ERP evidence that surface-based attention biases interocular competition during rivalry

Abstract

J. F. Mitchell, G. R. Stoner, and J. H. Reynolds (2004) observed that exogenously cuing one of two superimposed transparent surfaces resulted in an enhanced perceptual bias for the cued surface during binocular rivalry. We investigated the neural bases of this effect by recording event-related potentials (ERPs). Subjects viewed two superimposed rotating transparent surfaces and compared the directions of two successive translations, either both of the same surface or one of each surface. Following the first translation, which cued attention to the translating surface, two surface images were removed-one from each eye (dichoptic viewing) or both from one eye (monocular viewing). Subjects were impaired at comparing the first and second translations when they occurred on different surfaces, and the impairment was greater during dichoptic viewing (rivalry). The P1 component (110-160 ms) of the ERP elicited by the second translation of the same surface was larger than for the different surface during dichoptic but not monocular viewing. Larger cueing effects were also observed for the subsequent posterior N1 (160-220 ms) and P2 (250-300 ms) components during rivalry than during monocular viewing. These results are in line with a hybrid model of rivalry whereby cuing one surface initiates an earlier interocular selection process when the competing surfaces are presented to separate eyes.