■最大握力,衡量一个人的手在挤压物体时可以产生多大的力,可能是理解运动任务中潜在神经生物学差异的有效方法。自闭症患者的抓地力可能因其独特的发展轨迹而受到特别关注。虽然在成人人群中发现了自闭症-大脑关系的特定差异,在孤独症和非孤独症人群中,抓力-大脑关系的这种差异可能存在于较早的年龄,此时抓力能力在行为上相似.Further,这种神经差异可能会导致青春期诊断群体抓地力差异的出现。本研究试图检验这种可能性,同时还检查握力是否可以阐明自闭症中常见的表型异质性的神经运动来源。
■使用高分辨率,多壳扩散,和定量R1弛豫测量成像,这项研究检查了本体感觉输入的关键感觉运动相关白质通路的变化,横向抓握,皮质-小脑,在68名自闭症儿童和70名非自闭症(神经典型)儿童(6-11岁)中,皮质脊髓网络与握力的个体差异相关.
■在两组中,结果表明,较强的握力与较高的本体感受输入相关,横向抓握,和皮质脊髓(但不是皮质小脑修饰)分数各向异性和R1,间接测量与更强的微结构相干性和增加的髓鞘形成相一致。没有观察到这些握力-大脑关系的诊断组差异,但是自闭症组表现出更多的变异性,尤其是在皮质-小脑修饰指数方面。对自闭症患者体内变异性的检查显示,注意力缺陷/多动障碍(ADHD)的特征缓和了握力与横向抓握网络和皮质的运动前主要运动道中的分数各向异性和R1弛豫测量之间的关系。小脑网络束。具体来说,在多动症特征升高的自闭症儿童中(自闭症组的60%),更强的握力与更高的分数各向异性和小脑修饰网络的R1(更强的微结构相干性和更多的髓鞘)有关,而在多动症特征减少的自闭症儿童中观察到相反的关系。
■一起,这项工作表明,尽管在学龄期自闭症和非自闭症儿童中,握力的基本要素相似,自闭症儿童握力的神经机制可能还取决于ADHD特征的存在。具体来说,更强,小脑修饰网络的更连贯的连接,它被认为在精炼和优化电机命令方面发挥作用,可能会导致更多的多动症特征的儿童更强的抓地力,多动症特征较少的儿童抓地力较弱,非自闭症儿童的抓地力没有差异。虽然需要未来的研究来了解这些发现是否扩展到除了握力之外的其他运动任务,这些结果对于理解自闭症儿童神经运动控制的生物学基础具有重要意义,并强调在评估自闭症患者的脑行为关系时评估共现状况的重要性.
UNASSIGNED: Maximal grip strength, a measure of how much force a person\'s hand can generate when squeezing an object, may be an effective method for understanding potential neurobiological differences during motor tasks. Grip strength in autistic individuals may be of particular interest due to its unique developmental trajectory. While autism-specific differences in grip-brain relationships have been found in adult populations, it is possible that such differences in grip-brain relationships may be present at earlier ages when grip strength is behaviorally similar in autistic and non-autistic groups. Further, such neural differences may lead to the later emergence of diagnostic-group grip differences in adolescence. The present study sought to examine this possibility, while also examining if grip strength could elucidate the neuro-motor sources of phenotypic heterogeneity commonly observed within autism.
UNASSIGNED: Using high resolution, multi-shell diffusion, and quantitative R1 relaxometry imaging, this study examined how variations in key sensorimotor-related white matter pathways of the proprioception input, lateral grasping, cortico-cerebellar, and corticospinal networks were associated with individual variations in grip strength in 68 autistic children and 70 non-autistic (neurotypical) children (6-11 years-old).
UNASSIGNED: In both groups, results indicated that stronger grip strength was associated with higher proprioceptive input, lateral grasping, and corticospinal (but not cortico-cerebellar modification) fractional anisotropy and R1, indirect measures concordant with stronger microstructural coherence and increased myelination. Diagnostic group differences in these grip-brain relationships were not observed, but the autistic group exhibited more variability particularly in the cortico-cerebellar modification indices. An examination into the variability within the autistic group revealed that attention-deficit/hyperactivity disorder (ADHD) features moderated the relationships between grip strength and both fractional anisotropy and R1 relaxometry in the premotor-primary motor tract of the lateral grasping network and the cortico-cerebellar network tracts. Specifically, in autistic children with elevated ADHD features (60% of the autistic group) stronger grip strength was related to higher fractional anisotropy and R1 of the cerebellar modification network (stronger microstructural coherence and more myelin), whereas the opposite relationship was observed in autistic children with reduced ADHD features.
UNASSIGNED: Together, this work suggests that while the foundational elements of grip strength are similar across school-aged autistic and non-autistic children, neural mechanisms of grip strength within autistic children may additionally depend on the presence of ADHD features. Specifically, stronger, more coherent connections of the cerebellar modification network, which is thought to play a role in refining and optimizing motor commands, may lead to stronger grip in children with more ADHD features, weaker grip in children with fewer ADHD features, and no difference in grip in non-autistic children. While future research is needed to understand if these findings extend to other motor tasks beyond grip strength, these results have implications for understanding the biological basis of neuromotor control in autistic children and emphasize the importance of assessing co-occurring conditions when evaluating brain-behavior relationships in autism.