Early Sleep and Sensory Over-Responsivity Relate to Insular Functional Connectivity with Sensorimotor Cortices and Cerebellum in Infants at Varying Likelihood for Autism

Sleep problems and sensory over-responsivity (SOR) are common, co-occurring, and early emerging features of Autism Spectrum Disorder (ASD). Yet, the early neural mechanisms underlying these symptoms remain unclear. Here, we used resting-state fMRI data from the Infant Brain Imaging Study (IBIS) to examine how functional brain connectivity at 6 months may relate to parent-reported measures of sleep-onset problems and SOR in infants at varying familial likelihood for ASD. The right anterior insula (rAI) – a key hub of the salience network – was used in ROI-ROI analyses to investigate functional connectivity to cortical and cerebellar regions previously implicated in sleep disruption, sensory processing challenges, and ASD. Infants at high (HL) and low (LL) likelihood for ASD displayed divergent patterns of rAI connectivity with sensorimotor cortex, as well as cerebellar regions involved in sensorimotor processing and higher-order functions. Furthermore, stronger rAI connectivity with sensorimotor cortices and cerebellar regions was associated with worse sleep-onset problems and SOR in HL infants. In contrast, stronger rAI-cerebellar connectivity was related to fewer sleep-onset problems and SOR in LL infants. Our findings indicate that altered rAI connectivity may result in over-attribution of attention to sensory stimuli and highlight aberrant sensory prediction learning, which may underlie worse sleep problems and higher SOR in HL infants.