Abstract
Purpose: On the Motion-Induced Blindness (MIB), the target dots are invisible spontaneously or stochastically. We investigate, however, the mask or noise patterns that induce synchronous disappearance of the targets. With the new inducing masks we could find MIB where a fairly large target figure, rather than conventional dots, would slips away from our consciousness. A ring target of 5 degree size is tried.
Methods: Experiment1: At 5 degree eccentric position, the 3 white dots, 0.25 degree of size forming a triangle were displayed statically on the black background with the central fixation point. Surrounding the each target, one or two concentric blue rings were displayed. In the motion condition, the rings were expanding and shrinking at 2 degree/s velocity between 0.1 degree and 2 degree from the outer edge of the target. In the ON-OFF condition, one inducing ring simply turned on and off at 1 degree apart from the target at 1Hz which was far slower than conventional Flicker-Induced Blindness (FIB). Experiment2: the target was a white ring of 5 degree size whose thickness could vary from fairy thin to thick. The inducing mask is also the concentric blue rings which were at either inside of the target or outside or both. The motion condition and ON-OFF condition are the same as the Experiment1.
Results: Experiment1: In the motion condition, while inducing rings were expanding, the onset moment of the most inner ring, the 3 target dots were disappeared synchronously and they are visible again when the mask rings started shrinking. In the ON-OFF condition we observe less effective disappearances. Experiment2: The observers saw occasionally totally invisible ring.
Discussion: Relatively few accounts were published on the moment of disappearance. This is simply because the masks were generally random or at least independent of the target.