Sexist attitudes are linked to depression and anxiety, say researchers. Studies have shown that people who are 'sexist' are angrier, and are more likely to suffer from mental health issues.

Researchers have found a link between 'sex role egalitarianism' and the anatomy of the brain. Those that are more sexist have more brain activity in the posterior cingulate cortex – part of the brain which is involved in dealing with anger – and less brain activity in the right amygdala – used for overcoming depression and anxiety.

The authors of the paper, from Tohoku University in Japan, write: "These findings suggest that variations in sexist stereotypes have roots in the limbic brain structures linked to contentious interpersonal orientation, and negative moods."

The study, published in Nature and lead by Hikaru Takeuch, used 681 healthy participants for the study – 375 men and 306 women – all aged between 18 and 23 years old. Each individual completed a questionnaire, which contained 15 statements. Each statement was followed by a "I don't agree at all" box, to a "I agree very much" box.

The statements included issues of association between men and women in role sharing (for example, housework and cleaning), and attitudes towards the raising of children. The responses to the questionnaire determined a value for each participant's sexist behaviour – or sex role egalitarianism (SRE).

These results were then compared to MRI brain images from the contributors. The scientists noticed that those with a lower SRE score – or the more sexist – had big dense grey matter in the part of the brain which is associated to anger, and had less of this brain activity in the area associated with depression (the right amygdala).

"The results regarding the right amygdala may provide new insight and speculations on how to alleviate stereotype on sex role," write the authors. "The important aspect is to improve mental health problems through a wide range of interventional methods such as aerobic exercise and cognitive training.

"Improving negative moods may prevent sexist stereotyping and may mitigate a wide range of problems associated with lower SRE and stereotypical views."