Early Interplay of Smell and Sight in Human Development: Insights for Early Intervention With High-Risk Infants

Purpose of Review: In this narrative review, the early interplay between olfaction and vision is analysed, highlighting clinical effects of its manipulation in typical subjects and in presence of visual disorders. In addition, new methods of early intervention, based on this multisensory interaction, and their applications on different infant populations at risk of neurodevelopmental disabilities are discussed. Recent Findings: Multisensory processes permit combinations of several inputs, coming from different sensory systems, playing a key role in human neurodevelopment, and permitting an adequate and efficient interaction with the environment. In particular, during the early stages of life, the olfactory and the visual systems appear to interact to facilitate the adaptation and the mutual bond with the caregiver and to mediate the development of social attention of the infant, although, at birth, the olfactory system is much more mature than the visual system. Summary: Although the results from this line of research are promising, mechanisms at the basis of this interlink between sight and smell are unclear, so more work needs to be done before concluding that a multisensory approach, based on visual and olfactory stimulations, is applicable in clinical practice.