题目材料
Researchers, investigating the link between daily coffee consumption and learning, claim that subjects who consumed one cup of coffee a day for one week (the equivalent of 50 mg per day) exhibited improvements in declarative memory. Furthermore, the study revealed that such improvements were longer-lasting than those witnessed in a control group served decaffeinated coffee (decaffeinated contains negligible amounts of caffeine). After a week of learning a list of facts, the subjects who consumed one cup of coffee were able to recall these facts with significantly more accuracy.
While daily coffee consumption may aid in the process of forming a greater number of short-term memories, and increase the likelihood that these memories will be stored in long-term memory, the study glosses over an important fact. Many exhibit sensitivities to caffeine, including headaches (both migraine and non-migraine), sleeplessness, heightened anxiety and any number of factors that, when working either alone or in tandem, may actually lead to a decrease in the observed link between caffeine and learning. Nonetheless, despite the fact that the study represents a random sampling—and thus any number of subjects can exhibit any number of reactions to caffeine—if enough subjects continue to display signs of improvements in learning, then this result would not be inconsistent with the study's findings.
Still, until the researchers either release more details of this study, or subsequent studies are conducted, the extent to which those with caffeine sensitivity influenced the observed link between coffee consumption and memory will not be fully known.
Based on information in the passage, if a follow-up study had been conducted in which those with caffeine sensitivities were removed, such a study would most likely
- Abe so inconclusive as to require scientists to conduct follow-up studies
- Buncover a connection between improvements in declarative memory and caffeine consumption
- Cprovide scientists little insight into the extent in which those with caffeine sensitivities affected the original study
- Dshow a more pronounced relationship between caffeine consumption and an improvement in declarative memory
- Eneed to determine if those without caffeine sensitivities have similar increases in long-term memory retention as they do in short-term memory retention
显示答案
正确答案: D