PNAS：自闭症患儿无法体验语言的愉悦

日前，斯坦福大学医学院的科学家们发现，微弱的大脑连接可能妨碍患自闭症谱系障碍（ASD）的儿童感受到语言带来的愉悦。

自闭症谱系障碍（ASD）的一个特点就是对人类语音不敏感，而且一个著名的理论预测说，对大脑奖赏与情感系统的访问被削弱会阻止患自闭症谱系障碍（ASD）的个体积极地参与说话。

为了研究自闭症谱系障碍（ASD）的语音感受，研究人员比较了患自闭症谱系障碍（ASD）的儿童与典型发育的同年龄和同智商儿童的fMRI扫描。

研究人员把重点放在了称为后颞上沟（pSTS）的语音选择区域上，他们发现了自闭症谱系障碍（ASD）组的左半球后颞上沟（pSTS）与多巴胺能奖赏路径之间的连接相对较弱。

此外，研究人员在负责解释语调的右半球后颞上沟（pSTS）与情绪相关性学习所需的大脑中心之间观察到了与自闭症谱系障碍（ASD）有关的“连接不足”。

研究人员表示，进一步支持这些关系的是，连接不足的程度预测了自闭症谱系障碍（ASD）人群的交流缺陷的严重性。这些发现提示患自闭症谱系障碍（ASD）的儿童可能由于大脑的语言和奖赏中心之间的弱的连接而不能体验到人类语言带来的愉悦，而这种削弱反过来又会影响他们的社会交流技能。

Underconnectivity between voice-selective cortex and reward circuitry in children with autism
Abstract
Individuals with autism spectrum disorders (ASDs) often show insensitivity to the human voice, a deficit that is thought to play a key role in communication deficits in this population. The social motivation theory of ASD predicts that impaired function of reward and emotional systems impedes children with ASD from actively engaging with speech. Here we explore this theory by investigating distributed brain systems underlying human voice perception in children with ASD. Using resting-state functional MRI data acquired from 20 children with ASD and 19 age- and intelligence quotient-matched typically developing children, we examined intrinsic functional connectivity of voice-selective bilateral posterior superior temporal sulcus (pSTS). Children with ASD showed a striking pattern of underconnectivity between left-hemisphere pSTS and distributed nodes of the dopaminergic reward pathway, including bilateral ventral tegmental areas and nucleus accumbens, left-hemisphere insula, orbitofrontal cortex, and ventromedial prefrontal cortex. Children with ASD also showed underconnectivity between right-hemisphere pSTS, a region known for processing speech prosody, and the orbitofrontal cortex and amygdala, brain regions critical for emotion-related associative learning. The degree of underconnectivity between voice-selective cortex and reward pathways predicted symptom severity for communication deficits in children with ASD. Our results suggest that weak connectivity of voice-selective cortex and brain structures involved in reward and emotion may impair the ability of children with ASD to experience speech as a pleasurable stimulus, thereby impacting language and social skill development in this population. Our study provides support for the social motivation theory of ASD.