Translational Magnetic Resonance Imaging in Autism Spectrum Disorder From the Mouse Model to Human

Abstract

Autism spectrum disorder (ASD) is a heterogeneous syndrome characterized by behavioral features such as impaired social communication, repetitive behavior patterns, and a lack of interest in novel objects. A multimodal neuroimaging using magnetic resonance imaging (MRI) in patients with ASD shows highly heterogeneous abnormalities in function and structure in the brain associated with specific behavioral features. To elucidate the mechanism of ASD, several ASD mouse models have been generated, by focusing on some of the ASD risk genes. A specific behavioral feature of an ASD mouse model is caused by an altered gene expression or a modification of a gene product. Using these mouse models, a high field preclinical MRI enables us to non-invasively investigate the neuronal mechanism of the altered brain function associated with the behavior and ASD risk genes. Thus, MRI is a promising translational approach to bridge the gap between mice and humans. This review presents the evidence for multimodal MRI, including functional MRI (fMRI), diffusion tensor imaging (DTI), and volumetric analysis, in ASD mouse models and in patients with ASD and discusses the future directions for the translational study of ASD.

Keywords: DTI; MRI; autism; functional connectivity; mouse; translational study.

FIGURE 1

Schematic figures of magnetic resonance imaging (MRI) analysis. (A) Functional MRI relies on the neuron-glia vascular interaction. (B) Fractional anisotropy (FA) is calculated in each voxel, and fiber tracking is calculated from diffusion tensor imaging (DTI). (C) For voxel-based morphometry (VBM), gray matter segmentation in each subject was performed, and the statistical difference in gray matter concentration between groups in each voxel was analyzed.