Motor stereotypies are rhythmic, repetitive, prolonged, predictable, and purposeless movements that stop with distraction. Although once believed to occur only in children with neurodevelopmental disorders such as autism, the presence and persistence of complex motor stereotypies (CMS) in otherwise typically developing children (primary CMS) has been well-established. Little, however, is known about the underlying pathophysiology of these unwanted actions. The aim of the present study was to use resting-state functional magnetic resonance imaging to evaluate functional connectivity within frontal–striatal circuits that are essential for goal-directed and habitual activity in children with primary complex motor stereotypies. Functional connectivity between prefrontal cortical and striatal regions, considered essential for developing goal-directed behaviors, was reduced in children with primary CMS compared to their typically developing peers. In contrast, functional connectivity between motor/premotor and striatal regions, critical for developing and regulating habitual behaviors, did not differ between groups. This documented alteration of prefrontal to striatal connectivity could provide the underlying mechanism for the presence and persistence of complex motor stereotypies in otherwise developmentally normal children.

运动刻板印象是有节奏的、重复的、延长的、可预测的和无目的的运动，会随着分心而停止。虽然曾经被认为仅发生在患有神经发育障碍（如自闭症）的儿童中，但在其他典型发育的儿童（原发性 CMS）中存在和持续存在复杂运动刻板印象（CMS）已得到充分证实。然而，人们对这些不良行为的潜在病理生理学知之甚少。本研究的目的是使用静息状态功能磁共振成像来评估额叶-纹状体回路内的功能连通性，这对于具有初级复杂运动刻板印象的儿童的目标导向和习惯性活动至关重要。前额皮质和纹状体区域之间的功能连接，与正常发育的同龄人相比，原发性 CMS 儿童被认为是发展目标导向行为所必需的。相比之下，运动/前运动和纹状体区域之间的功能连接，对于发展和调节习惯性行为至关重要，但各组之间没有差异。这种记录在案的前额叶到纹状体连接的改变可以为其他发育正常的儿童中复杂运动刻板印象的存在和持续提供潜在机制。