Snowden R J, Hess R F
Department of Experimental Psychology, University of Cambridge, England.
Vision Res. 1992 Jan;32(1):61-72. doi: 10.1016/0042-6989(92)90113-w.
The temporal filtering properties of the human peripheral field were investigated by means of measuring: (1) modulation transfer functions for a range of spatial frequencies at four visual field locations (0, 10, 30 and 50 degrees), (2) the contrast of a masking stimulus required to extinguish the visibility of just suprathreshold probes. Results suggest that the number of temporal filters governing detection threshold is dependent upon both eccentricity and spatial frequency. For near-foveal viewing three temporal filters were found (one low-pass and two band-pass), whereas at far eccentricities only one was found (band-pass). A similar result was obtained by modeling the modulation transfer function by simply scaling the sensitivities of three independently derived filters. Our data suggest that (1) changes in the modulation transfer function with respect to spatial frequency and eccentricity can be adequately explained by the changes in sensitivity of a small number of spatio-temporal separable filters; (2) the peripheral field is not merely a coarser version of the fovea but has qualitative differences which may be thought to emphasize the transient properties of the stimulus.
（1）在四个视野位置（0、10、30和50度）测量一系列空间频率下的调制传递函数；（2）测量用于消除刚好高于阈值的探测刺激可见性所需的掩蔽刺激的对比度。结果表明，控制检测阈值的时间滤波器数量取决于离心率和空间频率。对于近中央凹观察，发现了三个时间滤波器（一个低通滤波器和两个带通滤波器），而在远离心率处仅发现一个（带通滤波器）。通过简单地缩放三个独立推导滤波器的灵敏度对调制传递函数进行建模，也得到了类似的结果。我们的数据表明：（1）调制传递函数随空间频率和离心率的变化可以通过少数时空可分离滤波器灵敏度的变化得到充分解释；（2）外周视野不仅仅是中央凹的粗略版本，而是具有质的差异，这可能被认为强调了刺激的瞬态特性。
