Abstract
Past studies have shown that incongruent visual information can bias the perception of location of sound, as well as the perception of sound identification. We used an audiovisual Stroop-like task to investigate whether incongruent sound and shape information interferes with stimulus identification at a conceptual level. Healthy undergraduates learned to identify novel shapes that were associated with distinct sounds and non-words (e.g., a curved shape has a high-pitched sound and is called “baiv”). After an initial training phase, participants completed a speeded naming task where they were simultaneously presented with a shape and a sound. They were instructed to identify the shape, the sound, or the stimulus presented, and the order of conditions was counterbalanced across participants. Crucially, 25% of test trials consisted of incongruent information: the sound and shape presented were not one of the learned associations. An analysis of the reaction times revealed a main effect of instructions: participants responded fastest when identifying shapes, and slowest when identifying sounds. We also observed a main effect of congruency: participants responded faster on congruent trials than on incongruent trials. These main effects were qualified by a two-way interaction between instructions and congruency: the size of the interference was largest when participants were asked to identify the sound and ignore visual information. This study demonstrates that incongruent information can impact the identification of stimuli at a conceptual level. Importantly, though vision is perceived as being the dominant sense in humans, irrelevant sound information still interfered with visual shape identification.
Mount Allison University.