Ascher D, Grzywacz N M
The Smith-Kettlewell Eye Research Institute, 2318 Fillmore St, 94115, San Francisco, CA, USA.
Vision Res. 2000;40(24):3427-34. doi: 10.1016/s0042-6989(00)00176-0.
Several models have been proposed for how the brain measures velocity from the output of motion-energy units. These models make some unrealistic assumptions such as the use of Gabor-shaped temporal filters, which are non causal, or flat spatial spectra, which are invalidated by existing data. We present a Bayesian model of velocity perception, which makes more realistic assumptions and allows the estimation of local retinal velocity regardless of the specific mathematical form of the spatial and temporal filters used. The model is consistent with several aspects of speed perception, such as the dependence of perceived speed on contrast.
关于大脑如何从运动能量单元的输出中测量速度，已经提出了几种模型。这些模型做出了一些不切实际的假设，比如使用非因果的伽柏形状的时间滤波器，或者平坦的空间频谱，而现有数据证明这些假设是无效的。我们提出了一种速度感知的贝叶斯模型，该模型做出了更现实的假设，并且能够估计局部视网膜速度，而无需考虑所使用的空间和时间滤波器的具体数学形式。该模型与速度感知的几个方面是一致的，比如感知速度对对比度的依赖性。
