Individuals with autism spectrum disorder (ASD) often have difficulty with coordinated fine motor skills, but the degree of difficulty significantly varies from person to person. To elucidate the cause of this diversity, we monitored brain activity during fine movement tasks (tying bowknots) by near-infrared spectroscopy in 17 adults with ASD and 18 adults with typical development matched for age, gender, and intelligence quotient (IQ). We also examined the relationship between brain activation and developmental characteristics, including ASD severity, using the Autism-Spectrum Quotient and the Multi-dimensional Scale for Pervasive Developmental Disorder and Attention-Deficit/Hyperactivity Disorder. Although participants in the ASD group did not show significant clumsiness, their right prefrontal cortexes were relatively less activated, particularly in individuals with poor social skills and inattention. Our study indicates that individuals with ASD traits may use different strategies when performing fine movements; that is, they less use the brain areas responsible for processing visual image or planning behaviors.

患有自闭症谱系障碍 (ASD) 的个体通常难以协调精细运动技能，但难度因人而异。为了阐明这种多样性的原因，我们通过近红外光谱监测了 17 名患有 ASD 的成年人和 18 名具有与年龄、性别和智商 (IQ) 相匹配的典型发育的成年人在精细运动任务（系蝴蝶结）期间的大脑活动。我们还使用自闭症谱商和广泛性发育障碍和注意力缺陷/多动障碍的多维量表检查了大脑激活与发育特征（包括 ASD 严重程度）之间的关系。尽管 ASD 组的参与者没有表现出明显的笨拙，但他们的右前额叶皮层相对较少被激活，尤其是社交能力差和注意力不集中的人。我们的研究表明，具有 ASD 特征的个体在进行精细动作时可能会使用不同的策略；也就是说，他们较少使用负责处理视觉图像或规划行为的大脑区域。