Real and illusory contour processing in area VI of the primate: a cortical balancing act
Real and illusory contour processing in area VI of the primate: a cortical balancing act
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DOI：
10.1093/cercor/11.7.648
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发表时间：
2001-07-01
期刊：
影响因子：
3.7
通讯作者：
Roe, AW
中科院分区：
文献类型：
--
作者：
Ramsden, BM;Hung, CP;Roe, AW
众所周知，灵长类动物V2区（第二视觉区）的神经元可以发出错觉轮廓的方向信号。V1区（初级视皮层）是否可以发出错觉轮廓定向信号，这一点更有争议。虽然一些电生理学研究已经排除了V1中的错觉信号，但其他报告表明VI显示出一些错觉特异性反应。在这里，使用光学成像和单单位电生理学，我们报告说，灵长类动物V1没有显示出特定的方向响应的“邻接线光栅”虚幻的轮廓。然而，这种响应并不表示传统意义上的虚幻轮廓。相反，我们发现，虚幻的轮廓刺激导致激活地图，适当的：减去真实的线信号后，与真实的方向图成反比。因此，虚幻的轮廓取向在W中被否定地信号化或去强调。这种“激活逆转”是稳健的，不仅仅是由于线末端的存在，不依赖于诱导物取向，也不是由于V1细胞的线末端刺激的精确位置。这些数据为以前明显矛盾的实验结果提供了解决方案。我们认为，V1中虚幻轮廓方向的去强调可能是轮廓同一性的重要信号，并且可能与V2中的虚幻信号一起为虚幻轮廓表示提供唯一的签名。
It is known that neurons in area V2 (the second visual area) can signal the orientation of illusory contours in the primate. Whether area V1 (primary visual cortex) can signal illusory contour orientation is more controversial. While some electrophysiology studies have ruled out illusory signaling in V1, other reports suggest that VI shows some illusory-specific response. Here, using optical imaging and single unit electrophysiology, we report that primate V1 does show an orientation-specific response to the 'abutting line grating' illusory contour. However, this response does not signal an illusory contour in the conventional sense. Rather, we find that illusory contour stimulation leads to an activation map that, after appropriate: subtraction of real line signal, is inversely related to the real orientation map. The illusory contour orientation is thus negatively signaled or de-emphasized in W. This 'activation reversal' is robust is not due merely to presence of line ends, is not dependent on inducer orientation, and is not due to precise position of line end stimulation of V1 cells. These data suggest a resolution for previous apparently contradictory experimental findings. We propose that the de-emphasis, of illusory contour orientation in V1 may he an important signal of contour identity and may, together with illusory signal from V2, provide a unique signature for illusory contour representation.