Brains built for grammar: study

The properties of grammar may be be hard-wired in our brains, according to a study of people who are deaf and isolated from conventional language.

Young children normally learn language through exposure to a spoken or signed language, as well as their innate abilities to acquire certain types of language patterns.

To tease out the effect of each influence, researchers turn to people who aren't exposed to conventional language.

For three years, researchers at the University of Rochester studied three young men in Nicaragua who were completely deaf since birth.

The men had no exposure to formal sign language, never had contact with another signer and weren't exposed to written Spanish in school. Nevertheless, the boys developed a unique form of gesture communication.

"Our findings suggest that certain fundamental characteristics of human language systems appear in gestural communication, even when the user has never been exposed to linguistic input and has not descended from previous generations of skilled communicative partners," said Elissa Newport, a professor of brain and cognitive sciences and linguistics.

Newport and her colleagues found the signers used the same rules of grammar as other users of language, such as the grammatical concept of a "subject."

The signers were tested by watching 66 short videos of actions, such as a woman walking. Researchers asked the boys to explain what they had seen in their own sign language.

The findings suggest the "grammatical concept of 'subject' is part of the bedrock in which languages form," Newport said.

The study appears in the Proceedings of the National Academy of Sciences.