Learning to talk changes the way we hear speech: McGill study

Research shows growing mastery of oral fluency is matched by increased ability to distinguish different speech sounds

McGill University researchers have confirmed that learning to talk actually changes the way we hear speech sounds.

A study by McGill scientists Sazzad Nasir and David Ostry, Department of Psychology, shows that plasticity in sensory and motor systems is linked.  As a child learns to talk or an adult learns a new language, speech motor learning affects the auditory processing of speech sounds. Nasir and Ostry's findings will appear in the upcoming journal Proceedings of the National Academy of Sciences (PNAS).

In an experiment involving 44 young adults, Nasir and Ostry produced speech learning by using a robotic device that introduced a subtle change in the movement path of the jaw during speech. They found that over time, subjects progressively corrected for the displacement and produced movements that approached those observed normally.

The researchers also found that speech motor learning altered the perception of speech sounds. Control subjects did not show this effect. "Our work proves that people hear the speech sounds differently after motor learning. This confirms speech learning affects not only the motor system but actually changes sensory function," said Ostry. "Learning to talk makes it easier to understand the speech of others."