Sex Categorization of Face Stimuli

We used VAS to assess the extent to which each of the presented face stimuli was perceived as male or female. In each trial, a VAS with the left extrema labeled male and the right extrema labeled female, was displayed underneath each centrally presented face image and participants were asked to indicate the degree of perceived male- or femaleness by moving an initially centrally located slider with the cursor. For analyses, the response of the participants on the sliding scale was translated into a rating ranging from 0 (male) to 100 (female). Two cut-off values were set a priori: ratings from 0 to 20 corresponding to “unambiguously male” and ratings from 80 to 100 corresponding to “unambiguously female.” A rating of 50 was defined as “sex-ambiguous.” We decided to set the cut-offs more extreme compared to the ones set in a previous study (unambiguous maleness and femaleness at values 28.57 and 71.43, respectively; Armann and Bülthoff, 2012) in order to allow for a greater differentiation of the ratings.