Preverbal Infants’ Sensitivity to Synaesthetic Cross-Modality Correspondences

TLDR

Cross‑modal correspondences, such as higher‑pitched sounds producing brighter, higher, and sharper visual images, are thought to reflect innate synaesthetic links, yet the youngest children with confirmed evidence are 2‑ to 3‑year‑olds. The study aimed to determine whether 3‑ to 4‑month‑old infants are sensitive to pitch‑height and pitch‑sharpness correspondences. The authors employed a preferential‑looking paradigm to assess this sensitivity. Infants looked longer at congruent audiovisual changes than incongruent ones, providing the strongest evidence to date that such cross‑modal correspondences are innate.

Abstract

Stimulation of one sensory modality can induce perceptual experiences in another modality that reflect synaesthetic correspondences among different dimensions of sensory experience. In visual-hearing synaesthesia, for example, higher pitched sounds induce visual images that are brighter, smaller, higher in space, and sharper than those induced by lower pitched sounds. Claims that neonatal perception is synaesthetic imply that such correspondences are an unlearned aspect of perception. To date, the youngest children in whom such correspondences have been confirmed with any certainty were 2- to 3-year-olds. We examined preferential looking to assess 3- to 4-month-old preverbal infants’ sensitivity to the correspondences linking auditory pitch to visuospatial height and visual sharpness. The infants looked longer at a changing visual display when this was accompanied by a sound whose changing pitch was congruent, rather than incongruent, with these correspondences. This is the strongest indication to date that synaesthetic cross-modality correspondences are an unlearned aspect of perception.