猫视皮层细胞对运动光棒刺激的反应特性的定量分析

QUANTITATIVE ANALYSIS OF SOME RESPONSE CHARACTERISTICS OF VISUAL CORTICAL CELLS TO MOVING BAR STIMULI IN THE CAT

数据分析方法的不完善影响了关于细胞视觉反应特性研究结果的可靠性.本工作在分离视觉反应中方向和取向选择性因素的基础上.采用“积分平均”的手段.且将取向选择性理解为“强度随取向的变化率”,得到一种较为准确全面地表现细胞有关反应特性的定量分析法,可以体现出一些以往各方法无法反映出的差别,我们用此方法分析了猫视皮层细胞对运动光棒刺激的反应特性及其相关性.发现取向选择性因素对总反应的贡献较方向选择性大;反应强度,方向选择性和取向选择性三者间存在着弱相关.最优方向、最优取向及方向选择性最强的方向三者间有一定的偏离.

The preciseness of the quantitative expression of visual neuron's response characteristics is lower due to imperfect methods of data analysis, so the other related results are also questionable. In the proceeding paper, we have described a quantitative method for separating directional component from orientational component in a cell's response. Based on this separation, we adopt the concept of 'Variation of response strength with orientation' for the orientational selectivity and the method of 'integration and averaging', and thus developed a general quantitative analysis method to describe the response characteristics.This description has the advantages of completeness and accuracy, and can detect some minor differences which would have been missed with other methods. We have analyzed some response characteristics of visual cortical cells to moving bar stimuli and the correlation calculation between these characteristics were performed. The results show that, (1) the contribution of the orientional component to overall response is larger than that of the directional component. (2) weak correlations exist among the general response level (S) . the directional selectivity strength (D) and the orientational selectivity strength (O). (3) the cell' s perferred direction, preferred orientation and the direction in which the directional tuning is maximum do not necessarily coincide and there are usually some deviations between them.