Neonatal Synesthesia: Implications for the Processing of Speech And Faces

A re-analysis of the published literature and new data of my own support the hypothesis that babies confuse the input from different senses. That synesthetic mixing leads to (1) apparent cross-modal matching, which becomes more difficult to demonstrate with increasing age; (2) responses from primary cortical areas to input from the “wrong” senses; (3) shifting visual preferences; and (4) the summation of sensory inputs in determining the baby’s sleep. The hypothesis of neonatal synesthesia has major implications for studies of young infants and may explain some of the inconsistencies in the literature.