Bisexuality might not exist, a Northwestern graduate student determined through psychological study.

That statement generated nationwide attention and raised some students’ fears of increased discrimination against lesbian, gay, bisexual and transgender students.

The study, published last month in the journal Psychological Science, included 101 men. Psychology doctoral student Gerulf Rieger, who led the study under the supervision of psychology Prof. J. Michael Bailey, said the results corroborate the theory that men are either gay or straight – not bisexual.

“There has always been skepticism about whether bisexual arousal truly exists,” Rieger said.

Regardless of whether the men considered themselves gay, straight or bisexual, they showed about four times more arousal to one sex than the other.

Thirty of the men in the study described themselves as heterosexual, 33 as bisexual and 38 as homosexual. Subjects then rated their sexual orientation between zero and six, with a score in the middle of the scale indicating bisexuality.

As subjects viewed movies of naked men and naked women, sensors monitored the subjects’ genital arousal. The men also subjectively gauged their own responses.

Kelsey Pacha, outreach and education chairwoman for the LGBT advocacy student group Rainbow Alliance, said the results could create more conflict about sexual orientation issues.

“I don’t think that (the view that bisexuality doesn’t exist) is going to be very helpful for any community, whether gay or straight,” said Pacha, a Weinberg sophomore. “It’s saying that there’s no leeway, that you’re either 100 percent gay or 100 percent straight.”

The bisexuality study was highly publicized, and an article about it in The New York Times became one of the newspaper’s most widely e-mailed stories this summer.

Critics have said the sample size was too small to draw definitive conclusions, but Rieger disagreed.

“If you repeated the experiment with only gay or straight men, I don’t think anyone would doubt the accuracy of (the subjects’) reactions,” he said.

Bailey said Rieger’s study was scientifically sound but further research is needed on the subject.

“There’s a lot of skepticism about the existence of truly bisexual men, and our study, I think, supports that skepticism,” Bailey said. “I have no agenda to question bisexual people. It’s just what our data said.”

But Communication sophomore Ryan Crist, who is bisexual, said he still believes the study is misleading.

“There are a large number of people who are bisexual, and although there are people who use bisexuality as a transition (to hetero- or homosexuality), it doesn’t detract from the fact that I think people have legitimate feelings for both men and women,” Crist said. “It’s not a phase and it’s not necessarily just something someone is going through. It’s just who they are, and you can’t change that fact.”

Regardless of the study’s results, some students said they believe the experiment will prompt more interest in the ongoing discussion about sexual orientation.

“It’s always good to have discussion about sexuality to raise awareness, whatever the findings are,” Pacha said.

Bailey said he wants to conduct follow-up experiments that focus on the psychological, rather than the physical, elements of attraction.

“I’m happy to have the study repeated, and we will probably try to do some modified method of the study,” Bailey said. “We’re trying to now measure sexual arousal in the brain, so we’ll probably do a similar study on the brains of bisexual men someday.”

Reach Allison Bond at [email protected]