How to Remember What You Read — The Tool You Always Had But Ignored
Besides the tips and tricks, sleeping is the single most important tool
I'm not the first one and neither I'll be the last writing about how to remember things you read. There are a ton of tools on the internet that helps us achieve that. But I’ve realized something while reading and watching videos from Matthew Walker, the sleep scientist, and professor of neuroscience and psychology at UC Berkeley, and from my personal experiences that sleep is the single most powerful yet neglected tool that we have.
I'm not sure why but maybe we just take sleep for granted. It is something that we all have access to but yet we are on a constant search to find new tools. Don't get me wrong, I love a good life hack, but before we go out in the wild looking out for something different, we may just focus on doing the basics properly.
In this article, I’ll explain how sleep is the single best tool — inspired by the book “Why We Sleep” by Matthew Walker — and will give you some tips that I personally find useful and are simple and engaging enough that anybody can be motivated to use them. Before going into the "How to" part, let's talk about how we retain information.
The forgetting curve
Over time, information is lost if we don't try to retain it. That's what Hermann Ebbinghaus, a German psychologist, found out in the 19th century. So if you finish reading a book today and you don't find a way to try to retain it, you will probably forget what you read.
How can we combat it? There are four key elements to this:
- Reinforcing the information regularly will make it easier to recall and will reduce the rate of decline of the curve;
- Make it clear, so it will be easier to absorb and remember later on;
- Make it relevant, then it will be more meaningful for you;
- Make it interactive, because people learn better when they get involved in something.
By addressing those key elements, will help make the graph above look more like this:
This is probably the most important one and yet the most neglected. Everybody knows that getting enough sleep consistently — between 7 and 9 hours — is good for your health, and it’s the cornerstone of absorbing and retaining new knowledge.
As described in Walker’s book, sleep affects our ability to learn and retain new information. It is the single most effective way to create a memory.
Sleep to remember
This is like a save button. By getting enough sleep after learning something new, sleep protects that newly acquired information and consolidates in your brain. In essence, it will transfer the new knowledge from the short-term storage to the long-term one.
In 1924, two German researchers, John Jenkin and Karl Dallenbach did an experiment to see which one was better for memory, sleep or stay awake. In this study, they set students to learn a list of verbal facts, and then they tracked how fast they would forget these facts in an interval of eight hours, where one group slept and the other stood awake for that same period of time. What they found out was that the group of students that slept for eight hours cemented the information better than those that stood awake.
This experiment had been replicated several times over the years and it is known that sleeping can have a memory retention benefit of between 20% to 40% compared to the same amount of time spent awake. And how does this happen?
Basically, sleep helps carry the information from the temporary storage unit in the brain (hippocampus), to a more permanent one (the cortex). This process repeats every night, moving the newly acquired information to the long-term memory, cleaning out the cache of your short-term memory.
Sleep to forget
It is well known that sleep helps create and consolidate memory, but what about before learning something new? Sleep helps you delete information that we no longer need, and lower our brain resources required to retrieve information that we want to retain.
In 2009, Matthew Walker and his student did an experiment to test a hypothesis brought by Francis Crick in 1983, a Nobel Prize Winner neuroscientist, that the function of dreaming was to remove unwanted copies of information in our brain.
They took two groups of participants and presented them on a computer screen, one at a time, a long list of words. After each word, the letter “R” or “F” was presented, indicating if the participant should remember the word presenting earlier (letter “R”) or forget it (letter “F”). One group was allowed to take a ninety minutes nap and the other one stood awake.
The group that took the nap boosted the retention of the words that were supposed to be remembered and avoided the retention of the words that were tagged to be forgotten.
Now that you know the importance of sleep, let me present you with two tools that I like to use. The first one I use on an everyday basis and the second few times a week.
Highlight and review
Highlighting it's a good way to start, but highlighting itself won't help you to remember. You may have done the same thing when you were in college. You've highlighted almost the entire textbook but you've never found it useful, neither helped you remember the things in the book. But highlighting and finding a way to review them over time is very powerful.
There are two tools that can be used and it will depend whether you read on Kindle or on a physical book. Readwise for the former and post-it for the latter.
Readwise it's a service that can connect to your Amazon account and will collect all the highlights from all your books. Then it will send you by email or you can see in their app, 5 random highlights from your books so you can read and recall them every day. I'm not been paid to promote their service but I truly find it very useful and most importantly, adds value to my life.
If you are not into digital reading, obviously you cannot use Readwise. An alternative for the physical world is using post-its. It's not as practical and convenient as the previous solution but the advantage here is that you will be more mindful about what you highlight and writing down will reinforce learning and retention.
Write it down
Coming across your highlights regularly is a great way to remember and absorb the knowledge provided by the book. If you want to maximize your learning and the ability to retain the content from your books, a great way to do so is to write them down. It will force you to be more selective with the highlights and be more engaged with the content.
If you like writing, this is a good way of remembering what you read. It is not simply copying and pasting things from the book, but writing with your own words. Ok, you may not find it motivational or useful to write a summary of the book to just sit on your computer, and personally, I don't find it either. A great way to get some motivation is to write not simply a resume, but your thoughts and insights that you have got from the book and post it somewhere. It could be on Medium or any other blog. Just post it. Certainly, someone will find your work helpful and you can even get monetized!
The bottom line
Being more engaged and reinforcing the information regularly are great ways of remembering and retaining information. Combining them with sleep will certainly help you get more value from the stuff you read, however, using the tools without getting proper sleep is useless. Sleep is as important or even more important than the things you do while awake.
We all know someone from high school or college that didn't study that much neither put an all-nighter before an exam but always got higher grades than us. Maybe he was just getting enough sleep.