Human sexuality, it appears, has never been more complex.
Not to mention elusive.
A scientist has studied a group of men and women who report that their sexual identity can switch involuntarily to that of the opposite sex and back again, Scientific American reports.
For some people, the switch can occur several times a day.
Most of them however, report the frequency is more like once a week.
The “switch” is accompanied by the sensation of phantom breasts or genitalia of the non-biological sex.
The study, Medical Hypotheses, “Alternating gender incongruity: A new neuropsychiatric syndrome providing insight into the dynamic plasticity of brain-sex,” was published by Laura Case, a graduate student of renowned neuroscientist Vilayanur S. Ramachandran.
It is based on research with 32 respondents (11 anatomically female) from an online bigender forum that hosts about 600 members.
Scientific American listed the following fascinating quotes from research subjects: