Li-Chuan Hsu

A common mechanism for perceptual filling-in and motion-induced blindness ☆

Perceptual-filling-in (PFI) and motion-induced-blindness (MIB) are two phenomena of temporary blindness in which, after prolonged viewing, perceptually salient targets repeatedly disappear and reappear, amidst a field of distracters (i.e., non-targets). Past studies have shown that boundary adaptation is important in PFI, and that depth ordering between target and distracter pattern is important in MIB. Here we show that the reverse is also true; that boundary adaptation is important in MIB, and that depth ordering is important in PFI. Results corroborate our earlier conjecture that PFI and MIB are highly related phenomena that share a common underlying mechanism. We argue that this mechanism involves boundary adaptation, but also that the depth effect shows that boundary adaptation can be no more than a sufficient cause of PFI and MIB, and not a necessary one.

Monocular depth effects on perceptual fading.

After prolonged viewing, a static target among moving non-targets is perceived to repeatedly disappear and reappear. An uncrossed stereoscopic disparity of the target facilitates this Motion-Induced Blindness (MIB). Here we test whether monocular depth cues can affect MIB too, and whether they can also affect perceptual fading in static displays. Experiment 1 reveals an effect of interposition: more MIB when the target appears partially covered by, than when it appears to cover, its surroundings. Experiment 2 shows that the effect is indeed due to interposition and not to the targets contours. Experiment 3 induces depth with the watercolor illusion and replicates Experiment 1. Experiments 4 and 5 replicate Experiments 1 and 3 without the use of motion. Since almost any stimulus contains a monocular depth cue, we conclude that perceived depth affects perceptual fading in almost any stimulus, whether dynamic or static.