Gender inequality ‘shrinks women’s brains’ by causing chronic stress

Difference in grey matter is greater in countries where females have fewer rights, researchers find

GENDER inequality may shrink women’s brains, research has suggested.

A study by the University of Oxford that looked at scans of more than 7,800 people aged 18 to 40 found significant brain thinning in women living in countries with fewer female rights and maledominated cultural norms.

In countries where there was greater gender inequality, such as India, Turkey and Brazil, the thickness of the grey matter in the right hemisphere of women’s brains was up to 5 per cent thinner than men’s.

However, in Scandinavian countries such as Sweden and Finland, there was no significant difference between the sexes, with women showing thicker grey matter than men in some areas.

In Britain, researchers found about 0.5 per cent thinning in the right hemisphere of female brains, which they say could be a result of gender inequality.

The areas of the brain affected – the anterior cingulate cortex and orbitofrontal cortex – are linked to stress and emotions. Researchers believe that living in unequal environments may cause chronic stress that damages the connections between brain cells and shrinks the grey matter. Lack of opportunities in school or at work may also prevent the development of brain connections, the researchers suggested.

Experts said the level of brain thinning was similar to that seen in people with conditions such as schizophrenia.

Dr Nicolas Crossley, the lead author, who is a visiting professor in the department of psychiatry at the University of Oxford and an associate professor at the Pontificia Universidad Católica in Chile, said: “Our analysis suggests some sex differences in brain structure are associated with the adverse social environment under which many women live.

“These changes were particularly located in regions involved in control of emotions and that are also affected in stress-related disorders such as depression and post-traumatic stress disorder.

“We therefore think that what we are seeing is the effect of chronic stress in women’s brains in gender unequal environments. Stress affects neurons’ connections, which we would then see as thinning of the grey matter cortex in MRI studies.

“However, other mechanisms could also be involved, such as the effect of reduced opportunities including education in women’s brains, leading to lower development of connections.”

The study was published in the journal Proceedings of the National Academy of Sciences in collaboration with more than 70 other institutions.