Human MST but not MT responds to tactile stimulation
Human MST but not MT responds to tactile stimulation
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DOI：
10.1523/jneurosci.0754-07.2007
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发表时间：
2007-08-01
影响因子：
5.3
通讯作者：
Ro, Tony
中科院分区：
文献类型：
--
作者：
Beauchamp, Michael S.;Yasar, Nafi E.;Ro, Tony
以往关于视觉MT/V5区触觉反应的研究多采用复杂的刺激，如用刷子抚摸手臂，这些复杂的运动刺激很可能诱发视觉运动的表象，而视觉运动表象是MT的一种强有力的激活剂。在以前的报告中被描述为“MT”的区域由至少两个不同的皮层区域MT和MST组成。使用功能性磁共振成像，我们分别定位人类MT和MST和测量他们的反应，振动触觉刺激不太可能引起视觉运动的图像。在MST中观察到强烈的振动触觉反应，但在MT中没有。MST的振动触觉反应约为视觉运动反应的一半，与先前报道的对触觉刺激做出反应的另一个视觉区域枕外侧复合体不同。为了检查躯体位置组织，我们分别刺激左右手和脚。在MST中没有观察到手和脚反应之间的空间分离。MST的平均反应曲线与躯体感觉皮层相似，对对侧手有强烈的偏好。这些结果提供了证据的存在体感反应MST，但不是MT，独立的视觉运动的图像。
Previous reports of tactile responses in human visual area MT/V5 have used complex stimuli, such as a brush stroking the arm. These complex moving stimuli are likely to induce imagery of visual motion, which is known to be a powerful activator of MT. The area described as "MT" in previous reports consists of at least two distinct cortical areas, MT and MST. Using functional magnetic resonance imaging, we separately localized human MT and MST and measured their response to vibrotactile stimuli unlikely to induce imagery of visual motion. Strong vibrotactile responses were observed in MST but not in MT. Vibrotactile responses in MST were approximately one-half as large as the response to visual motion and were distinct from those in another visual area previously reported to respond to tactile stimulation, the lateral occipital complex. To examine somatotopic organization, we separately stimulated the left and right hand and foot. No spatial segregation between hand and foot responses was observed in MST. The average response profile of MST was similar to that of somatosensory cortex, with a strong preference for the contralateral hand. These results offer evidence for the existence of somatosensory responses in MST, but not MT, independent of imagery of visual motion.