RESUMO
BACKGROUND: The frequency components of the human voice play a major role in signalling the gender of the speaker. A voice imitation study was conducted to investigate individuals' ability to make behavioural adjustments to fundamental frequency (F0), and formants (Fi) in order to manipulate their expression of voice gender. METHODOLOGY/PRINCIPAL FINDINGS: Thirty-two native British-English adult speakers were asked to read out loud different types of text (words, sentence, passage) using their normal voice and then while sounding as 'masculine' and 'feminine' as possible. Overall, the results show that both men and women raised their F0 and Fi when feminising their voice, and lowered their F0 and Fi when masculinising their voice. CONCLUSIONS/SIGNIFICANCE: These observations suggest that adult speakers are capable of spontaneous glottal and vocal tract length adjustments to express masculinity and femininity in their voice. These results point to a "gender code", where speakers make a conventionalized use of the existing sex dimorphism to vary the expression of their gender and gender-related attributes.