It's true - babies do direct their mothers

(PhysOrg.com) -- New research into hearing impairment from MARCS Auditory Laboratories at the University of Western Sydney has found mothers significantly change their speech patterns based on how well their babies hear them, which can hinder their children's language development.

The findings were made during a study by PhD student Christa Lam, who was looking into how mothers communicate with hearing impaired babies.

"The most important finding was that infant feedback drives mothers' behaviour," Ms Lam says.

"Babies are not passive recipients; rather they are the ones driving their mothers' behaviour."

Ms Lam made the discovery during an experiment where parents and babies sat in different rooms and interacted through a closed circuit television system.

The researchers reduced the volume of the mother's speech in the baby's room to simulate moderate and profound hearing loss.

As the volume was reduced, the babies reduced their level of interaction with their mothers, leading the mothers to change their speech patterns in an attempt to keep their babies' attention.

Researchers found the mothers' vowels became less clearly distinguished, which can be a problem for infants learning how to speak.

Dr Christine Kitamura, Head of MARCS Baby Lab, says the findings show us what many people already know, that babies have the power to change how we behave.

"But best of all, knowledge from this study can now be applied to current intervention strategies for young babies," Dr Kitamura says.