A new study demonstrates that the majority of women who claim they’re heterosexual are aroused by videos of naked men and naked women. Led by Doctor Gerulf Rieger from the Department of Psychology at the University of Essex, the study showed several videos of naked men and women to 235 women and gauged their responses. Their findings? 82% of the women tested wound up aroused by both sexes. This was confirmed by whether or not their pupils dilated in response to sexual stimuli.

Of the women who claimed to be straight, 74% wound up being extremely aroused by footage of attractive men and attractive women. On the other hand, lesbians demonstrate much stronger sexual responses to women than to men. According to Dr. Riegler, the study showed lesbians who may dress “in a more masculine manner” don’t necessarily have more “masculine behaviors,” stating:

“Even though the majority of women identify as straight, our research clearly demonstrates that when it comes to what turns them on, they are either bisexual or gay, but never straight. Although some lesbians were more masculine in their sexual arousal, and others were more masculine in their behaviors, there was no indication that these were the same women. This shows us that how women appear in public does not mean that we know anything about their sexual role preferences.”