Narasimhan Sathyasri, Giaschi Deborah
University of British Columbia, Department of Ophthalmology and Visual Sciences, Vancouver, BC, Canada.
Vision Res. 2012 Jun 1;62:102-7. doi: 10.1016/j.visres.2012.02.016. Epub 2012 Apr 11.
The purpose of this study was to investigate the effect of dot speed and dot density on the development of global motion perception by comparing the performance of adults and children (5-6years old) on a direction-discrimination task. Motion coherence thresholds were measured at two dot speeds (1 and 4deg/s) and three dot densities (1, 15, 30dots/deg(2)). Adult coherence thresholds were constant at approximately 9%, regardless of speed or density. Child coherence thresholds were significantly higher across conditions, and were most immature at the slow speed and at the sparse density. Thus, the development of global motion perception depends heavily on stimulus parameters. This finding can account for some of the discrepancy in the current developmental literature. Our results, however, caution against making general claims about motion deficits in clinical populations based on only a single measurement at a specific combination of speed and density.
本研究的目的是通过比较成年人和儿童（5 - 6岁）在方向辨别任务中的表现，来探究点速度和点密度对整体运动感知发展的影响。在两种点速度（1和4度/秒）和三种点密度（1、15、30点/度²）下测量运动连贯性阈值。无论速度或密度如何，成年人的连贯性阈值都恒定在约9%。儿童的连贯性阈值在各种条件下都显著更高，并且在低速和稀疏密度下最不成熟。因此，整体运动感知的发展在很大程度上取决于刺激参数。这一发现可以解释当前发育文献中的一些差异。然而，我们的结果提醒不要仅基于在特定速度和密度组合下的单次测量就对临床人群的运动缺陷做出一般性断言。
