The importance of social touch for infant social-emotional development: integrating neuroimaging, psychophysiological, endocrine, and behavioral evidence

Abstract

Touch is essential to the establishment of affective bonds and to our well-being. The interpersonal touch experience is particularly important in early childhood since it is the most fundamental form of parental care. However, the study of this sensory modality remains surprisingly neglected. More specifically, little is known about the perception and processing of social touch, as well as its impact on adaptive stress responses in infants. This FAPESP Young Researcher (Phase 2) proposal is organized in four studies that focus on complementing research questions and methods which, taken together, aim to make substantial contributions to scientific knowledge on social touch in infancy. Study 1 aims to clarify the patterns of neural activation in response to social touch in infants, while Study 2 will analyze the impact of partner identity (mother versus unfamiliar female) on the neural and cardiac responses to social touch in the first year of life. In turn, Study 3 aims to illuminate the potential mediating role of these cardiac and neural activation patterns in the relationship between maternal touching behaviors and infant behavioral and endocrine stress responses. Finally, Study 4 will be devoted to the development of a novel fNIRS hyperscanning protocol for application in infant-caregiver interactions which will in turn enable the assessment of the partners' neural and cardiac synchrony during a touch interaction. The studies that compose this proposal aim to significantly expand scientific knowledge on the characterization and importance of social touch in infancy, integrating functional neuroimaging, psychophysiology, endocrinology, and behavioral evidence at a critical age for social-emotional development. (AU)