時差N小時:咖啡因幻覺

Yael: Time to go again to the A Moment of Sciencemailbag. A listener writes: Dear A Moment ofScience, I recently read about how drinking as manyas seven cups of coffee per day can make mehallucinate. Is this true? I'm a pretty heavy coffeedrinker, so I'd like to know.

雅艾爾：又到了《科學(xué)時刻》讀信時間。一位聽眾寫到：親愛的《科學(xué)時刻》欄目組，近期我讀到一篇文章，講關(guān)于每天喝七杯咖啡如何讓人產(chǎn)生幻覺。這是真的嗎?我是一個重度咖啡飲者，所以我很好奇。

Don: Interesting question. For those that don'tknow, here's some background. Researchers at the University of Durham, in England surveyedtwo-hundred students about their daily consumption of coffee, energy drinks, and othercaffeine products. They asked, among other things, if the students ever experiencedhallucinations. The results appeared to show that students who consumed the equivalent ofseven cups of instant coffee were three times more likely to have heard a disembodied voicethan students who consumed less caffeine. Heavy caffeine users were also more likely tosense the presence of dead people and see things that weren't there.

唐：有趣的問題。先為那些不了解的人來講講背景知識。英國杜倫大學(xué)的研究者們調(diào)查了200名學(xué)生，統(tǒng)計出他們每日消費咖啡、能量飲料還有其它含有咖啡因產(chǎn)品的情況。他們問學(xué)生是否在其它情形下曾產(chǎn)生過幻覺。調(diào)查結(jié)果顯示，攝入大約7杯速溶咖啡的學(xué)生，相比那些攝入較少咖啡因的學(xué)生更有可能聽見一種非實體的聲音，這種可能性是后者的三倍。重度咖啡飲者更有可能感覺到鬼魂的存在，看見正常人看不見的東西。

Yael: As for why caffeine may induce hallucinations, the researchers could only speculate.But they think it might have to do with cortisol—a hormone released during stress. Caffeine isknown to make the body produce even more cortisol during stress.

雅艾爾：至于咖啡因為什么會讓人產(chǎn)生幻覺，研究者只能作出推斷。他們認為也許與皮質(zhì)醇有關(guān)，皮質(zhì)醇是一種激素，人在壓力之下會釋放皮質(zhì)醇。眾所周知，在壓力之下，攝入咖啡因會使人體分泌更多皮質(zhì)醇。

Don: But none of this is solid proof that caffeine triggers hallucinations. First, it's possible thatpeople already prone to hallucinations turn to caffeine as a way to self-medicate. Also, thestudy depended on the subject's self-reporting. The only way to really find out if caffeine hasanything to do with hallucination is to do a random controlled study, where several groupsof subjects consume varying amounts of caffeine and are monitored in a controlled setting.

唐：但這都不足以說明咖啡因能引起幻覺。首先，可能是有幻覺傾向的人把咖啡因當(dāng)做一種自我療法的方式。同時這項研究依賴于主觀報告。找到咖啡因是否與幻覺有聯(lián)系的唯一方式就是進行隨機調(diào)查，讓幾組受試者攝入不同份量的咖啡因，并在可控的環(huán)境里進行監(jiān)測。

Yael: Still, the study is an interesting first step toward learning more about how what we put inour bodies affects the ways we think and behave.

雅艾爾：不過，這項研究在了解身體會如何影響人的思維和行為方式上，邁出了有趣的第一步。