Data from: Emergence of transformation-tolerant representations of visual objects in rat lateral extrastriate cortex

Rodents are emerging as increasingly popular models of visual functions. Yet, evidence that rodent visual cortex is capable of advanced visual processing, such as object recognition, is limited. Here we investigate how neurons located along the progression of extrastriate areas that, in the rat brain, run laterally to primary visual cortex, encode object information. We found a progressive functional specialization of neural responses along these areas, with: (1) a sharp reduction of the amount of low-level, energy-related visual information encoded by neuronal firing; and (2) a substantial increase in the ability of both single neurons and neuronal populations to support discrimination of visual objects under identity-preserving transformations (e.g., position and size changes). These findings strongly argue for the existence of a rat object-processing pathway, and point to the rodents as promising models to dissect the neuronal circuitry underlying transformation-tolerant recognition of visual objects.

啮齿类动物正日益成为视觉功能研究中备受青睐的动物模型。然而，能够证明啮齿类动物视觉皮层具备物体识别等高级视觉加工能力的相关证据仍较为匮乏。本研究针对大鼠脑中沿初级视觉皮层（primary visual cortex）向外侧延伸的纹外皮层区域（extrastriate areas）内的神经元展开探究，解析其编码物体信息的机制。研究发现，沿此类纹外皮层区域，神经反应呈现出渐进式的功能特化：一是神经元放电所编码的低水平、与能量相关的视觉信息出现显著缩减；二是单个神经元与神经元集群在耐受保持物体同一性的变换（identity-preserving transformations，如位置与大小变化）条件下完成视觉物体辨别的能力均大幅提升。上述研究结果有力佐证了大鼠体内存在物体加工通路，同时也表明啮齿类动物是剖析耐受变换的视觉物体识别背后神经环路的极具潜力的实验模型。