title: Natural, but not artificial, facial movements elicit the left visual field bias in infant face scanning.
abstract: A left visual field (LVF) bias has been consistently reported in eye movement patterns when adults look at face stimuli, which reflects hemispheric lateralization of face processing and eye movements. However, the emergence of the LVF attentional bias in infancy is less clear. The present study investigated the emergence and development of the LVF attentional bias in infants from 3 to 9 months of age with moving face stimuli. We specifically examined the naturalness of facial movements in infants'LVF attentional bias by comparing eye movement patterns in naturally and artificially moving faces. Results showed that 3- to 5-month-olds exhibited the LVF attentional bias only in the lower half of naturally moving faces, but not in artificially moving faces. Six- to 9-month-olds showed the LVF attentional bias in both the lower and upper face halves only in naturally moving, but not in artificially moving faces. These results suggest that the LVF attentional bias for face processing may emerge around 3 months of age and is driven by natural facial movements. The LVF attentional bias reflects the role of natural face experience in real life situations that may drive the development of hemispheric lateralization of face processing in infancy.
authors: University of Toronto, 45 Walmer Road, Toronto, Ontario, Canada M5R 2X2. Electronic address: naiqi.xiao@mail.utoronto.ca.
authors: Naiqi G
authors: NG
authors: Xiao
authors: University of Delaware, Newark, DE 19716, United States. Electronic address: pquinn@psych.udel.edu.
authors: Paul C
authors: PC
authors: Quinn
authors: University of Toronto, 45 Walmer Road, Toronto, Ontario, Canada M5R 2X2. Electronic address: andrea.wheeler@utoronto.ca.
authors: Andrea
authors: A
authors: Wheeler
authors: LPNC - Université Grenoble Alpes, CNRS, Grenoble 38400, France. Electronic address: olivier.pascalis@upmf-grenoble.fr.
authors: Olivier
authors: O
authors: Pascalis
authors: University of Toronto, 45 Walmer Road, Toronto, Ontario, Canada M5R 2X2. Electronic address: kang.lee@utoronto.ca.
authors: Kang
authors: K
authors: Lee
mesh_terms: D015982:Bias; D005133:Eye Movements; D005145:Face; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007223:Infant; D008297:Male; D009068:Movement / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D014794:Visual Fields / Q000502:physiology*
keywords: Developmental change; Eye movements; Face processing; Infants; Left visual field bias; Natural facial movements