Department of Psychology and Neurobiology, University of California Los Angeles, Los Angeles, California, United States of America.
PLoS One. 2007 Feb 28;2(2):e251. doi: 10.1371/journal.pone.0000251.
The basic structure of receptive fields and functional maps in primary visual cortex is established without exposure to normal sensory experience and before the onset of the critical period. How the brain wires these circuits in the early stages of development remains unknown. Possible explanations include activity-dependent mechanisms driven by spontaneous activity in the retina and thalamus, and molecular guidance orchestrating thalamo-cortical connections on a fine spatial scale. Here I propose an alternative hypothesis: the blueprint for receptive fields, feature maps, and their inter-relationships may reside in the layout of the retinal ganglion cell mosaics along with a simple statistical connectivity scheme dictating the wiring between thalamus and cortex. The model is shown to account for a number of experimental findings, including the relationship between retinotopy, orientation maps, spatial frequency maps and cytochrome oxidase patches. The theory's simplicity, explanatory and predictive power makes it a serious candidate for the origin of the functional architecture of primary visual cortex.
初级视觉皮层的感受野和功能图谱的基本结构是在没有正常感觉体验和关键期开始之前建立的。在发育的早期阶段，大脑如何构建这些回路仍然未知。可能的解释包括由视网膜和丘脑的自发活动驱动的活动依赖性机制，以及分子指导在精细的空间尺度上协调丘脑皮质连接的机制。在这里，我提出了一个替代假设：感受野、特征图谱及其相互关系的蓝图可能存在于沿着视网膜神经节细胞镶嵌图的布局中，以及一个简单的统计连接方案决定了丘脑和皮层之间的连接。该模型被证明可以解释许多实验结果，包括视网膜映射、方向图、空间频率图和细胞色素氧化酶斑块之间的关系。该理论的简单性、解释力和预测能力使其成为初级视觉皮层功能结构起源的一个重要候选者。
