Crossmodal Correspondences: Standing Issues and Experimental Guidelines.

Crossmodal correspondences refer to the systematic associations often found across seemingly unrelated sensory features from different sensory modalities. Such phenomena constitute a universal trait of multisensory perception even in non-human species, and seem to result, at least in part, from the adaptation of sensory systems to natural scene statistics. Despite recent developments in the study of crossmodal correspondences, there are still a number of standing questions about their definition, their origins, their plasticity, and their underlying computational mechanisms. In this paper, I will review such questions in the light of current research on sensory cue integration, where crossmodal correspondences can be conceptualized in terms of natural mappings across different sensory cues that are present in the environment and learnt by the sensory systems. Finally, I will provide some practical guidelines for the design of experiments that might shed new light on crossmodal correspondences.