Abstract
Attentional competition between object representations can account for the disappearances of salient targets superimposed upon a moving mask – a phenomenon known as motion-induced blindness (MIB, Bonneh et al., 2001). It has been shown that differences in luminance contrast and in shape between a target and a mask lead to the increase of the disappearances duration in MIB (Bonneh et al., 2001, Hsu et al., 2004). But how many feature differences between the target and the mask components would be sufficient to trigger such competition? We used a target which differed from the mask components either in one or in two features (color and/or motion). Participants reported disappearances in all three experimental conditions, but the amount of disappearances was significantly higher in the condition with two distinguishing features than in the conditions with just one distinguishing feature (either color t(24)=4,282, p≤0,001, or motion t(24)=7,352, p≤0,001). The amount of disappearances was also higher in the condition where the moving target and the mask differed in color as compared to the condition with the static blue target and the moving blue mask (t(24)=4,481, p≤0,001). However, differences in the duration of disappearances reached the level of significance only for the condition with two distinguishing target features and for the “color” condition (t(24)=4,709, p≤0,001). Thus, just one salient feature is enough to trigger competition between object representations. But the more target and mask representations differ in terms of visual features, the more the target disappears.
Supported by Russian Foundation for Basic Research Grant #08-06-00171a.