Alexandra Kurenkova

Background. Despite the abundance of human face recognition models and research carried out in this area over the past half-century, there are still open questions about the uniqueness of the facial perception processes and about the oneness or difference of the mechanisms of perception of familiar and unfamiliar faces.

Objective. Research into the mechanisms of perception of (a)symmetry of familiar and unfamiliar faces.

Study Participants. 34 people participated in the study: 25 classmates (11 female and 14 male, Мage = 16, SD = 0,49) and 9 teachers (6 female and 3 male, Мage = 33, SD = 8,71).

Methods. Methods of inversion and horizontal mirroring of face images were used to compare the mechanisms of perception of facial symmetry in familiar and unfamiliar faces. Mirroring allowed to change the face itself without violating its recognition and maintaining the overall degree of its (a)symmetry. The inversion impaired the perception of the facial configuration. Study participants assessed the degree of asymmetry in the images of familiar (photographs of classmates) and unfamiliar faces in four presentation conditions: original / mirrored faces presented upright / inverted.

Results. The study results demonstrated that when presented upright, familiar mirrored faces are perceived as more asymmetrical than the original ones; no difference was revealed for unfamiliar faces. When inverting images, the ratings of the original and mirrored versions of the faces do not differ significantly for both familiar and unfamiliar faces. A small inversion effect was found in the ratings of original familiar faces: inverted familiar faces were rated as more asymmetrical than upright ones.

Conclusions. The study results generally support the hypothesis that the mechanisms of perception of (a)symmetry in familiar and unfamiliar faces differ. Furthermore, there is reason to consider the assessment of a face (a)symmetry as involving not only configural, but also analytical mechanisms of its perception.