title: Does skull shape mediate the relationship between objective features and subjective impressions about the face?
abstract: In our previous work, we described facial features associated with a successful recognition of the sex of the face (Marečková et al., 2011). These features were based on landmarks placed on the surface of faces reconstructed from magnetic resonance (MR) images; their position was therefore influenced by both soft tissue (fat and muscle) and bone structure of the skull. Here, we ask whether bone structure has dissociable influences on observers' identification of the sex of the face. To answer this question, we used a novel method of studying skull morphology using MR images and explored the relationship between skull features, facial features, and sex recognition in a large sample of adolescents (n=876; including 475 adolescents from our original report). To determine whether skull features mediate the relationship between facial features and identification accuracy, we performed mediation analysis using bootstrapping. In males, skull features mediated fully the relationship between facial features and sex judgments. In females, the skull mediated this relationship only after adjusting facial features for the amount of body fat (estimated with bioimpedance). While body fat had a very slight positive influence on correct sex judgments about male faces, there was a robust negative influence of body fat on the correct sex judgments about female faces. Overall, these results suggest that craniofacial bone structure is essential for correct sex judgments about a male face. In females, body fat influences negatively the accuracy of sex judgments, and craniofacial bone structure alone cannot explain the relationship between facial features and identification of a face as female.
authors: Rotman Research Institute, University of Toronto, 3560 Bathurst Street, Toronto, Ontario M6A 2E1, Canada. klara.mareckova@gmail.com
authors: Klára
authors: K
authors: Marečková
authors: M Mallar
authors: MM
authors: Chakravarty
authors: Mei
authors: M
authors: Huang
authors: Claire
authors: C
authors: Lawrence
authors: Gabriel
authors: G
authors: Leonard
authors: Michel
authors: M
authors: Perron
authors: Bruce G
authors: BG
authors: Pike
authors: Louis
authors: L
authors: Richer
authors: Suzanne
authors: S
authors: Veillette
authors: Zdenka
authors: Z
authors: Pausova
authors: Tomáš
authors: T
authors: Paus
mesh_terms: D000273:Adipose Tissue / Q000503:physiopathology*; D000293:Adolescent; D002508:Cephalometry / Q000379:methods; D002648:Child; D003463:Cues; D003657:Decision Making / Q000502:physiology; D005145:Face / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D054881:Sex Determination by Skeleton / Q000379:methods*; D012737:Sex Factors; D012886:Skull / Q000033:anatomy & histology*; D014796:Visual Perception / Q000502:physiology*