Abnormal Cortico-Cerebellar Functional Connectivity in Autism Spectrum Disorder.

Taiane Coelho Ramos,André Fujita,Joana Bisol Balardin,João Ricardo Sato

doi:10.3389/fnsys.2018.00074

Abstract

The cerebral cortex and the cerebellum are spatially remote areas that are connected by complex circuits that link both primary and associative areas. Previous studies have revealed abnormalities in autism spectrum disorder (ASD); however, it is not clear whether cortico-cerebellar connectivity is differentially manifested in the disorder. To explore this issue, we investigated differences in intrinsic cortico-cerebellar functional connectivity between individuals with typical development (TD) and those with ASD. To this end, we used functional magnetic resonance imaging (fMRI) of 708 subjects under a resting state protocol provided by the ABIDE I Consortium. We found that people with ASD had diminished functional connectivity between the cerebellum and the following cortical regions: (i) right fusiform gyrus, (ii) right postcentral gyrus, (iii) right superior temporal gyrus, (iv) right middle temporal gyrus, and (v) left middle temporal gyrus. All of these regions are involved in many cognitive systems that contribute to commonly affected functions in ASD. For right fusiform gyrus, right superior temporal gyrus, and left middle temporal gyrus, we reproduced the results in an independent cohort composed of 585 subjects of the ABIDE II Consortium. Our results points toward a consistent atypical cortico-cerebellar connectivity in ASD.

Highlights

Autism spectrum disorders (ASD) are mainly characterized by repetitive behavior and social impairment, including differentiated sensitivity to sound and touch and difficulty in recognizing non-verbal language and facial expressions (American Psychiatric Association, 2013)
We identified five cortical ROIs (Figure 1) that are differentially associated with the cerebellum between the typical development (TD) and autism spectrum disorder (ASD) groups, namely, the right fusiform gyrus [β = −0.042, t-value = −3.689, p = 0.005 —t-test (GLM)], the right postcentral gyrus [β = −0.038, t-value = −3.131, p = 0.027 — t-test (GLM)], the right superior temporal gyrus [β = −0.034, t-value = −3.082, p = 0.027 –t-test (GLM)], the right middle temporal gyrus [β = −0.039, t-value = −3.783, p < 0.001 —t-test (GLM)], and the left middle temporal gyrus [β = −0.056, t-value = −5.481, p = 0.005 —t-test (GLM)]
We investigated the differences in the intrinsic cortico-cerebellar functional connectivity between individuals with TD and those with ASD

Summary

Introduction

Autism spectrum disorders (ASD) are mainly characterized by repetitive behavior and social impairment, including differentiated sensitivity to sound and touch and difficulty in recognizing non-verbal language and facial expressions (American Psychiatric Association, 2013). These symptoms may affect a child’s cognitive development, which may prevent self-sufficiency in adulthood. One out of 68 children in the U.S (Christensen, 2016) and 1% of the population worldwide (Elsabbagh et al, 2012) are estimated to have ASD. Cerebellar lesions in premature children may result in symptoms similar to ASD (Limperopoulos et al, 2014)

Methods

Results

Conclusion