Menz Michael D, Freeman Ralph D
Group in Vision Science, School of Optometry, and the Helen Wills Neuroscience Institute, University of California, Berkeley, 94720-2020, USA.
Nat Neurosci. 2003 Jan;6(1):59-65. doi: 10.1038/nn986.
For binocular animals viewing a three-dimensional scene, the left and right eyes receive slightly different information, and the brain uses this 'binocular disparity' to interpret stereoscopic depth. An important theoretical conjecture in this mechanism is that coarse processing precedes and constrains finely detailed processing. We present three types of neurophysiological data from the cat's visual cortex that are consistent with a temporal coarse-to-fine tuning of disparity information. First, the disparity tuning of cortical cells generally sharpened during the time course of response. Second, cells responsive to large and small spatial scale had relatively shorter and longer temporal latencies, respectively. Third, cross-correlation analysis between simultaneously recorded pairs of cortical cells showed that connections between disparity-tuned neurons were generally stronger for coarse-to-fine processing than for fine-to-coarse processing. These results are consistent with theoretical and behavioral studies and suggest that rapid, coarse percepts are refined over time in stereoscopic depth perception.
对于观看三维场景的双眼动物而言，左眼和右眼接收到的信息略有不同，大脑利用这种“双眼视差”来解读立体深度。这一机制中一个重要的理论推测是，粗略处理先于并制约精细处理。我们展示了来自猫视觉皮层的三种神经生理学数据，这些数据与视差信息从时间上的粗略到精细调谐相一致。首先，皮层细胞的视差调谐在反应过程中通常会变得更加敏锐。其次，对大空间尺度和小空间尺度有反应的细胞分别具有相对较短和较长的时间潜伏期。第三，同时记录的成对皮层细胞之间的互相关分析表明，视差调谐神经元之间的连接对于从粗略到精细的处理通常比对从精细到粗略的处理更强。这些结果与理论和行为学研究一致，并表明在立体深度感知中，快速的粗略感知会随着时间的推移而得到细化。
