Increased emotions: The babies' brain activity was monitored during an MRI scan as they listened to various noises.

It is precious 'me time' that many new mothers use to catch up ontelephone calls and conversations.

But the next time your baby has a nap, watch what you say.

For at just three months old, babies can tell human voices from other sounds - and work out when someone is sad. Curiously, happy sounds just wash overthem.

A British study shows that the brain areas devoted to processing speech develop much more quickly than was thought and could lead to new insights into conditions such as autism.

The research team from the Institute of Psychiatry at King’s College London started by getting 21 babies acclimatisedtobrain scanners.

Techniques used included giving their parents a CD to take home with the noise made by the machines.

The youngsters, who were aged from three to seven months, then had their brains scanned as various familiar noises were played while they slept.

The first experiment looked at whether the tots could tell the difference between human and non-human noises.

This revealed that coughing, sneezing, yawning, lappingwater reminiscent ofbath time and the squeaking of toys all activated a part of the brain known to process speech. But human sounds lit it up far more.

The researchers then checked whether the babies' brains reacted differently to happy, sad and neutral noises.

This time, a brain area linked to emotion sprung to life, with crying triggering it more than laughter or neutral sounds, the journal Current Biology reports.

Researcher Evelyne Mercure said it was rare to see such specialised brain regions so early in life.

Co-researcher Anna Blasi added: 'It is probably because the human voice is such an important social cue that the brain shows an early specialisation for its processing.

'This may represent the very first step in social interactions and language learning.'

(Read by Nelly Min. Nelly Min is a journalist at the China Daily Website.)

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(Agencies)

許多新媽媽都很珍惜“獨處的時光”，趁著寶寶休息時打打電話，聊聊天。

但下一次在寶寶打盹時，請注意你聊天時說的話。

因為三個月大的寶寶就能辨別人聲，并能察覺到他人悲傷的情緒。奇怪的是，快樂的聲音對他們影響卻不大。

一項英國研究顯示，負責語音處理的大腦部位的發育比人們所想的要快得多，這一發現可能會對治療自閉癥等疾病有所啟發。

來自倫敦大學國王學院精神病學研究所的研究小組首先讓21名嬰兒逐漸適應大腦掃描儀。

他們所采用的技巧包括給嬰兒的父母一張存有大腦掃描儀發出的聲音的CD，并讓他們在家中播放。

然后研究人員在這些三至七個月大的小孩睡覺時對他們的腦部進行掃描，同時播放各種各樣熟悉的聲音。

在第一個試驗中，研究人員觀察這些幼兒能否區分人類和非人類發出的聲音。

研究發現，咳嗽、打噴嚏、打哈欠、讓人聯想到洗澡的沖水聲、玩具發出的吱吱聲都會激活嬰兒負責語音處理的大腦部位。但是人類的聲音對這一部位的影響尤為明顯。

之后，研究人員查看嬰兒的大腦是否會對快樂、悲傷和平和的聲音做出不同反應。

據《當代生物學》雜志的報道，這一次，和情感相關的大腦區域變得活躍起來，其中哭聲引起的反應比笑聲或平和的聲音引起的反應要大得多。

研究人員伊芙林 梅庫爾說，這么小的孩子就有了專用的大腦區域，實在很罕見。

同一研究組的安娜布拉希補充道：“這很可能是因為人類的聲音是非常重要的社交信號，所以大腦才會這么早就有了處理人類聲音的專門區域。

“也許這代表了人類在社交和語言學習方面邁出的第一步。”

來源：中國日報   編輯：許銀娟