What Role Does "Elongation" Play in "Tool-Specific" Activation and Connectivity in the Dorsal and Ventral Visual Streams?
What Role Does "Elongation" Play in "Tool-Specific" Activation and Connectivity in the Dorsal and Ventral Visual Streams?
复制标题
DOI：
10.1093/cercor/bhx017
复制
发表时间：
2018-04-01
期刊：
影响因子：
3.7
通讯作者：
Goodale, Melvyn A.
中科院分区：
文献类型：
--
作者：
Chen, Juan;Snow, Jacqueline C.;Goodale, Melvyn A.
工具图像比非工具图像在左侧网络中诱导更强的激活，左侧网络包括与工具识别有关的腹侧流区域和与工具操作有关的背侧流区域。然而，重要的是，可抓取工具往往是细长的，而不是粗短的，因此在某些区域的工具选择响应可能在某种程度上反映了对伸长的敏感性，而不是“工具性”本身。利用功能性磁共振成像，我们研究了延伸在驱动两种流的工具特异性激活及其相互联系中的作用。我们发现，在一些“工具选择性”区域，工具度和延伸度编码共存，而在其他区域，延伸度和工具度编码独立。心理生理相互作用分析显示，工具性，而不是伸长性，对腹侧和背侧流之间的连接有很强的调节作用。动态因果模型显示，观察工具（无论是细长的还是短的）增加了从腹流到背流工具选择区域的连通性，但只有观察细长的工具增加了这些区域之间的相互连通性。总的来说，这些数据揭示了工具性和延伸率如何影响工具网络的激活和连通性，并有助于解决最近关于“工具性”与延伸率在驱动背侧流“工具选择”区域中的相对贡献的争议。
Images of tools induce stronger activation than images of nontools in a left-lateralized network that includes ventral-stream areas implicated in tool identification and dorsal-stream areas implicated in tool manipulation. Importantly, however, graspable tools tend to be elongated rather than stubby, and so the tool-selective responses in some of these areas may, to some extent, reflect sensitivity to elongation rather than "toolness" per se. Using functional magnetic resonance imaging, we investigated the role of elongation in driving tool-specific activation in the 2 streams and their interconnections. We showed that in some "tool-selective" areas, the coding of toolness and elongation coexisted, but in others, elongation and toolness were coded independently. Psychophysiological interaction analysis revealed that toolness, but not elongation, had a strong modulation of the connectivity between the ventral and dorsal streams. Dynamic causal modeling revealed that viewing tools (either elongated or stubby) increased the connectivity from the ventral- to the dorsal-stream tool-selective areas, but only viewing elongated tools increased the reciprocal connectivity between these areas. Overall, these data disentangle how toolness and elongation affect the activation and connectivity of the tool network and help to resolve recent controversies regarding the relative contribution of "toolness" versus elongation in driving dorsal-stream "tool-selective" areas.