2012届高考二轮复习英语学案：第25讲信息的表述（湖南专用31讲）_高考复习指南

2012届高考二轮复习英语学案：第25讲信息的表述（湖南专用31讲）

　　第25讲

　　信息的表述

　　(湖南省长沙市一中2011 届高三月考七)According to the surprising findings of a new study by U. S. investigators, chewing sugarless gum during class and while doing homework can have a positive effect on academic performance in teenagers.

　　Study leader Craig A. Johnston of the Children's Nutrition Research Center at Baylor College of Medicine in Houston, Texas, and his colleagues studied more than 100 eighthgrade students, 52 girls and 56 boys, aged between 13 and 16 years, in four math classes. The experts randomly(任意地) assigned teenagers into two groups: one group was asked to chew Wrigley's sugarfree gum during class, while doing homework, and also while performing a standardized test. They chewed at least one stick of gum 86 per cent of the time they were in math class and 36 per cent of the time they were doing homework. The participants of the other group did not.

　　Johnston and his team found that 14 weeks later, the gum chewers had a 3 percent increase in their math scores on the Texas Assessment of Knowledge and Skills achievement test,

　　a small but statistically significant change, according to experts. There was no difference found in math scores between the participants in the two groups in another test called the Woodcock Johnston Ⅲ Tests of Achievement.

　　However,

　　the experiment revealed(展现) that gumchewers had better final grades in the class compared to their nonchewing peers(同龄人). According to Johnston, chewing gum reduces stress and anxiety as well as it increases arousal(兴奋).