Abstract
[Purpose] After the exposure to overlapped sinusoidal gratings with different spatial frequencies moving in the opposite directions, motion aftereffect of the high spatial frequency grating was seen with a static test while that of the low spatial frequency was seen with a flicker test and we interpreted the results by assuming the slow and fast motion detectors (VSS '06). There was no difference in flicker MAE between the global and local motion while longer MAE was found for global motion in static MAE, suggesting selective contribution of the slow motion detector to global motion (VSS '07). The purpose of the study is to investigate how the slow and fast motion detectors differ in contribution to global motion perception.
[[gt]][Experiment] We measured MAE duration of rotation or expansion/contraction using four gabor patches arranged circularly (above, right, below and left of the fixation). Each patch had two sinusoidal components with different spatial frequencies (0.53 and 2.13 c/deg), which moved in the opposite directions at 5 Hz. In one condition, the four patches presented simultaneously while top and bottom pair and left and right pair were presented alternately every one second in the other condition. A blank field was presented every one second to equate the duration of local adaptation in the four-patch conditions to that in two-patch alteration. After 10, 20 or 40s of adaptation, MAE duration was measured in the static or the flicker (4 Hz) version of the four gabor patches.
[Results] The static MAE showed longer duration after the four-patch adaptation than after two-patch adaptation. In contrast, the flicker MAE showed similar duration in all adaptation conditions. The results indicate that the output from the slow motion detector is integrated for seeing global motion.
MESSC GASR(B) 18330153-2007