Infant information processing across the visual field:from visual perception to social cognition

Detecting information from our rich visual environment is fundamental to guide our attention and to act in the surrounding space. Thus far, infant visual information processing has been primarily studied presenting images within limited visual areas on standard computer displays. This is a simplification of a much richer visual environment in which information derives from a wide space including more peripheral locations. Evidence shows that infants’ peripheral vision is developing during the first postnatal year of life. Nevertheless, most studies used flashing lights and little is known about social and non-social information processing at high eccentricities. The aim of this thesis was to understand how low- and high-level visual information is processed across the developing visual field and how it then translates into social behaviour and more naturalistic environments. This aim was achieved by exploring infants’ sensitivities to different visual information - such as Gabor patches, face-like stimuli and faces expressing emotions - across a wide visual field extending to mid-peripheral locations (up to 60° eccentricity) and by investigating social behaviour during virtual interactions. In Chapter 1, the literature on infant information processing ranging from visual perception to social cognition was presented and the objectives of the thesis were described. In Chapter 2, the extent of the peripheral visual field in response to basic low-level visual stimuli was measured in 9-month-old infants and adults. In Chapter 3, the influence of stimulus content on peripheral information detection was investigated by presenting 9-month-old infants with face-like targets across the visual field. In Chapter 4, a tool for gaze and head tracking beyond standard screen sizes was described. In Chapter 5, attention-getting and attention-holding mechanisms towards different facial emotional expressions appearing at the edge of the developing visual field were investigated in 9-month-olds. In Chapter 6, the gaze following skills of 11- to 12-month-old infants during virtual social interactions were explored. Overall, the results of these studies showed that low- and high-level visual content affects visual field sensitivities and attention. The implications of the results for visual information processing were presented in Chapter 7