Summation of visual attributes in auditory-visual crossmodal correspondences

Crossmodal correspondences are a feature of human perception in which two or more sensory dimensions are linked together; for example, high-pitched noises may be more readily linked with small than with large objects. However, no study has yet systematically examined the interaction between different visual-auditory crossmodal correspondences. We investigated how the visual dimensions of luminance, saturation, size, and vertical position can influence decisions when matching particular visual stimuli with high-pitched or low-pitched auditory stimuli. For multidimensional stimuli, we found a general pattern of summation of the individual crossmodal correspondences, with some exceptions that may be explained by Garner interference. These findings have applications for the design of sensory substitution systems, which convert information from one sensory modality to another.