加拿大的Waterloo大学（University of Waterloo）的科学研究结果（研究论文网址：https://ryugaku-kuchikomi.com/blog/ebbinghaus-the-forgetting-curve/，因为有时候可能打不开，所以我把英文论文附在了文章的最后），似乎找到了复习的最佳时间点。
首先请看下面的图：
黑色线是你的记忆。
最初，你开始什么都不知道的学习，学到了知识，这个时间点的记忆是100%成立的。
但是你没有复习，黑色线代表的就是你的遗忘。
当然，这和遗忘曲线的感觉是一样的。
可是你复习了，你记住了所学的知识，那么请看图中的黄色线。
“先是学习后的24小时内的10分钟复习，记忆率会100%恢复；然后，从这才是才是真正的让人兴奋，因为下次的复习方法1周内，只要5分钟就能让100%的记忆苏醒；再之后，也就是1个月内，你只要用2~4分钟的时间再度复习，那么记忆就会再度复活；到这里，记忆几乎已经变成了长期记忆，可以许久不忘。”
只要这个复习的时机没有出错，那么最大只要19分钟的复习就能让你当天所学在1个月后也遗忘不了。
如果是学生的话，课后1天内，1周内，1个月内进行复习，那么在平时的小测试和期末考试时，大部分的知识都还能记住。
因为其实所要时间很短，所以平日的碎片时间就可以利用起来，最好的是在睡前的快速复习。
如果做不到在这些时间点进行复习，那么今后在考试前要做的复习将会和最初学习时一样的感觉，差不多就是新学。
毕竟遗忘曲线也告诉了我们，1个月后80%的记忆都将不复存在。
并且，像这样分几次的复习（其实说的就是高效学习的基本方法的分散学习），更利于长期记忆的形成。
如果你是高中生，你的记忆不会只是为了平日的考试或者期中期末考试，肯定也想把这些记忆留存到高考的时候；如果你在学英语或者考证书，那么当然希望所学知识能在今后的长期期间内都能是可以被活用的状态，那么就遵守这个复习的时间点来复习，相信会非常有效。
附原文：
Curve of Forgetting
The Curve of Forgetting describes how we retain or get rid of information that we take in. It"s based on a one-hour lecture.
Graph illustrating the curve of forgetting
On day 1, at the beginning of the lecture, you go in knowing nothing, or 0%, (where the curve starts at the baseline). At the end of the lecture you know 100% of what you know, however well you know it (where the curve rises to its highest point).
By day 2, if you have done nothing with the information you learned in that lecture, didn"t think about it again, read it again, etc. you will have lost 50%-80% of what you learned. Our brains are constantly recording information on a temporary basis: scraps of conversation heard on the sidewalk, what the person in front of you is wearing. Because the information isn"t necessary, and it doesn"t come up again, our brains dump it all off, along with what was learned in the lecture that you actually do want to hold on to!
By day 7, we remember even less, and by day 30, we retain about 2%-3% of the original hour! This nicely coincides with midterm exams, and may account for feeling as if you"ve never seen this before in your life when you"re studying for exams - you may need to actually re-learn it from scratch.
You can change the shape of the curve! Reprocessing the same chunk of information sends a big signal to your brain to hold onto that data. When the same thing is repeated, your brain says, "Oh - there it is again, I better keep that." When you are exposed to the same information repeatedly, it takes less and less time to "activate" the information in your long term memory and it becomes easier for you to retrieve the information when you need it.
Here"s the formula and the case for making time to review material: within 24 hours of getting the information - spend 10 minutes reviewing and you will raise the curve almost to 100% again. A week later (day 7), it only takes 5 minutes to "reactivate" the same material, and again raise the curve. By day 30, your brain will only need 2-4 minutes to give you the feedback, "yes, I know that..."
Often students feel they can"t possibly make time for a review session every day in their schedules - they have trouble keeping up as it is. However, this review is an excellent investment of time. If you don"t review, you will need to spend 40-50 minutes re-learning each hour of material later - do you have that kind of time? Cramming rarely stores information in your long term memory successfully, which makes it harder to access the material for assignments during the term and exam preparation.
Depending on the course load, the general recommendation is to spend half an hour or so every weekday, and 1.5 to 2 hours every weekend in review activity. Perhaps you only have time to review 4 or 5 days of the week, and the curve stays at about the mid range. That"s ok, it"s a lot better than the 2%-3% you would have retained if you hadn"t reviewed at all.
Many students are amazed at the difference reviewing regularly makes in how much they understand and how well they understand and retain material. It"s worth experimenting for a couple weeks, just to see what difference it makes to you!
