生活中想提高记忆力 喝点咖啡吧

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.

如果你想记住什么事情，你或许该给自己的大脑一些咖啡因。但是你在何时给它咖啡因相当重要，这是《自然神经科学》（Nature Neuroscience）在1月13日发布的一份新研究报告中所发现的。研究者们发现，在人们记住一系列图片之后给予他们咖啡因（相较于给予安慰剂的对比组），能够极大地提高记住更细微细节的能力。不过，在你狂灌六杯美式咖啡之前，请先记住最有效剂量是：200毫克的咖啡因——大概是一大杯咖啡中的咖啡因含量——才能起到这个效果。

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.

研究者们让不经常摄入咖啡因的受试者尝试记住一系列图片。然后给予他们咖啡因药丸或安慰剂。24小时之后，咖啡因完全排出体外，这些受试者被要求在一套新的图片中挑出哪些图片在前一天出现过。这里容易出错的地方在于，有些图片只是和之前的图片相类似，但并不完全一样，这意味着受试者必须要回忆起原来那些图片上的某些细节。

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.

结果证明，在辨识和旧有图片类似却又不尽相同的图片方面，咖啡因组的表现比对照组的表现要好得多。这个结果很酷，因为它表明，咖啡因能影响大脑巩固记忆的方式。

“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.”

“我们一直都知道，咖啡因有提高认知力的效果，”该研究报告的作者迈克尔·亚萨（Michael Yassa）说，“但其对加强记忆力、防止遗忘的特定效果却从未在人类身上加以详细地验证过。我们是首次对24小时内咖啡因对减少遗忘所产生的特定效果进行汇报。”

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.

重要的一点是，咖啡因是在记忆力任务之后给予的，而不是之前，这确保了其他和咖啡因相关的因素，如注意力、焦虑或能量等，并不是造成这种现象的原因。

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.”

亚萨补充表示，真正有趣的是，这项研究专注于记忆力的一个更为细枝末节的形式。“如果我们采用一种标准辨识记忆力任务，没有这些个容易混淆的相似点，我们可能发现的结果是，咖啡因没有效果，”他说，“而采用这些相似图片之后，就要求大脑做出更困难的辨识——这就是我们所称之为的‘模式分辨’，在我们的研究中，咖啡因似乎就是加强了这一过程。”

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.”

现在，亚萨和他的团队只需阐述为什么会产生这种咖啡因效果，以及哪部分大脑机制对其负责的问题。“我们可以使用大脑成像技术来解决这些问题，”亚萨说，“我们还知道，咖啡因和长寿联系在一起，也可能对老年痴呆症等认知力衰退疾病具有防护作用。这些都是未来相当重要的问题。”

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

你可以自己尝试一下非正式的咖啡因实验，不过请记住，剂量是200毫克——相当于两小杯咖啡或是一杯星巴克中杯咖啡——这一剂量的效果似乎是最大的。更大的剂量很有可能阻碍学习能力，因为会带来各种副作用（很难知道你到底是处于不安还是焦虑状态）。这项研究无疑是激动人心的，因为它指出了适量咖啡因有助于大脑健康的另一个方面——不仅仅是长期的，更是日常的。