Fluidity of gender identity induced by illusory body-sex change.

Gender identity is a collection of thoughts and feelings about one's own gender, which may or may not correspond to the sex assigned at birth. How this sense is linked to the perception of one's own masculine or feminine body remains unclear. Here, in a series of three behavioral experiments conducted on a large group of control volunteers (N = 140), we show that a perceptual illusion of having the opposite-sex body is associated with a shift toward a more balanced identification with both genders and less gender-stereotypical beliefs about own personality characteristics, as indicated by subjective reports and implicit behavioral measures. These findings demonstrate that the ongoing perception of one's own body affects the sense of one's own gender in a dynamic, robust, and automatic manner.