Gonzalez Francisco, Romero Maria C, Castro Adrian F, Bermudez Maria A, Perez Rogelio
Department of Physiology, School of Medicine, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
Eur J Neurosci. 2007 Apr;25(8):2536-46. doi: 10.1111/j.1460-9568.2007.05507.x.
We are able to judge the direction of movement and orientation of objects because they have contrast-defined edges. However, we are also able to perceive the orientation and direction of movement of stereobars made of random dot stereograms in the absence of contrast-defined edges. We recorded 207 disparity-sensitive cells from visual areas V1 and V2 of two Macaca mulatta monkeys while performing an attentive fixation task. Luminance defined bars and random-dot stereo-defined bars were used to assess direction and orientation selectivity of these cells. Orientation and direction preference for luminance bars and for stereobars showed a statistically significant relationship (r=0.83, P<0.01 for direction; r=0.63, P<0.01 for orientation). However, disparity-sensitive cells from these areas seem to be more sensitive to luminance than to stereobars regarding orientation and direction of movement. Similar results were obtained when the two areas were considered separately. Our results show that cells in areas V1 and V2 of the monkey visual cortex are able to detect the orientation and direction of movement of stereobars in a manner similar to those of luminance-defined bars. This finding is relevant because to detect the direction and orientation of stereobars a comparison between left and right eye inputs is required.
我们能够判断物体的运动方向和取向，因为它们具有对比度定义的边缘。然而，在没有对比度定义的边缘的情况下，我们也能够感知由随机点立体图制成的立体棒的取向和运动方向。在两只恒河猴执行注意力集中的注视任务时，我们从视觉区域V1和V2记录了207个视差敏感细胞。使用亮度定义的棒和随机点立体定义的棒来评估这些细胞的方向和取向选择性。亮度棒和立体棒的取向和方向偏好显示出统计学上的显著关系（方向：r = 0.83，P <0.01；取向：r = 0.63，P <0.01）。然而，就运动的取向和方向而言，来自这些区域的视差敏感细胞似乎对亮度比对立体棒更敏感。当分别考虑这两个区域时，也获得了类似的结果。我们的结果表明，猴子视觉皮层V1和V2区域的细胞能够以类似于亮度定义的棒的方式检测立体棒的取向和运动方向。这一发现很重要，因为要检测立体棒的方向和取向，需要比较左右眼的输入。
