All in the mind: Could the study hint at a predetermined image of our gender that we have in our minds before birth?
CANBERRA: Similar to the phantom limb syndrome, the sensation of a 'phantom penis' in post-operative heterosexual and transsexual men is providing insights into the how gender-specific body images are hard-wired at birth.
Experts at the University of California in San Diego, USA, found that 60 per cent of interviewed heterosexual men who had their genitals surgically removed following cancer claimed to continue to experience the sensation of having a penis.
Presence of phantoms
Intriguingly, the same study showed that only 30 per cent of originally male transsexuals, whose genitals had been removed as part of gender reassignment, reported the same phenomenon.
"We explain the absence or presence of phantoms in these subjects by postulating a hardwired gender-specific body image in the brain that does not match the external [birth] gender" said lead author and phantom limb expert Vilayanur Ramachandran. He argues that before birth the brain may develop an image of the body that may not necessarily match the physiological outcome.
The research was reported by psychologist and co-author Paul McGeoch at the 2007 meeting of the Cognitive Neuroscience Society held in New York City, and is scheduled for publication in the Journal of Consciousness Studies.
Surgically removed
To collect data, the researchers interviewed men who had their penises removed in surgery – either as a medical necessity following genital cancer or as part of gender reassignment surgery. But they also interviewed female-to-male transsexuals.
The survey showed that aside from the fact that male-to-female transsexuals were less likely to report the phenomenon of a phantom penis than heterosexuals, 60 per cent of female-to-male transsexuals interviewed reported the sensation of phantom penises since early childhood.
The experts argue that the study adds to the evidence that body images of gender are hard-wired before birth, and may also hint at a biological basis – one that is predetermined before birth – for why many transsexuals claim to feel a mismatch between their 'gender identity' and the sex that they were born.
While still preliminary, the theory is based on existing knowledge that much of the way we perceive our body is from innate hard-wiring of our brains during embryo development.
Gender identity mismatch
A mismatch between body image and reality has long been documented in some amputees who continue to report the sensation of having a limb after it has been removed – and even in people born without limbs. Phantom limbs are purported to be the result of 'cross-wiring' in the nerves of the brain responsible for the missing limb and surrounding brain regions, said the researchers.
The phantom penis phenomenon is thought to be caused by a similar process, and results in patients without a penis still being able to describe its shape and length and experience 'phantom erections'.
However, not everyone agrees about the conclusions drawn from the results. Psychologist Barbara David, an expert on gender at the Australian National University in Canberra, argues that the study takes its conclusions from the data too far.
"The researchers interviewed transsexuals and can be scientific about what the transsexuals feel. This, however, provides no link with hardwiring of the brain," she said.
