Figure 1.

(A) Examples of basic neutral faces (male and female) and their modified versions. The changes in features are depicted in the two upper rows. On the left enlarged eye size; on the right enlarged mouth size. The changes in non-emotional expressions are depicted in the middle rows. On the left the change occurred in the upper part of the face; on the right the change occurred in the lower part of the face. The changes in emotional expression version are depicted in the lower rows. On the left a happy expression; on the right a sad expression. (B) Stimuli are showed inverted. Each manipulation complied with the parameters of biological compatibility.