Bi Yanchao, Han Zaizhu, Zhong Suyu, Ma Yujun, Gong Gaolang, Huang Ruiwang, Song Luping, Fang Yuxing, He Yong, Caramazza Alfonso
State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China.
State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China,
J Neurosci. 2015 Apr 29;35(17):6822-35. doi: 10.1523/JNEUROSCI.3709-14.2015.
The ability to recognize, create, and use complex tools is a milestone in human evolution. Widely distributed brain regions in parietal, frontal, and temporal cortices have been implicated in using and understanding tools, but the roles of their anatomical connections in supporting tool use and tool conceptual behaviors are unclear. Using deterministic fiber tracking in healthy participants, we first examined how 14 cortical regions that are consistently activated by tool processing are connected by white matter (WM) tracts. The relationship between the integrity of each of the 33 obtained tracts and tool processing deficits across 86 brain-damaged patients was investigated. WM tract integrity was measured with both lesion percentage (structural imaging) and mean fractional anisotropy (FA) values (diffusion imaging). Behavioral abilities were assessed by a tool use task, a range of conceptual tasks, and control tasks. We found that three left hemisphere tracts connecting frontoparietal and intrafrontal areas overlapping with left superior longitudinal fasciculus are crucial for tool use such that larger lesion and lower mean FA values on these tracts were associated with more severe tool use deficits. These tracts and five additional left hemisphere tracts connecting frontal and temporal/parietal regions, mainly overlapping with left superior longitudinal fasciculus, inferior frontooccipital fasciculus, uncinate fasciculus, and anterior thalamic radiation, are crucial for tool concept processing. Largely consistent results were also obtained using voxel-based symptom mapping analyses. Our results revealed the WM structural networks that support the use and conceptual understanding of tools, providing evidence for the anatomical skeleton of the tool knowledge network.
识别、制造和使用复杂工具的能力是人类进化的一个里程碑。顶叶、额叶和颞叶皮质中广泛分布的脑区与工具的使用和理解有关，但其解剖连接在支持工具使用和工具概念行为中的作用尚不清楚。我们首先在健康参与者中使用确定性纤维追踪技术，研究了14个在工具处理过程中持续被激活的皮质区域是如何通过白质（WM）束连接的。我们调查了86名脑损伤患者中获得的33条束的完整性与工具处理缺陷之间的关系。通过病变百分比（结构成像）和平均分数各向异性（FA）值（扩散成像）来测量WM束的完整性。通过工具使用任务、一系列概念任务和对照任务来评估行为能力。我们发现，连接额顶叶和额内区域且与左上纵束重叠的三条左半球束对工具使用至关重要，这些束上较大的病变和较低的平均FA值与更严重的工具使用缺陷相关。这些束以及另外五条连接额叶和颞叶/顶叶区域的左半球束，主要与左上纵束、额枕下束、钩束和丘脑前辐射重叠，对工具概念处理至关重要。使用基于体素的症状映射分析也获得了大致一致的结果。我们的结果揭示了支持工具使用和概念理解的WM结构网络，为工具知识网络的解剖学框架提供了证据。
