Research into how hormone treatment in transsexual women undergoing sex changes affects thought processes has shown that some stereotypes about the difference between men’s and women’s brains really are true.

Woman talks on mobile phone
Hormones make women better at effective chatting (Lauren Hurley/PA)

Scientists have found that giving testosterone to women as they go through the change makes them start to “think more like men”. This is because the treatment leads to structural changes in the brain, including a shrinking in the parts that are key for language.

In other words, it suggests that women’s brains really are naturally wired to make them better (in general) at verbal skills and multi-tasking, while men, scientists say, are usually believed to have better spatial awareness. Usually.

Cars badly parked
If it’s wired into the brain, what’s the excuse for this? (Jason Thien/Flickr)

So maybe men are from Mars and women are from Venus, after all.

All this was found when a team of scientists put 18 female-to-male transsexuals through an MRI (magnetic resonance imaging) brain scan and actually found that exposure to the male hormone reduced the number of nerve cells (aka grey matter) in Broca’s and Wernicke’s areas – the regions linked to language processing – but strengthened the connection between the two.

So, aside from the scientific jargon, what have we actually learned here? We’ve always been used to the idea that men and women often just seem to come from different planets. So what’s new?

School pupil writing
We already know that differences between boys and girls develop with maturation (Dave Thompson/PA)

Dr Kamilla Miskowiak, of Copenhagen University Hospital, explains: “These findings may suggest that the genuine difference between the brains of women and men is substantially attributable to the effects of circulating sex hormones. Moreover, the hormonal influence on human brain structure goes beyond early developmental phases and is still present in adulthood.

“It is well known that language development differs between girls and boys and that this is related to gender-related differences in brain maturation.

Art piece featuring real human brain suspended in drawing of a human head
Differences between men’s and women’s thought processes could be in the brain all along (Ben Birchall/PA)

“However, this intriguing neuroimaging study of transsexuals before and after their female-to-male gender reassignment suggests that even adult men and women differ in brain structure within regions involved in language and speech.”

So we’ve also learned that discoveries relating to natural differences between men’s and women’s brains are being made more possible than ever by studying the transsexual population.

Professor Rupert Lanzenberger, of the University of Vienna, said: “What we see is a real quantitative difference in brain structure after prolonged exposure to testosterone. This would have been impossible to understand without looking at a transsexual population.”

The findings were presented at the annual meeting of the European College of Neuropsychopharmacology (ECNP) in Amsterdam, the Netherlands.