14．Children whose minds wander might have sharper brains，a research suggests．
A study has found that people who appear to be often distracted （走神） have more"working memory"，giving them the ability to hold a lot of information in their heads and control it cleverly．
Children at school need this type of memory on a daily basis for a variety of tasks，such as following teachers'instructions or remembering dictated （听写的） sentences．During the study，volunteers were asked to perform one simple task during which researchers kept asking if their minds were wandering．At the end，volunteers measured their working memory capacity （容量） by their ability to remember a series of letters mixed with simple maths questions．
Daniel Levinson，a professor at the University of Wisconsin-Madison in the United States，said that those with higher working memory capacity reported"more mind wandering during these simple tasks"，but their performance did not suffer．
The results，published online in the journal Psychological Science，appear to confirm former research that found working memory allows humans to deal with multiple thoughts at the same time．
Dr Jonathan Smallwood，of the Max Planck Institute for Human Cognitive and Brain Science in Leipzig，Germany，said，"What this study seems to suggest is that，when surroundings for the task aren't very difficult，people with additional working memory capacity use them effectively to think about other things besides what they're doing．"
Working memory capacity is also associated with general measures of intelligence，such as reading comprehension and IQ scores．Dr Smallwood added："Our results suggest the sorts of planning that people do quite often in daily life-when they are on the bus，when they are cycling to work，when they are in the shower-are probably supported by working memory．"
28．During the study，the researchers asked the volunteers toD．
A．solve some difficult math's problems
B．retell some dictated sentences
C．follow the teacher's instructions
D．carry out one simple task
29．The underlined word"suffer"in the fourth paragraph probably meansA．
A．become worse B．settle down C．experience pain D．run out
30．According to the study，working memoryC．
A．prevents people from remembering dictated sentences
B．causes people's minds to wander more easily
C．allows people to consider more things at the same time
D．leads to people's worse performance during work
31．What's the text mainly about？B
A．How the working memory works in the daily life．
B．Wandering minds might have brighter brains．
C．Why people's minds wander while working．
D．Working ability can be improved by wandering minds．
分析 本文属于说明文阅读，作者通过这篇文章主要向我们描述了研究表明，走神的孩子可能头脑更敏锐，适当的走神其实并不会影响生活．
解答 28．D．细节理解题．根据第二段such as following teachers'instructions or remembering dictated （听写的） sentences．During the study，volunteers were asked to perform one simple task during which researchers kept asking if their minds were wandering可知研究期间，研究人员要求志愿者执行一个简单的任务；故选D．
29．A．词义猜测题．根据第四段said that those with higher working memory capacity reported"more mind wandering during these simple tasks"，but their performance did not suffer可知在这些简单的任务中，他们走神了"，但他们的表现并没有受到影响；可知意为变得糟糕；故选A．
30．C．细节理解题．根据倒数第二段What this study seems to suggest is that，when surroundings for the task aren't very difficult，people with additional working memory capacity use them effectively to think about other things besides what they're doing可知根据研究，工作记忆允许人同时考虑更多的事情；故选C．
31．B．推理判断题．根据第一段Children whose minds wander might have sharper brains，a research suggests可知课文主要是关于走神的大脑可能有更聪明的头脑；故选B．
点评 考察学生的细节理解和推理判断能力，做细节理解题时一定要找到文章中的原句，和题干进行比较，再做出正确的选择．在做推理判断题不要以个人的主观想象代替文章的事实，要根据文章事实进行合乎逻辑的推理判断．
