Saliency affects the width of the audiovisual integration window

Sascha Tyll, Neurology II, University of Magdeburg

Abstract
Previous studies on multimodal integration have shown that an additional stimulus within an unattended modality can improve behavioural performance of the attended one (Bolognini, 2003; Stein, 1996). Here, we investigated whether stimulus saliency modulates the temporal integration window. Visual stimuli (gabor gratings) of different saliency levels were presented with or without sound stimuli, while subjects performed a visual detection task. The stimulus onset asynchrony of visual and auditory stimuli was also manipulated (9 SOAs, range: 200 ms visual leading to 200ms auditory leading, steps: 50ms). Signal detection measures, d-prime and beta, were computed to disentangle perceptual sensitivity from response bias. For less salient stimuli, we found that d-prime was significantly enhanced only for synchronous audiovisual condition (SOA 0 ms) relative to the unimodal visual condition; for more salient stimuli d-prime was significantly enhanced in the range from 50 ms auditory leading to 100 ms visual leading. These results indicate that the integration window widens for the salient target stimuli.

Not available

Back to Abstract