According to a recent study from the University of Essex, women who are identified as heterosexual ‘very rarely are’. Published in the Journal of Personality and Social Psychology, this research led by Dr. Gerulf Rieger found out that "straight women were strongly sexually stirred up by videos of both attractive men and attractive women". 

Medical Daily included on its report that although previous researches have shown how women can be sexually stimulated by both sexes at varying degrees, the differences in "arousal between straight and gay women has been overlooked". The same point as to where this study comes in.

"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," said Dr. Gerulf Rieger, lead researcher of the study from the University of Essex’s Department of Psychology. 

Based on its findings, the researchers suggested that since women tend to be friendlier, sweeter or more caring in nature, they also tend to become more affectionate. Little do they know, this gives an opportunity for intimacy or even romantic feelings to develop in the long run.

The team used eye tracking devices on over 300 women who were shown daring and nude videos of both genders. Capturing pupil dilation or lack thereof as a response to the sexual stimuli, this was administered to monitor and clearly define the differences in the physiological sexual responses of straight and gay women. 

“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,” Dr. Rieger said in the press release.

Sexual arousal is complex, and doesn't necessarily determine orientation. Thus, some recent discourse has suggested that the commonly accepted truth about men being more sexually rigid than women might not be as "natural" as it is for it is more of a product of our culture than our biology. 

The public is however reminded that these findings should not be generalized because "not all women have fantasies over the same sexes". After all, “men are simple, but women’s sexual responses remain a mystery,” Rieger affirmed.