It leaves those with the condition sensing ‘phantom genitalia’ of the opposite sex.
A group of people with the previously undiagnosed ‘alternating gender incongruity’ (AGI) said they can switch involuntarily from male to female and vice versa instantly.
'The majority of bigender individuals experience phantom breasts or genitalia corresponding to the non-biologic gender when they are in a trans-gender state’, according to the astonishing survey by a respected neuroscientist.
’I sometimes wake up thinking I have a penis,’ says one female respondent, ‘or that I have no breasts.
'I usually end up in tears and I can’t get out of bed because once I get up I’ll know for sure it’s not really true and it’s just my mind playing tricks on me, so I just lie there and cry.
'It’s strange though because I normally don’t even want to have a penis.’