Viher Petra V, Abdulkadir Ahmed, Savadijev Peter, Stegmayer Katharina, Kubicki Marek, Makris Nikos, Karmacharya Sarina, Federspiel Andrea, Bohlhalter Stephan, Vanbellingen Tim, Müri René, Wiest Roland, Strik Werner, Walther Sebastian
Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland; Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, USA.
University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland.
Cortex. 2020 Nov;132:322-333. doi: 10.1016/j.cortex.2020.05.023. Epub 2020 Aug 27.
Hand gestures are an integral part of social interactions and communication. Several imaging studies in healthy subjects and lesion studies in patients with apraxia suggest the praxis network for gesture production, involving mainly left inferior frontal, posterior parietal and temporal regions. However, little is known about the structural connectivity underlying gesture production. We recruited 41 healthy participants and 39 patients with schizophrenia. All participants performed a gesture production test, the Test of Upper Limb Apraxia, and underwent diffusion tensor imaging. We hypothesized that gesture production is associated with structural network connectivity as well as with tract integrity. We defined the praxis network as an undirected graph comprised of 13 bilateral regions of interest and derived measures of local and global structural connectivity and tract integrity from Finsler geometry. We found an association of gesture deficit with reduced global and local efficiency of the praxis network. Furthermore, reduced tract integrity, for example in the superior longitudinal fascicle, arcuate fascicle or corpus callosum were related to gesture deficits. Our findings contribute to the understanding of structural correlates of gesture production as they first present diffusion tensor imaging data in a combined sample of healthy subjects and a patient cohort with gestural deficits.
手势是社交互动和交流中不可或缺的一部分。针对健康受试者的多项成像研究以及对失用症患者的病灶研究表明，手势产生的实践网络主要涉及左额叶下部、顶叶后部和颞叶区域。然而，对于手势产生背后的结构连通性却知之甚少。我们招募了41名健康参与者和39名精神分裂症患者。所有参与者都进行了一项手势产生测试，即上肢失用症测试，并接受了扩散张量成像。我们假设手势产生与结构网络连通性以及纤维束完整性有关。我们将实践网络定义为由13个双侧感兴趣区域组成的无向图，并从芬斯勒几何学中得出局部和全局结构连通性以及纤维束完整性的测量值。我们发现手势缺陷与实践网络的全局和局部效率降低有关。此外，纤维束完整性降低，例如在 superior longitudinal fascicle（上纵束）、arcuate fascicle（弓状束）或胼胝体中，与手势缺陷有关。我们的研究结果有助于理解手势产生的结构相关性，因为它们首次在健康受试者和有手势缺陷的患者队列的联合样本中呈现了扩散张量成像数据。
