Toronto, Oct 28 (IANS): For ages lullabies have been known to keep infants quiet and lull them into nodding off. Now research has backed up tradition by finding out that playing a song or singing nursery rhymes can keep babies composed for longer than talking to them.

The infants in the study remained calm twice as long when listening to a song, which they did not even know, as they did when listening to speech.

"Our findings leave little doubt about the efficacy of singing nursery rhymes for maintaining infants' composure for extended periods," said one of the researchers Isabelle Peretz, professor at University of Montreal in Canada.

The study involved thirty healthy infants aged between six and nine months. They compared the effects of singing, baby talk and adult-directed speech on the composure of the infants.

The researchers took a variety of measures to ensure the children's reaction to the music was not influenced by other factors, such as sensitivity to their mother's voice.

Both the speech ("baby talk" and adult-directed) and the music presented to infants were produced in Turkish, so that the song and language were unfamiliar.

The researchers played the recordings until the infants displayed the "cry face" - lowered brows, lip corners pulled to the side, mouth opening and raised cheeks.

This is infants' most common facial expression of distress.

"When listening to the Turkish song, babies remained calm for an average duration of approximately nine minutes. For speech, it was roughly only half as long, regardless of whether it was baby-talk or not," study first author Marieve Corbeil, also of the University of Montreal, pointed out.

"These findings speak to the intrinsic importance of music, and of nursery rhymes in particular, which appeal to our desire for simplicity, and repetition," Corbeil explained.

The study was published in the journal Infancy.