The question whether some men have a bisexual orientation—that is, whether they are substantially sexually aroused and attracted to both sexes—has remained controversial among both scientists and laypersons. Skeptics believe that male sexual orientation can only be homosexual or heterosexual, and that bisexual identification reflects nonsexual concerns, such as a desire to deemphasize homosexuality. Although most bisexual-identified men report that they are attracted to both men and women, self-report data cannot refute these claims. Patterns of physiological (genital) arousal to male and female erotic stimuli can provide compelling evidence for male sexual orientation. (In contrast, most women provide similar physiological responses to male and female stimuli.) We investigated whether men who self-report bisexual feelings tend to produce bisexual arousal patterns. Prior studies of this issue have been small, used potentially invalid statistical tests, and produced inconsistent findings. We combined nearly all previously published data (from eight previous studies in the United States, United Kingdom, and Canada), yielding a sample of 474 to 588 men (depending on analysis). All participants were cisgender males. Highly robust results showed that bisexual-identified men’s genital and subjective arousal patterns were more bisexual than were those who identified as exclusively heterosexual or homosexual. These findings support the view that male sexual orientation contains a range, from heterosexuality, to bisexuality, to homosexuality.

一些男性是否有双性取向——即他们是否对两性都有强烈的性唤起和吸引力——这个问题在科学家和外行人中仍然存在争议。怀疑论者认为，男性性取向只能是同性恋或异性恋，而双性恋认同反映了非性的担忧，例如淡化同性恋的愿望。尽管大多数双性恋男性报告说他们对男性和女性都有吸引力，但自我报告数据无法反驳这些说法。男性和女性色情刺激的生理（生殖器）唤醒模式可以为男性性取向提供令人信服的证据。 （相比之下，大多数女性对男性和女性刺激产生相似的生理反应。）我们调查了自我报告双性恋感受的男性是否倾向于产生双性唤起模式。先前对此问题的研究规模较小，使用了可能无效的统计测试，并得出了不一致的结果。我们结合了几乎所有先前发表的数据（来自美国、英国和加拿大之前的八项研究），产生了 474 至 588 名男性样本（取决于分析）。所有参与者均为顺性别男性。高度稳健的结果表明，被认定为双性恋的男性的生殖器和主观性唤起模式比那些被认定为完全异性恋或同性恋的男性更具有双性恋特征。这些发现支持这样的观点，即男性性取向包含从异性恋、双性恋到同性恋的一系列范围。