Laboratoire de Physiologie de la Perception et de l'Action, College-de-France, CNRS UMR 7152, 11 Place Marcelin Berthelot, 75005 Paris, France.
Front Biosci (Landmark Ed). 2010 Jan 1;15(2):681-707. doi: 10.2741/3640.
The question of whether neural synchrony may be preserved in adult mammalian visual cortex despite abnormal postnatal visual experience was investigated by combining anatomical and computational approaches. Single callosal axons in visual cortex of early monocularly deprived (MD) adult cats were labeled anterogradely with biocytin in vivo and reconstructed in 3D. Spike propagation was then orthodromically simulated within each of these axons with NEURON software. Data were systematically compared to those previously obtained in normally reared (NR) adult cats with comparable approaches. The architecture of the callosal axons in MD animals differed significantly from the NR group, with longer branches and first nodes located deeper below the cortex. But, surprisingly, simulation of spike propagation demonstrated that transmission latencies of most spikes remained inferior to 2 ms, like the NR group. These results indicate that synchrony of neural activity may be preserved in adult visual cortex despite abnormal postnatal visual experience. According to the temporal binding hypothesis, this also indicates that the necessary timing for visual perception is present despite anatomical abnormalities in visual cortex.
尽管在后天的视觉经验异常的情况下，成年哺乳动物的视觉皮层中的神经同步性是否能够保持，这是一个问题。研究人员通过结合解剖学和计算方法来研究这个问题。在早期单眼剥夺（MD）的成年猫的视觉皮层中，用生物胞素将单个胼胝体轴突活体标记，并在 3D 中重建。然后，使用 NEURON 软件在每个轴突中进行正向模拟。数据与以前用类似方法在正常饲养的（NR）成年猫中获得的数据进行了系统比较。MD 动物的胼胝体轴突的结构与 NR 组有显著差异，分支更长，第一个节点位于皮层下方更深的位置。但是，令人惊讶的是，尖峰传播的模拟表明，大多数尖峰的传输延迟仍然低于 2ms，与 NR 组相似。这些结果表明，尽管存在后天的视觉经验异常，成年视觉皮层中的神经活动同步性仍可能保持。根据时间绑定假说，这也表明尽管视觉皮层存在解剖学异常，但仍存在用于视觉感知的必要时间。
