Thought might not be dependent on language, according to new research published in the Proceedings of the National Academy of Sciences.
A UK team has shown that patients who have lost the ability to understand grammar can still complete hard sums.
This suggests mathematical reasoning can exist without language.
The study undermines the assumption that language is the key quality that makes our thought processes more advanced than those of other animals.
"We are kicking against the claim that it is language that allows you to do other high order intellectual functions," lead research Rosemary Varley, from the University of Sheffield, told the BBC News website. (cont.)