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)

许多新妈妈都很珍惜“独处的时光”，趁着宝宝休息时打打电话，聊聊天。

但下一次在宝宝打盹时，请注意你聊天时说的话。

因为三个月大的宝宝就能辨别人声，并能察觉到他人悲伤的情绪。奇怪的是，快乐的声音对他们影响却不大。

一项英国研究显示，负责语音处理的大脑部位的发育比人们所想的要快得多，这一发现可能会对治疗自闭症等疾病有所启发。

来自伦敦大学国王学院精神病学研究所的研究小组首先让21名婴儿逐渐适应大脑扫描仪。

他们所采用的技巧包括给婴儿的父母一张存有大脑扫描仪发出的声音的CD，并让他们在家中播放。

然后研究人员在这些三至七个月大的小孩睡觉时对他们的脑部进行扫描，同时播放各种各样熟悉的声音。

在第一个试验中，研究人员观察这些幼儿能否区分人类和非人类发出的声音。

研究发现，咳嗽、打喷嚏、打哈欠、让人联想到洗澡的冲水声、玩具发出的吱吱声都会激活婴儿负责语音处理的大脑部位。但是人类的声音对这一部位的影响尤为明显。

之后，研究人员查看婴儿的大脑是否会对快乐、悲伤和平和的声音做出不同反应。

据《当代生物学》杂志的报道，这一次，和情感相关的大脑区域变得活跃起来，其中哭声引起的反应比笑声或平和的声音引起的反应要大得多。

研究人员伊芙林 梅库尔说，这么小的孩子就有了专用的大脑区域，实在很罕见。

同一研究组的安娜布拉希补充道：“这很可能是因为人类的声音是非常重要的社交信号，所以大脑才会这么早就有了处理人类声音的专门区域。

“也许这代表了人类在社交和语言学习方面迈出的第一步。”

来源：中国日报   编辑：许银娟