Feedforward and Feedback Motor Control Abnormalities Implicate Cerebellar Dysfunctions in Autism Spectrum Disorder
Feedforward and Feedback Motor Control Abnormalities Implicate Cerebellar Dysfunctions in Autism Spectrum Disorder
复制标题
DOI：
10.1523/jneurosci.2731-14.2015
复制
发表时间：
2015-02-04
影响因子：
5.3
通讯作者：
Sweeney, John A.
中科院分区：
文献类型：
--
作者：
Mosconi, Matthew W.;Mohanty, Suman;Sweeney, John A.
感觉运动异常在自闭症谱系障碍（ASD）中很常见，并且是该障碍的最早表现之一。它们的研究远远少于定义ASD的社交和认知缺陷，但对ASD中感觉运动异常的机械理解可能会为该疾病的神经基础提供关键见解。在这项人体研究中，我们检查了快速，精确的握力收缩，以确定是否前馈机制支持初始运动输出之前，感觉反馈可以处理被破坏的ASD。持续的力量收缩也进行了检查，以确定是否反应性调整正在进行的运动行为的基础上视觉反馈的改变。持续的力量进行了研究，在多个力水平和视觉增益，以评估运动和视觉机制，分别。ASD患者的主力收缩表现出更大的峰值力增加率和大的瞬时过冲。患有ASD的个体也表现出持续的力变异性增加，其随力水平而增加，并且当视觉增益高度放大或高度退化时更为严重。当维持恒定的力水平时，他们的反应性调整比对照组更周期性，并且他们表现出对较慢反馈机制的依赖性增加。前馈和反馈机制的改变都与ASD中更严重的社交障碍相关。这些研究结果涉及前小脑电路参与前馈运动控制和后小脑电路参与将视觉反馈转化为精确的运动调整在ASD。
Sensorimotor abnormalities are common in autism spectrum disorder (ASD) and among the earliest manifestations of the disorder. They have been studied far less than the social-communication and cognitive deficits that define ASD, but a mechanistic understanding of sensorimotor abnormalities in ASD may provide key insights into the neural underpinnings of the disorder. In this human study, we examined rapid, precision grip force contractions to determine whether feedforward mechanisms supporting initial motor output before sensory feedback can be processed are disrupted in ASD. Sustained force contractions also were examined to determine whether reactive adjustments to ongoing motor behavior based on visual feedback are altered. Sustained force was studied across multiple force levels and visual gains to assess motor and visuomotor mechanisms, respectively. Primary force contractions of individuals with ASD showed greater peak rate of force increases and large transient overshoots. Individuals with ASD also showed increased sustained force variability that scaled with force level and was more severe when visual gain was highly amplified or highly degraded. When sustaining a constant force level, their reactive adjustments were more periodic than controls, and they showed increased reliance on slower feedback mechanisms. Feedforward and feedback mechanism alterations each were associated with more severe social-communication impairments in ASD. These findings implicate anterior cerebellar circuits involved in feedforward motor control and posterior cerebellar circuits involved in transforming visual feedback into precise motor adjustments in ASD.