Sheliga B M, Fitzgibbon E J, Miles F A
Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, MD, USA.
J Vis. 2009 Nov 9;9(12):2.1-38. doi: 10.1167/9.12.2.
We recorded the initial torsional Ocular Following Responses (tOFRs) elicited at short latency by visual images that occupied the frontal plane and rotated about the lines of sight. Using 1-D radial gratings, the local spatio-temporal characteristics of these tOFRs closely resembled those we previously reported for the hOFRs to horizontal motion with 1-D vertical gratings. When the 1-D radial grating was subdivided into a number of concentric annuli, each with the same radial thickness, tOFRs were less than predicted from the sum of the responses to the individual annuli: spatial normalization. However, the normalization was much weaker than that which we previously reported for the hOFRs. Further, when the number, thickness and contrast of these concentric annuli were varied systematically, the latency and magnitude of the tOFRs were well described by single monotonic functions when plotted against the product of the total area of the annuli and the square of their Michelson contrast ("AC(2)"), consistent with the hypothesis that the onset and magnitude of the initial tOFR are determined by the total motion energy in the stimulus. When our previously published hOFR data were plotted against AC(2), a single monotonic function sufficed to describe the latency but not the magnitude.
我们记录了由占据额平面并绕视线旋转的视觉图像在短潜伏期引发的初始扭转性眼跟踪反应（tOFRs）。使用一维径向光栅，这些tOFRs的局部时空特征与我们之前报道的用一维垂直光栅对水平运动的hOFRs的特征非常相似。当将一维径向光栅细分为多个具有相同径向厚度的同心环带时，tOFRs小于根据对各个环带的反应之和所预测的值：空间归一化。然而，这种归一化比我们之前报道的hOFRs的归一化要弱得多。此外，当系统地改变这些同心环带的数量、厚度和对比度时，将tOFRs的潜伏期和幅度相对于环带总面积与其迈克尔逊对比度的平方的乘积（“AC(2)”）作图时，它们可以很好地用单一单调函数来描述，这与初始tOFR的起始和幅度由刺激中的总运动能量决定的假设一致。当将我们之前发表的hOFR数据相对于AC(2)作图时，一个单一单调函数足以描述潜伏期，但不能描述幅度。
