Researchers at Northwestern University have found bisexual physiological arousal patterns in men, effectively disproving that men are either “straight, gay or lying.” This result is particularly significant because a similar study in 2005 by the same lab did not find unique arousal patterns in bisexual men.
Arousal was measured two ways: First, by how excited the men were by the pictures and by changes in erections. About a third of the men had low erection response and were excluded from the results. In contrast to the bisexual men in the earlier study, their erection responses were indeed bisexual in nature.
The principal differences between the current and earlier study were in recruitment and inclusion criteria. Where the earlier study recruited bi men from gay and alternative publications, the current study recruited from online forums especially likely to reach bisexual men. In addition, the researchers specified that bi men must have had sex with at least two women and two men, and been in a three-month relationship with someone of each sex.
Separate studies of female arousal have found that many if not most women exhibit a bisexual physiological arousal pattern, though they vary in how consciously aware they are of this response. While some researchers contend that arousal patterns underlie sexual orientation, bi activists have argued that orientation is complex mix of factors. In any case, as reported by the New York Times and elsewhere, the new findings validate the identities of bisexual men.
The American Institute of Bisexuality, founded by the late Fritz Klein M.D., funded the research and assisted with recruiting after reaching out to the principal investigator, Professor J. Michael Bailey. The results are part of a larger set of studies underway that include fMRI scans to study brain arousal responses of straight, gay and bisexual men and women.