Kanarek R B, Swinney D
Department of Psychology, Tufts University, Medford, MA 02155.
Appetite. 1990 Feb;14(1):15-27. doi: 10.1016/0195-6663(90)90051-9.
The effects of food snacks consumed in the late afternoon on cognitive performance in college-aged men were investigated in two experiments. The effects of the snacks were tested in the same subjects after they either consumed or skipped lunch. In the first experiment, the calorie-rich snack was a confectionery product, while in the second experiment, the snack was fruit-flavored yogurt. In both experiments, performance on cognitive tasks following consumption of the calorie-rich snack was compared to performance following consumption of a very low calorie snack (lemon-lime flavored diet soda without caffeine). Four cognitive tasks were employed: digit span recall (forward and backward), arithmetic reasoning, reading, and attention. In both experiments, subjects recalled significantly more digits in the backward digit span test and responded significantly faster in the attention task when they had consumed the calorific snack than when they had consumed the diet soft drink. Additionally, in Experiment 2, subjects solved significantly more arithmetic problems and solved these problems in significantly less time after eating a fruit-flavored yogurt than after consuming the diet soft drink. Results of these experiments suggest that a late afternoon energy-containing snack can have positive effects on cognitive performance on tasks that require sustained attention.
在两项实验中，研究了下午晚些时候食用的零食对大学年龄段男性认知表现的影响。在同一组受试者中，分别在他们吃午餐或不吃午餐后测试零食的效果。在第一个实验中，高热量零食是一种糖果产品，而在第二个实验中，零食是水果味酸奶。在两项实验中，将食用高热量零食后的认知任务表现与食用极低热量零食（不含咖啡因的柠檬青柠味无糖汽水）后的表现进行了比较。采用了四项认知任务：数字广度回忆（顺背和倒背）、算术推理、阅读和注意力。在两项实验中，与饮用无糖汽水相比，受试者在食用高热量零食后，在倒背数字广度测试中回忆起的数字明显更多，在注意力任务中的反应也明显更快。此外，在实验2中，与饮用无糖汽水相比，受试者在食用水果味酸奶后解决的算术问题明显更多，且解决这些问题的时间明显更短。这些实验结果表明，下午晚些时候食用的含能量零食对需要持续注意力的任务的认知表现有积极影响。
