Yu S, Wang Y, Li X, Zhou Y, Leventhal A G
Department of Neurobiology and Biophysics, University of Science and Technology of China, Hefei, Anhui 230027, PR China.
Neuroscience. 2006 Jul 7;140(3):1023-9. doi: 10.1016/j.neuroscience.2006.01.015. Epub 2006 May 6.
The receptive field properties of striate cortical (V1) cells degrade in senescent macaque monkeys. We have now carried out extracellular single unit studies of the receptive field properties of cells in extrastriate visual cortex (area V2) in very old rhesus (Macaca mulatta) monkeys. This study provides evidence that both the orientation and direction selectivities of V2 cells in old monkeys degrade significantly. Decreased selectivity is accompanied by increased visually driven and spontaneous responses. As a result, V2 cells in old animals exhibit markedly decreased signal-to-noise ratios. A significant degradation of neural function in extrastriate cortex may underlie the declines in higher order visual function that accompany normal aging.
在衰老的猕猴中，纹状皮层（V1）细胞的感受野特性会退化。我们现在对非常年老的恒河猴（猕猴属）视皮层外区（V2区）细胞的感受野特性进行了细胞外单单位研究。这项研究提供了证据，表明老年猕猴V2区细胞的方向选择性和运动方向选择性均显著退化。选择性降低伴随着视觉驱动反应和自发反应的增加。结果，老年动物的V2区细胞信噪比明显降低。视皮层外区神经功能的显著退化可能是正常衰老过程中高阶视觉功能下降的基础。
