Combined activation and deactivation of visual cortex during tactile sensory processing
Combined activation and deactivation of visual cortex during tactile sensory processing
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DOI：
10.1152/jn.00806.2006
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发表时间：
2007-02-01
影响因子：
2.5
通讯作者：
Somers, David C.
中科院分区：
文献类型：
--
作者：
Merabet, Lotfi B.;Swisher, Jascha D.;Somers, David C.
枕叶皮层参与感觉处理并不仅仅局限于视觉形式。触觉处理已被证明是调节高阶视觉和多感觉整合领域的视力以及视觉剥夺的主题，然而，早期视觉皮层区域的参与程度仍然不清楚。为了研究这个问题，我们采用功能磁共振成像在正常视力，短暂蒙眼的科目具有明确的视觉边界，因为他们的触觉探索和评级凸起的圆点图案。触觉任务的表现导致显着激活初级视觉皮层（V1）和纹外皮质区V2，V3，V3A，和hV4的失活与更大的失活在背侧亚区和更高的视觉区。这些结果表明，触觉处理影响枕叶皮层通过两个不同的途径：抑制性自上而下的途径下降，通过视觉皮层层次结构和兴奋性途径产生的视觉皮层层次结构外，直接驱动V1区。
The involvement of occipital cortex in sensory processing is not restricted solely to the visual modality. Tactile processing has been shown to modulate higher-order visual and multisensory integration areas in sighted as well as visually deprived subjects; however, the extent of involvement of early visual cortical areas remains unclear. To investigate this issue, we employed functional magnetic resonance imaging in normally sighted, briefly blindfolded subjects with well-defined visuotopic borders as they tactually explored and rated raised-dot patterns. Tactile task performance resulted in significant activation in primary visual cortex (V1) and deactivation of extrastriate cortical regions V2, V3, V3A, and hV4 with greater deactivation in dorsal subregions and higher visual areas. These results suggest that tactile processing affects occipital cortex via two distinct pathways: a suppressive top-down pathway descending through the visual cortical hierarchy and an excitatory pathway arising from outside the visual cortical hierarchy that drives area V1 directly.