London, March 6 (IANS): People are quicker to categorise a face as being male when it is shown to the left side of the brain, reveals a new study.

"Our study clearly found that people are much more likely to make a quick decision that a face is male when it is shown to the left-hand side of the brain," said lead study author Sapphira Thorne from the University of Surrey.

The researchers analysed the responses from 42 volunteers, who were asked to focus on a cross in the centre of a computer screen.

They were then shown faces, which were morphed from 100 percent male to 100 per cent female across 280 trials, and were asked to categorise these faces as either female or male as quickly as possible.

The team found that when an image was presented to the left side of the brain, it was generally considered more male, even though it was correctly perceived as more female when presented to the right side of the brain.

Previous research from the University of Surrey has already found that English language speakers place males ahead of females in sentences, in part due to gender stereotyping.

The new research, which was carried out in English on English-speaking volunteers, showed that a bias to perceive faces as male in the English language affects the way that we perceive other people's faces, because the left side of the brain is the side which processes language.

"It is important to recognise that our split second judgments about another person's gender are not always correct, and we should be aware of our ability to unconsciously judge and categorise people.

"In a society that increasingly recognises transgender people's rights to define their own gender identities, relying on our stereotypes to judge others' genders could lead to discrimination," Thorne said.

The study was published in the journal Laterality.