There’s plenty of research out there about how learning a new language can change the way you think. But in a small study recently published in the journal Frontiers in Psychology and highlighted by Mental Floss, a team of researchers from the U.K. added a twist: When the new language in question is a visual one, it can change your sight, too.
For the study, a team of researchers in the U.K. recruited three groups of people — some who had been born deaf, some people with their hearing intact who knew British Sign Language, and some who could hear and didn’t know sign language — to complete a computer task that tested their vision and reaction time.
Across the board, the deaf people fared best, a result that surprised no one: “These findings support the common belief in sensory compensation,” lead author Charlotte Codina, a vision researcher at the University of Sheffield, said in a statement. Scientists have long known that when one of the five senses doesn’t work properly, the other four will kick into overdrive to pick up the slack.
More surprising, though, was the the fact that the second group — the hearing people who knew BSL — also fared better than those who didn’t know how to sign. “These results suggest that fluency in sign language requires or builds visual-processing skills that non-signers don’t have,” Mental Floss explained, “and that adulthood is not too late to learn and benefit from the language.” Vision, in other words, is a bit like a muscle, something that can be toned and strengthened over time.