Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, UK.
Brain Lang. 2013 Nov;127(2):230-40. doi: 10.1016/j.bandl.2013.06.005. Epub 2013 Aug 9.
Primate studies have recently identified the dorsal stream as constituting multiple dissociable pathways associated with a range of specialized cognitive functions. To elucidate the nature and number of dorsal pathways in the human brain, the current study utilized in vivo probabilistic tractography to map the structural connectivity associated with subdivisions of the left supramarginal gyrus (SMG). The left SMG is a prominent region within the dorsal stream, which has recently been parcellated into five structurally-distinct regions which possess a dorsal-ventral (and rostral-caudal) organisation, postulated to reflect areas of functional specialisation. The connectivity patterns reveal a dissociation of the arcuate fasciculus into at least two segregated pathways connecting frontal-parietal-temporal regions. Specifically, the connectivity of the inferior SMG, implicated as an acoustic-motor speech interface, is carried by an inner/ventro-dorsal arc of fibres, whilst the pathways of the posterior superior SMG, implicated in object use and cognitive control, forms a parallel outer/dorso-dorsal crescent.
灵长类动物研究最近发现，背侧流由与一系列专门认知功能相关的多个可分离的途径组成。为了阐明人类大脑中背侧通路的性质和数量，本研究利用体内概率轨迹描绘技术来描绘与左侧缘上回（SMG）细分相关的结构连通性。左侧 SMG 是背侧流中的一个突出区域，最近已被划分成五个具有背腹（和前后）组织的结构不同的区域，据推测反映了功能专业化的区域。连接模式揭示了弓状束（arcuate fasciculus）至少分为两个连接额顶颞区域的分离途径。具体而言，与语音接口相关的下侧 SMG 的连接由纤维的内/腹侧-背侧弧承载，而与物体使用和认知控制相关的后上 SMG 的途径则形成平行的外/背侧-背侧新月形。
