We investigated some spontaneous crossmodal correspondances between audition and touch both in blind and sighted people. In four experiments, we tested the interactions between the direction of tactile movement (proximal-distal vs. distal-proximal movement on the fingertip) and change in auditory frequency (increasing vs. decreasing pitch). We measured the compatibility effect between congruent stimuli (proximal-distal tactile movements and increasing pitch, or distal-proximal tactile movement and decreasing pitch) and incongruent stimuli (i.e., the reverse association). The selective attention method, commonly used to test crossmodal correspondences, requires participants to focus on tactile or auditory signals while ignoring the other one presented simultaneously. The results with this method did not reveal any significant compatibility effect. However, a variant of the implicit association task (IAT, e.g., Parise & Spence, 2012) that relies on associations in the response buttons did reveal a significant compatibility effect. This effect was similar in the conditions where the arm was placed vertically and horizontally, that is whether or not the distal-proximal tactile movement corresponded to the free movement of an object subjected to gravity. Finally, in the IAT protocol, similar effects were obtained in blind and in sighted people, i.e., a crossmodal correspondence effect was obtained independently of the arm’s position. These results have methodological implications for the testing of crossmodal correspondences and for the design of sensory substitution devices. They indeed demonstrate the relevance of using spontaneous crossmodal correspondances, and not just arbitrary associations, in order to code aspects of the original signals in conversion systems for blind people.

crossmodal correspondances; audition; touch; implicit association task