Purchase this article with an account.
Sandra Arranz-Paraiso, Ignacio Serrano-Pedraza; The effect of relative size on the interactions between motion sensors tuned to fine and coarse scale. Journal of Vision 2018;18(10):337. doi: 10.1167/18.10.337.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Motion discrimination of high spatial-frequency stimuli is impaired when a static low spatial-frequency component is added to it. However, motion discrimination is facilitated when a static high-frequency component is added to a low-frequency moving stimulus (Serrano-Pedraza et al., 2013 JoV). Previous studies show that this interaction between motion sensors tuned to fine and coarse scales depends on the relative contrast and size of both coarse and fine scale stimuli (Serrano-Pedraza & Derrington, 2010, JoV). In this experiment, we extend these studies by testing the effect of the relative size of the high- and low-frequency components in order to measure the contribution of each motion sensor to the mechanism responsible for this interaction. Using Bayesian staircases, we measured duration thresholds for 7 subjects in a motion discrimination task. We used vertical Gabor patches of frequencies 1 and 3c/deg and 28% contrast. Four conditions were tested, 1 c/deg moving, 3c/deg moving, 1 static added to a 3 c/deg moving (1s+3m), and 1c/deg moving added to a 3c/deg static (1m+3s). For each condition, five different diameters (2Sxy) were used (0.5, 1, 2, 3, & 4deg), therefore testing in total 30 combinations of different sizes. Our results show that duration thresholds for the condition 1s+3m increase with increasing size, and the strongest suppressive interaction is reached when the size of both components is maximum. However, for the condition 1m+3s, we found the opposite behavior: duration thresholds decrease with increasing size. For the biggest sizes, we found a facilitation effect: duration thresholds were lower than the thresholds for detecting the condition 1m with the same size. The analysis of the results from relative sizes, suggest that the size of the high spatial-frequency component is the relevant dimension for the activation of the motion mechanism underlying this interaction between motion sensors tuned to different scales.
Meeting abstract presented at VSS 2018
This PDF is available to Subscribers Only