Bigender

Bigender, bi-gender or dual gender is a gender identity that includes any two gender identities and behaviors, possibly depending on context. Some bigender individuals express two distinct "female" and "male" personas, feminine and masculine respectively; others find that they identify as two genders simultaneously. It is recognized by the American Psychological Association (APA) as a subset of the transgender group. A 1999 survey conducted by the San Francisco Department of Public Health observed that, among the transgender community, less than 3% of those who were assigned male at birth and less than 8% of those who were assigned female at birth identified as bigender.

A bigender gender-identity has been described as varying over time between two extremes. These periods can be anywhere from a few hours to a few years and there is no limit to the number of times that it may change. A student at the University of Missouri, Kansas City, described the back and forth shift, saying

Identifying as bigender is typically understood to mean that one identifies as both male and female and/or moves between a masculine gender expression and feminine gender expression with little middle ground. This is different from identifying as genderfluid, as those who identify as genderfluid may not go back and forth between any fixed gender identities and may experience an entire range or spectrum of identities over time.

In 2012, researchers Vilayanur S. Ramachandran and Laura K. Case theorized that the alternation of gender states in bigender people is not just explained by the socially constructed nature of gender. Individuals have reported that switches in gender are typically involuntary and occur when the individual would rather remain in the other gender. In the study, more than half of the bigender people studied reported having "phantom limb" experiences—such as experiencing phantom erections when the body itself did not have a penis. Those that reported feeling these phantom parts rated them as moderate in strength (an average of 2.9 on a 5-point scale). The study also revealed a high number of bigender people with bipolar disorder (9 out of 32). Additionally, ambidextrous handedness occurred at a higher rate in bigender respondents.

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