Mapping neural correlates of biological motion perception in autistic children using high-density diffuse optical tomography

Abstract

Autism spectrum disorder (ASD), a neurodevelopmental disorder defined by social communication deficits plus repetitive behaviors and restricted interests, currently affects 1/36 children in the general population. Recent advances in functional brain imaging show promise to provide useful biomarkers of ASD diagnostic likelihood, behavioral trait severity, and even response to therapeutic intervention. However, current gold-standard neuroimaging methods (e.g., functional magnetic resonance imaging) are limited in naturalistic studies of brain function underlying ASD-associated behaviors due to the constrained imaging environment. To overcome these limitations, we aimed to establish high-density diffuse optical tomography (HD-DOT), a non-invasive and minimally constraining optical neuroimaging modality, to evaluate brain function in autistic and non-autistic school-age children as they performed a biological motion perception task previously shown to yield results related to both ASD diagnosis and behavioral traits. Herein, we used HD-DOT to image brain function in 46 ASD school-age participants, 49 non-autistic controls (NAC), and 17 pro-band siblings as they viewed dynamic point-light displays of coherent biological and scrambled motion. We assessed group-level cortical brain function with statistical parametric mapping. Additionally, we tested for brain-behavior associations with dimensional metrics of autism traits, as measured with the Social Responsiveness Scale-2, with hierarchical regression models. We found that NAC participants presented stronger brain activity contrast (coherent > scrambled) than ASD children in cortical regions related to visual, motor, and social processing. Additionally, regression models revealed multiple cortical regions in autistic participants where brain function is significantly associated with dimensional measures of autism traits. This study demonstrates that HD-DOT is sensitive to brain function that both differentiates between NAC and ASD groups and correlates with dimensional measures of ASD traits. These findings establish HD-DOT as an effective tool for investigating brain function in autistic and non-autistic children and opens the door to future studies on brain function underlying natural behaviors. *Dr. Dalin Yang and Miss Alexandra Svoboda are designated as the co-first leading authors in the manuscript.