Abstract
Purpose: To investigate the visual preferences of human infants and toddlers, using tasks borrowed from adult visual search literature. Method: Infants aged between 2 and 12 months and children between 1 and 4 years, grouped in five age groups (3, 6, 10, 18 and 36 months old; 12 subjects/group) were tested with a preferential looking procedure. The stimuli were presented on cardboard cards containing a target item among 15 distracting items. The task of a naive observer was to make a forced-choice judgement on the side of the card preferred by the subject. Correct guesses yielded a positive score, incorrect guesses a negative one. The tasks investigated were “brightness contrast” (a single dark blob amidst white blobs, or a bright blob amidst dark blobs, on a gray background) and “orientation contrast” (a tilted line amidst vertical lines, or a vertical line amidst tilted lines). Results: Three-year-old children always preferred the discrepant target. Their preference showed an asymmetry consistent with adult visual search asymmetry: they had a higher preference for the darker blob and the tilted line than for the brighter blob and the vertical line. In contrast, three-month-olds showed a positive preference for the darker blob, but no preference for the brighter blob or for lines differing in orientation from their surround. Transition from the infantile to the mature pattern of visual preferences occurred around the end of the first year of age. Conclusion: These results corroborate earlier findings (Sireteanu & Encke, IOVS 1999; 40,4:343, Sireteanu, Wagner & Bachert, IOVS 2001; 42,4:122) and show that the human infant enters the world with a visual repertoire dramatically different from that of adult observers. The sharp transition between infancy and toddlerhood points to the emergence of different brain mechanisms, which mediate a qualitatively different pattern of visual preferences.