuals with ASD and ADHD relative to TD point to an early marker of altered development in these conditions that predates clinical onset and may drive other brain alternations. Findings of no significant differences between ASD and ADHD suggests further similarities between these two NDDs.

See more of: Neuroimaging
See more of: Neuroimaging