喝咖啡有助于提高記憶力

If you’re trying to commit a set of items to memory, you may want to give your brain a bit of caffeine. But how you time it matters, finds a new study out today in Nature Neuroscience. The researchers found that giving people caffeine after they memorized a series of pictures significantly boosted their ability to remember the subtler details, compared to people who’d been given dummy pills. Before you down a six-shot Americano, though, be aware that there’s a sweet spot: A 200-milligram dose of caffeine – about the amount in a large cup of coffee – was the only one to do the trick.

如果你想記住什么事情，你或許該給自己的大腦一些咖啡因。但是你在何時(shí)給它咖啡因相當(dāng)重要，這是《自然神經(jīng)科學(xué)》(Nature Neuroscience)在1月13日發(fā)布的一份新研究報(bào)告中所發(fā)現(xiàn)的。研究者們發(fā)現(xiàn)，在人們記住一系列圖片之后給予他們咖啡因(相較于給予安慰劑的對(duì)比組)，能夠極大地提高記住更細(xì)微細(xì)節(jié)的能力。不過(guò)，在你狂灌六杯美式咖啡之前，請(qǐng)先記住最有效劑量是：200毫克的咖啡因——大概是一大杯咖啡中的咖啡因含量——才能起到這個(gè)效果。

The researchers had participants – who were not regular caffeine consumers – try to memorize a series of pictures. Afterwards, they were given a caffeine pill or a placebo (dummy) pill. Twenty-four hours later, when the caffeine was fully out of their systems, they were asked to determine which pictures in a new set had also been shown the day before. The tricky part was that some of the new items were similar but not identical to the old ones, meaning that the participants had to recall the initial items in some amount of detail.

研究者們讓不經(jīng)常攝入咖啡因的受試者嘗試記住一系列圖片。然后給予他們咖啡因藥丸或安慰劑。24小時(shí)之后，咖啡因完全排出體外，這些受試者被要求在一套新的圖片中挑出哪些圖片在前一天出現(xiàn)過(guò)。這里容易出錯(cuò)的地方在于，有些圖片只是和之前的圖片相類(lèi)似，但并不完全一樣，這意味著受試者必須要回憶起原來(lái)那些圖片上的某些細(xì)節(jié)。

It turned out that people in the caffeine group were much better than their non-caffeinated counterparts at recognizing the new items that were similar but not the same as old ones. And this is cool because it suggests that caffeine may influence how the brain consolidates memories.

結(jié)果證明，在辨識(shí)和舊有圖片類(lèi)似卻又不盡相同的圖片方面，咖啡因組的表現(xiàn)比對(duì)照組的表現(xiàn)要好得多。這個(gè)結(jié)果很酷，因?yàn)樗砻?，咖啡因能影響大腦鞏固記憶的方式。

“We’ve always known that caffeine has cognitive-enhancing effects, ” said study author Michael Yassa, “but its particular effects on strengthening memories and making them resistant to forgetting has never been examined in detail in humans. We report for the first time a specific effect of caffeine on reducing forgetting over 24 hours.”

“我們一直都知道，咖啡因有提高認(rèn)知力的效果，”該研究報(bào)告的作者邁克爾·亞薩(Michael Yassa)說(shuō)，“但其對(duì)加強(qiáng)記憶力、防止遺忘的特定效果卻從未在人類(lèi)身上加以詳細(xì)地驗(yàn)證過(guò)。我們是首次對(duì)24小時(shí)內(nèi)咖啡因?qū)p少遺忘所產(chǎn)生的特定效果進(jìn)行匯報(bào)。”

A key aspect was the caffeine was administered after the memory task, rather than before it, which ensures that other caffeine-related factors, like attention, anxiety or energy are not what’s driving the phenomenon.

重要的一點(diǎn)是，咖啡因是在記憶力任務(wù)之后給予的，而不是之前，這確保了其他和咖啡因相關(guān)的因素，如注意力、焦慮或能量等，并不是造成這種現(xiàn)象的原因。

Yassa added that what’s really interesting is that the study focuses on a more detailed form of memory. “If we used a standard recognition memory task without these tricky similar items, we would have found no effect of caffeine, ” he said. “However, using these items requires the brain to make a more difficult discrimination — what we call pattern separation, which seems to be the process that is enhanced by caffeine in our case.”

亞薩補(bǔ)充表示，真正有趣的是，這項(xiàng)研究專(zhuān)注于記憶力的一個(gè)更為細(xì)枝末節(jié)的形式。“如果我們采用一種標(biāo)準(zhǔn)辨識(shí)記憶力任務(wù)，沒(méi)有這些個(gè)容易混淆的相似點(diǎn)，我們可能發(fā)現(xiàn)的結(jié)果是，咖啡因沒(méi)有效果，”他說(shuō)，“而采用這些相似圖片之后，就要求大腦做出更困難的辨識(shí)——這就是我們所稱(chēng)之為的‘模式分辨’，在我們的研究中，咖啡因似乎就是加強(qiáng)了這一過(guò)程。”

Now the and his team just have to unravel why the caffeine effect occurs at all, and which brain mechanisms are responsible. “We can use brain-imaging techniques to address these questions, ” said Yassa. “We also know that caffeine is associated with healthy longevity and may have some protective effects from cognitive decline like Alzheimer’s disease. These are certainly important questions for the future.”

現(xiàn)在，亞薩和他的團(tuán)隊(duì)只需闡述為什么會(huì)產(chǎn)生這種咖啡因效果，以及哪部分大腦機(jī)制對(duì)其負(fù)責(zé)的問(wèn)題。“我們可以使用大腦成像技術(shù)來(lái)解決這些問(wèn)題，”亞薩說(shuō)，“我們還知道，咖啡因和長(zhǎng)壽聯(lián)系在一起，也可能對(duì)老年癡呆癥等認(rèn)知力衰退疾病具有防護(hù)作用。這些都是未來(lái)相當(dāng)重要的問(wèn)題。”

You can do an informal caffeine experiment on yourself, but again, remember that it’s the 200 mg dose – the equivalent of about two small cups or one tall Starbucks

你可以自己嘗試一下非正式的咖啡因?qū)嶒?yàn)，不過(guò)請(qǐng)記住，劑量是200毫克——相當(dāng)于兩小杯咖啡或是一杯星巴克中杯咖啡——這一劑量的效果似乎是最大的。更大的劑量很有可能阻礙學(xué)習(xí)能力，因?yàn)闀?huì)帶來(lái)各種副作用(很難知道你到底是處于不安還是焦慮狀態(tài))。這項(xiàng)研究無(wú)疑是激動(dòng)人心的，因?yàn)樗赋隽诉m量咖啡因有助于大腦健康的另一個(gè)方面——不僅僅是長(zhǎng)期的，更是日常的。