title: The hollow-face illusion in infancy: do infants see a screen based rotating hollow mask as hollow?
abstract: We investigated whether infants experience the hollow-face illusion using a screen-based presentation of a rotating hollow mask. In experiment 1 we examined preferential looking between rotating convex and concave faces. Adults looked more at the concave-illusory convex-face which appears to counter rotate. Infants of 7- to 8-month-old infants preferred the convex face, and 5- to 6-month-olds showed no preference. While older infants discriminate, their preference differed from that of adults possibly because they don't experience the illusion or counter rotation. In experiment 2 we tested preference in 7- to 8-month-olds for angled convex and concave static faces both before and after habituation to the stimuli shown in experiment 1. The infants showed a novelty preference for the static shape opposite to the habituation stimulus, together with a general preference for the static convex face. This shows that they discriminate between convex and concave faces and that habituation to either transfers across a change in view. Seven- to eight-month-olds have been shown to discriminate direction of rigid rotation on the basis of perspective changes. Our results suggest that this, perhaps together with a weaker bias to perceive faces as convex, allows these infants to see the screen-based hollow face as hollow even though adults perceive it as convex.
authors.affiliation: Research and Development Initiative, Chuo University, 742-1 Higashinakano, Hachioji, Tokyo, 192-0393, Japan; e-mail:  aki.tsuruhara@gmail.com.
authors.forename: Aki
authors.initials: A
authors.lastname: Tsuruhara
authors.forename: Emi
authors.initials: E
authors.lastname: Nakato
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Otsuka
authors.forename: So
authors.initials: S
authors.lastname: Kanazawa
authors.forename: Masami K
authors.initials: MK
authors.lastname: Yamaguchi
authors.forename: Harold
authors.initials: H
authors.lastname: Hill
keywords: Hollow-face illusion; convexity preference; depth perception; face perception; infants