It's easy to assume using 'proper' language is always better, but a language development expert says parents can relax. By Lisa Salmon.

Is talking to my one-year-old son in 'baby talk' good for his language development, or is it likely to have a negative effect?

Mitsuhiko Ota, from Edinburgh University's School of Philosophy, Psychology and Language sciences, has just led a study into the language development of young children exposed to so-called baby talk. He says: "All in all, there's more evidence that baby talk helps babies and toddlers learn language, rather than hinders the process.

"A number of studies demonstrate that the exaggerated intonation and slow pace of speech that characterise baby talk can aid young children in discovering the sounds, words and sentence structures of the language they hear around them. For example, one study shows that babies as young as seven months can pick up new words from a stream of speech when they're spoken to with a baby-talk-like exaggerated intonation pattern.

"In our recent study, we investigated the effects of baby talk words, such as 'choo-choo' and 'tummy', on infants' language development. It's often said that using words like 'choo-choo' and 'tummy', instead of more proper words like 'train' and 'stomach', can slow down vocabulary development.

"To put this idea to the test, we recorded samples of everyday speech addressed to 47 nine-month-olds and measured how often they heard such baby talk words. We then tracked the vocabulary development of these babies up to the 21st month, and discovered that the more they heard baby talk words with a 'y' ending (such as 'tummy' and 'doggy'), or with repeated syllables (such as 'choo-choo' and 'night-night'), the faster their vocabulary growth was.

"We think this is because words ending in the same sound, and words with repeated sounds, are easier to notice and therefore easier to learn. Once you learn these words, you're also more likely to pick up other words.

"So both the manner of speech and the words we use in baby talk have been shown to be supportive of language development. There's no need to shy away from using baby talk at all."