Hand to Mouth

R&D
News of science, technology, and medicine
DISCOVER Vol. 20 No. 3 (March 1999)

What would conversation be like without hand gestures? Difficult, and in countries like Italy, perhaps unimaginable. It was her travels to Italy, in fact, that inspired Jana Iverson, a psychologist at the University of Chicago, to see whether we learn gesturing from others or if it is an innate part of speaking. She asked 24 children, 12 of whom had been blind from birth, to compare the amounts of water in two identical glasses, then compare them again after the water in one glass was poured into a dish. (The blind children explored the water and receptacles with their hands.)

Asked how they arrived at an answer, both blind and sighted children used the same gestures as they spoke, including cupping one hand into a C shape and imitating the act of pouring. Blind children gestured even when talking to an experimenter they knew was blind. "The fact that someone who had never seen gestures before would gesture," says Iverson, "even to a partner who they know can't see, suggests that gesturing and speaking are tightly connected in some very fundamental way in our brains."