Replicability of reduced inter-subject functional connectivity in autism during movie-watching fMRI

Brisbane Convention & Exhibition Centre 

Autism is a neurodevelopmental condition characterized by impaired social communication and interaction, restricted interests, stereotyped behaviors, and altered sensory responses to external stimuli (American Psychiatric Association, 2013). Many autistic individuals without intellectual impairment perform well in controlled tasks, such as recognizing emotional facial expressions (Keating et al., 2023), but their performance often declines in naturalistic settings requiring implicit social processing (Van de Cruys et al., 2014). Functional magnetic resonance imaging (fMRI), during naturalistic stimuli, such as movies, has proven effective for examining social brain activity (Finn et al., 2020). Inter-subject functional connectivity (ISFC) measures the interregional connectivity across individuals, by separating the shared and stimulus-driven component of fMRI responses from intrinsic brain activity and noise (Simony et al., 2016). Previous findings suggest idiosyncratic inter-subject functional connectivity patterns in autistic individuals (Bolton et al., 2018), but the precise regional differences remain unclear and may vary across movie segments. Addressing the reproducibility crisis in neuroimaging (Kelly & Hoptman, 2022), cross-center experiment design can validate the generalizability of findings. This study aimed to investigate the difference of inter-subject functional connectivity between autistic individuals and neurotypical controls and to evaluate replication across datasets.