The relationship between temperament and sexual orientation

BackgroundThe relationship between temperament and sexual orientation has been poorly characterized. We have used the Affective and Emotional Composite Temperament (AFECT) model to evaluate this association in a large population sample.MethodsData from 16,571 subjects between 21 and 45 years old (mean age=29.1±6.3 yrs, 69.4% females) was collected anonymously through Internet in Brazil.ResultsRegarding affective temperaments, male cyclothymics and dysphorics had the lowest percentage of people with heterosexual orientation and the highest percentages of people with bisexual and homosexual orientations. The opposite profile was observed in hyperthymic and euthymic types. Among females, the volatile, cyclothymic, apathetic, disinhibited and euphoric types were less often observed in people with “pure” heterosexual orientation and more often in people with bisexual orientation. In men only, homosexuality was more common among the depressive, cyclothymic and dyphorics temperaments. Emotional trait analysis showed that heterosexual subjects differed statistically from all other groups by having higher scores of coping and stability and lower scores of sensitivity and desire. Overall, the effect sizes were small to moderate, with the largest differences between “pure” heterosexuals and people with bisexual orientation, particularly in women. Subjects with heterosexual orientation who have had homosexual experience and those with homosexual orientation presented intermediate scores.LimitationsCross-sectional design, lack of potentially important covariates (e.g., maltreatment) and data collected by Internet only.ConclusionExternalized and unstable traits were associated mainly with bisexuality. The group of heterosexuals with homosexual fantasies or experiences offers a new approach for the study of sexual orientation.