@article{oai:hama-med.repo.nii.ac.jp:00004052, author = {Murayama, Chihiro and Iwabuchi, Toshiki and Kato, Yasuhiko and Yokokura, Masamichi and Harada, Taeko and Goto, Takafumi and Tamayama, Taishi and Kameno, Yosuke and Wakuda, Tomoyasu and Kuwabara, Hitoshi and Senju, Atsushi and Nishizawa, Sadahiko and Ouchi, Yasuomi and Yamasue, Hidenori}, issue = {4}, journal = {Molecular Psychiatry}, month = {Apr}, note = {The social motivation hypothesis of autism proposes that social communication symptoms in autism spectrum disorder (ASD) stem from atypical social attention and reward networks, where dopamine acts as a crucial mediator. However, despite evidence indicating that individuals with ASD show atypical activation in extrastriatal regions while processing reward and social stimuli, no previous studies have measured extrastriatal dopamine D2/3 receptor (D2/3R) availability in ASD. Here, we investigated extrastriatal D2/3R availability in individuals with ASD and its association with ASD social communication symptoms using positron emission tomography (PET). Moreover, we employed a whole-brain multivariate pattern analysis of resting-state functional magnetic resonance imaging (fMRI) to identify regions where functional connectivity atypically correlates with D2/3R availability depending on ASD diagnosis. Twenty-two psychotropic-free males with ASD and 24 age- and intelligence quotient-matched typically developing males underwent [11C]FLB457 PET, fMRI, and clinical symptom assessment. Participants with ASD showed lower D2/3R availability throughout the D2/3R-rich extrastriatal regions of the dopaminergic pathways. Among these, the posterior region of the thalamus, which primarily comprises the pulvinar, displayed the largest effect size for the lower D2/3R availability, which correlated with a higher score on the Social Affect domain of the Autism Diagnostic Observation Schedule-2 in participants with ASD. Moreover, lower D2/3R availability was correlated with lower functional connectivity of the thalamus-superior temporal sulcus and cerebellum-medial occipital cortex, specifically in individuals with ASD. The current findings provide novel molecular evidence for the social motivation theory of autism and offer a novel therapeutic target.}, pages = {2106--2113}, title = {Extrastriatal dopamine D2/3 receptor binding, functional connectivity, and autism socio-communicational deficits: a PET and fMRI study}, volume = {27}, year = {2022} }