文字稿

怀孕会减少女性大脑特定区域中灰质的总体积，然而这不仅能加强孕妇与其婴儿之间的联系，还可以帮助产妇适应母亲这个新身份。科学家们对 25 名初孕女性进行了脑部扫描，结果显示她们的大脑在怀孕期间发生了结构性的改变，且这一变化会在产后至少持续两年。请听 Robert Pigott 的报道。

When the brains of 25 first-time mothers were scanned soon after they had become pregnant and again after they had given birth, “substantial” reductions in the volume of grey matter were revealed.

Pregnant women have often complained of brain fog and poor memory, but researchers at Leiden University in the Netherlands and the Autonomous University of Barcelona say that rather than indicating a simple loss of mental capacity or intelligence, the changes represent a pruning and refinement of brain circuits. They say the changes largely affect areas of the brain associated with the ability to attribute thoughts and feelings to oneself and other people, and could help women adapt to motherhood by recognising threats to their baby or anticipating the child’s needs.

Parts of the brain where grey matter had been pruned lit up on MRI scans when mothers saw pictures of their own babies. The brains of first-time fathers did not show such changes in structure.

词汇表

first-time 首次的，初次的
substantial 大量的
volume 体积，总量
grey matter （大脑）灰质
brain fog “脑雾”，指思维不清，反应迟钝的症状
mental capacity 心智，思维能力
pruning 删减、精简的过程
brain circuits 脑回路
attribute 将（品质、特征）归属于
motherhood 母性，母亲身份
recognising 辨识，识别
anticipating 预料

测验

请听报道并回答下列问题。

1. What did the scans of 25 first-time mothers' brains show?

2. According to researchers, what do these changes represent?

3. True or false? There were no obvious changes in first-time fathers' grey matter.

4. Which word in the text means 'the process of polishing and improving something'?

答案

1. What did the scans of 25 first-time mothers' brains show?
The scans of 25 first-time mothers showed "substantial" reductions in the volume of grey matter.

2. According to researchers, what do these changes represent?
According to researchers, rather than indicating a simple loss of mental capacity or intelligence, the changes represent a pruning and refinement of brain circuits.

3. True or false? There were no obvious changes in first-time fathers' grey matter.
True. The brains of first-time fathers did not show such changes in structure.

4. Which word in the text means 'the process of polishing and improving something'?
Refinement.