Zhu Wei, Xing Dajun, Shelley Michael, Shapley Robert
Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, NY 10012, United States.
Vision Res. 2010 Oct 28;50(22):2261-73. doi: 10.1016/j.visres.2010.01.007. Epub 2010 Jan 14.
We addressed how spatial frequency and orientation selectivity coexist and co-vary in Macaque primary visual cortex (V1) by simulating cortical layer 4Cα of V1 with a large-scale network model and then comparing the model's behavior with a population of cells we recorded in layer 4Cα. We compared the distributions of orientation and spatial frequency selectivity, as well as the correlation between the two, in the model with what we observed in the 4Cα population. We found that (1) in the model, both spatial frequency and orientation selectivity of neuronal firing are greater and more diverse than the LGN inputs to model neurons; (2) orientation and spatial frequency selectivity co-vary in the model in a way very similar to what we observed in layer 4Cα neurons; (3) in the model, orientation and spatial frequency selectivity co-vary because of intra-cortical inhibition. The results suggest that cortical inhibition provides a common mechanism for selectivity in multiple dimensions.
我们通过用大规模网络模型模拟猕猴初级视觉皮层（V1）的第4Cα层，然后将模型行为与我们在第4Cα层记录的一群细胞进行比较，探讨了空间频率和方向选择性在V1中如何共存和共同变化。我们将模型中方向和空间频率选择性的分布以及两者之间的相关性与我们在4Cα群体中观察到的情况进行了比较。我们发现：（1）在模型中，神经元放电的空间频率和方向选择性都比模型神经元的外侧膝状体输入更大且更多样化；（2）模型中方向和空间频率选择性的共同变化方式与我们在第4Cα层神经元中观察到的非常相似；（3）在模型中，方向和空间频率选择性因皮层内抑制而共同变化。结果表明，皮层抑制为多维度选择性提供了一种共同机制。
