Vision Research Laboratory, Center for Brain Science Research and School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai 200433, China.
Vision Research Laboratory, Center for Brain Science Research and School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai 200433, China.
Neuroscience. 2018 May 21;379:77-92. doi: 10.1016/j.neuroscience.2018.03.005. Epub 2018 Mar 15.
Cortices are non-uniform in their capacity for adaptive changes. In cat area 17, pinwheel centers of the orientation map demonstrated much greater selectivity shifts after the orientation adaptation than the iso-orientation domains (Dragoi et al., 2001a). However, whether this heterogeneity exists in other visual cortical regions remains unclear. Similar to area 17, area 21a neurons in cats are well known to be functionally clustered according to their orientation preference in iso-orientation domains that converge at pinwheel centers but with a higher pinwheel density (Huang et al., 2006). In this study, we simultaneously measured the adaptation effects on the orientation maps in area 17 and area 21a of anesthetized cats by intrinsic signal optical imaging. We found that in area 21a, the adaptation-induced selectivity shifts were significantly larger at pinwheel centers, similar to the findings in area 17. However, at either pinwheel centers or iso-orientation domains, the selectivity shifts in area 21a were all consistently greater than those in area 17, even though the heterogeneity in the orientation distribution was similar in the two areas. More importantly, in our short-term adaptation protocol, orientation adaptation in area 17 resulted in mostly repulsive shifts at the pinwheel center region, while in area 21a, it induced both repulsive and attractive effects. These results suggest that both common and distinct strategies exist for orientation adaptation across cortices and sub-regions.
皮质在适应变化的能力上是不均匀的。在猫的大脑 17 区，朝向图的扇区中心在朝向适应后表现出比同朝向域更大的选择性变化（Dragoi 等人，2001a）。然而，这种异质性是否存在于其他视觉皮质区域尚不清楚。与 17 区相似，猫的 21a 区神经元以其在同朝向域中的朝向偏好为特征，这些神经元在扇区中心汇聚，但扇区密度更高（Huang 等人，2006）。在这项研究中，我们通过内源信号光学成像同时测量了麻醉猫大脑 17 区和 21a 区的朝向图的适应效应。我们发现，在 21a 区，扇区中心的适应诱导选择性变化明显更大，与 17 区的发现相似。然而，无论是在扇区中心还是同朝向域，21a 区的选择性变化都始终大于 17 区，尽管这两个区域的朝向分布的异质性相似。更重要的是，在我们的短期适应方案中，17 区的朝向适应导致扇区中心区域的排斥性变化，而在 21a 区，它既引起排斥性又引起吸引性效应。这些结果表明，在皮质和亚区之间存在共同和独特的朝向适应策略。
