Were there more gay woman than gay men in that study? Shouldn't they have checked the sexual orientation before the experiment(s) and made sure to include a balanced number?
Mooey you make an excellent point. Unfortunately they didn't specify the number of participants that had one sexual preference vs. another. However, the article suggests that they did take sexual preference into consideration. Whether or not they made an attempt to choose a large enough group which contained a diverse spread of sexuality is unknown.
Fifteen healthy male volunteers with normal or corrected-to-normal vision participated in the experiment (age: M = 28.27; SD = 8.30; range 20–47 years). One of the participants was left-handed and all the others were right-handed.
Thirty-two (16 females) healthy volunteers with normal or corrected-to-normal vision participated in the experiment (age M = 24.47, SD = 8.32, range 19–66 years). One of the males was left-handed while all the other participants were right-handed. The EEG data of one male participant were not recorded because of technical problems.
It would seem as though they either are not listing the sexual preferences or did not conduct the study to initially consider the effects of varying sexuality.
Immediately after the SCR and ERP measurements, participants rated their experiences of valence and arousal while viewing the face, body and car stimuli using the SAM (Self-Assessment Manikin ). After this the electrodes were removed and the participants were allowed to clean themselves. Finally, participants completed The Sell Assessment of Sexual Orientation –questionnaire . This questionnaire measures sexual attraction towards males and females, amount of sexual activity with males and females, and sexual identity (homo/heterosexuality). For assessing our participants' sexual orientation, we analyzed answers to an item where the participants were asked to rate their degree of homosexuality on a 7-point scale (1 = not at all homosexual; 7 = extremely homosexual).
I stand corrected. They did list the method they used to determine sexuality. Unfortunately, they did not choose a balance between sexuality. They could've obtained any mix of sexuality and therefore their statement regarding the participants sexual orientation affecting levels of N170 is inconclusive:
Comparison of the results between those participants who considered themselves as 'not at all' homosexual and those who considered themselves as at least slightly homosexually oriented suggested that the participant's sexual orientation might be modulating the N170 responses to nude bodies.
However, the statement suggests that the levels of N170 were different for those who are heterosexual vs. those who are homosexual and varying degrees thereof. A larger study would be needed which ensured the sexuality of each group of participants to validate the claim.
Edited by Daedalus, 6 December 2011 - 10:07 PM.