Tootell R B, Hadjikhani N, Hall E K, Marrett S, Vanduffel W, Vaughan J T, Dale A M
Nuclear Magnetic Resonance Center, Massachusetts General Hospital, Charlestown, 02129, USA.
Neuron. 1998 Dec;21(6):1409-22. doi: 10.1016/s0896-6273(00)80659-5.
We used high-field (3T) functional magnetic resonance imaging (fMRI) to label cortical activity due to visual spatial attention, relative to flattened cortical maps of the retinotopy and visual areas from the same human subjects. In the main task, the visual stimulus remained constant, but covert visual spatial attention was varied in both location and load. In each of the extrastriate retinotopic areas, we found MR increases at the representations of the attended target. Similar but smaller increases were found in V1. Decreased MR levels were found in the same cortical locations when attention was directed at retinotopically different locations. In and surrounding area MT+, MR increases were lateralized but not otherwise retinotopic. At the representation of eccentricities central to that of the attended targets, prominent MR decreases occurred during spatial attention.
我们使用高场（3T）功能磁共振成像（fMRI），相对于同一人类受试者视网膜拓扑和视觉区域的扁平皮质图谱，标记由视觉空间注意力引起的皮质活动。在主要任务中，视觉刺激保持不变，但隐蔽的视觉空间注意力在位置和负荷上有所变化。在每个纹外视网膜拓扑区域，我们发现参与的目标表征处的磁共振信号增强。在V1中发现了类似但较小的增强。当注意力指向视网膜拓扑上不同的位置时，在相同的皮质位置发现磁共振水平降低。在MT +区域及其周围，磁共振信号增强呈侧向化，但在其他方面不是视网膜拓扑性的。在参与目标的偏心率中心的表征处，在空间注意力期间出现了明显的磁共振信号降低。
