Abstract
Some similarities between sex differences and sexual orientation differences, with gay men shifted in female-typical directions and lesbians shifted in male-typical directions, have been hypothesized to reflect the effects of prenatal androgen exposure. This report assessed sex-linked personality and cognitive traits in a Spanish sample of 1117 straight (i.e., heterosexual) and non-straight (i.e., non-heterosexual) men and women, using finger-length ratio (2D:4D) as an index of prenatal androgen exposure. Observed sex differences were in the expected direction: Measures of right-hand 2D:4D, left-hand 2D:4D, and anxiety were higher in straight women than men, whereas impulsivity, dominance, cognitive reflection, and mathematical proficiency were higher in straight men than women. Gay men proved to be shifted in a female-typical direction compared to straight men for right-hand 2D:4D, left-hand 2D:4D, anxiety, and cognitive reflection; they were intermediate for dominance and mathematics, and were shifted in a male-typical direction for impulsivity. Lesbians were shifted in a male-typical direction compared to straight women for left-hand 2D:4D, anxiety, cognitive reflection, and mathematics; and they were shifted in a highly female-typical direction for impulsivity and dominance (scoring lower than straight women). Observed sex-linked shifts in gay men and lesbians were larger for psychological traits that displayed larger sex differences, and smallest for impulsivity (which displayed the smallest sex difference). Evidence also suggested that sex-related measures were linked to 2D:4D in theoretically meaningful ways. In conclusion, this report suggests a plausible role of androgens as prenatal determinants of sex-linked personality and cognitive traits in straight and non-straight men and women.
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Acknowledgements
I wish to thank the editor and reviewers for many helpful suggestions. I also thank the all participants for their cooperation and José Aguilar Doblas for constructing the methacrylate box used to take the photographs of the participants' hands. I am particularly grateful to Carlos J. Nogales for his valuable help in data collection.
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Aguilar, R. Finger-Length Ratios and Sexual Orientation in Southern Spain: A Large Sample Study on Sex-Linked Personality and Cognitive Traits. Arch Sex Behav 52, 3301–3312 (2023). https://doi.org/10.1007/s10508-023-02670-y
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DOI: https://doi.org/10.1007/s10508-023-02670-y