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From VOA Learning English, this is the Health Report.
Many people say they cannot start their day without first having a cup of coffee or tea. People say these drinks help them think clearly and feel awake. This is because of caffeine, a substance found in some plants. Caffeine helps to give a jump start to the nervous system. Now, a report says it may also improve long-term memory. The report was published in the journal Nature Neuroscience. Mike Yassa is with the University of California in 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. The research team studied 160 people who were caffeine-free. On the first day, these people were shown pictures of everyday objects. They were asked to identify whether the pictures could be found inside the house or outdoors. Some people were then given a pill with caffeine. 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 earlier. But other images were different. Individuals taking the caffeine pills had a 10 to 12 percent increase in their ability to remember objects. The amount of caffeine used in the study was similar to a strong cup of coffee. Mr. Yassa says pills with a little more caffeine also increased memory, but resulted in some people appearing more nervous.