UCLA

The cerebellum plays a key role in sensorimotor coordination and has been repeatedly reported to be structurally and functionally altered in individuals with autism spectrum disorder (ASD). Atypicalities in the ASD cerebellum have also been linked to multiple ASD symptoms, including general sensory processing atypicalities. The vast majority of autistic youth have sensory processing atypicalities, with sensory over-responsivity (SOR) in particular being a common challenge to their quality of life. SOR has been associated with poor social adaptive, emotional and daily-life skills. Despite its impairing effect on the daily functioning of children with ASD, there are currently few evidence-based treatments for SOR. While cerebellar atypicalities may have direct links with SOR symptoms, to our knowledge, no studies previously investigated the link between cerebellar function and SOR in ASD. In the current dissertation study, I examined the role of cerebellar function in autistic youth with varying degrees of SOR. In three studies, I characterized functional alterations in the ASD cerebellum at rest (Study 1) and during sensory exposure (Studies 2 and 3), and investigated how these atypicalities relate to SOR. Moreover, I interrogated associations between cerebellar function during sensory stimulation and previously identified neural markers of SOR, sensory-limbic habituation (Study 2) and thalamic inhibition (Study 3). My findings implicate cerebellar atypicalities in the neural basis of SOR symptoms in ASD youth. Characterizing the neural basis of SOR is an important step towards formulating effective interventions to improve the everyday lives of children with ASD who experience SOR and ensuring that treatment is personalized based on individual differences in ASD-related symptomatology.