From VOA Learning English, this is the Health Report.
Many people say they can not start their day without first having a cup of coffee or tea. People say these drinks help them think clearly and feel more awake. This is because of caffeine, a substance found in some plants.
Caffeine helps to give a jumpstart to the nervous system. Now a new report says it may also improve long-term memory. The report was published earlier this year in the journal Nature Neuroscience.
Caffeine enhances consolidation of long-term memories.
Michael Yassa is a neurobiology professor at the University of California, Irvine. He and other researchers wanted to know if caffeine could improve what they called memory consolidation. They asked a group of individuals to learn something new, then the same people were given caffeine, the active ingredient in coffee, tea and chocolate.
He and the other researchers worked with a group of 160 people who were caffeine free. On the first day, all the subjects were shown pictures of everyday objects. They were asked to identify whether the pictures could be found inside the house or outdoors. Some of the subjects were then given a caffeine pill, the others were given a placebo - a pill containing an inactive substance.
On the second day, all of the subjects were asked to look at more pictures. Some of the images were exactly like the ones they had seen 24 hours early. But other images were different. And a third group of pictures was similar to the first group but a little different. The participants had to decide whether the images they saw were the same or different from the ones on the first day.
Professor Yassa says their answers help to show the effects of caffeine on memory.
He says those who took the caffeine pills had a ten to twelve percent increase in their ability to remember the objects. The amount of caffeine the researchers used in the study was similar to one strong cup of coffee.
Professor Yassa says pills with a little more coffeine also increased memory, but resulted in some participants appearing more nervous.
And that's the Health Report from VOA Learning English. For more stories about health, go to our website learningenglish.voanews.com. I'm Christopher Cruise.
1.caffeine n. [有化][药] 咖啡因；茶精（兴奋剂）
Caffeine is bad for your health.
2.memory consolidation 记忆巩固
He is interested in learning whether they could improve consolidation in people with memory problems.
3.inactive adj. 不活跃的；不活动的；怠惰的；闲置的
He certainly was not politically inactive.
1.Professor Yassa says pills with a little more coffeine also increased memory, but resulted in some participants appearing more nervous.
result in 导致，结果是
The unsatisfiedness of the workmen resulted in a strike.
The football match resulted in goalless draw.
很多人说只有先喝上一杯咖啡或茶，才能开始一天的生活。人们说这样能帮助他们清醒地思考，感觉更清晰 。这是因为这些植物中存在有咖啡因 。
第二天，他们要求所有的实验对象都看更多的图片。有的图片和24小时前他们看到的一模一样，但其他的不一样 。第三组图片和第一组相似，但有轻微不同 。参与者必须决定这些图片和前一天看到的一样还是不一样 。