Study Mistake 5: Not reviewing material often enough

Why sleep, spacing and your subconscious are vital to your learning success

This is part 5 of the series: “The 6-Step Approach to Perfect Grades and Effective Learning”. Here’s part 4.

Photo by Aaron Burden on Unsplash

During high school and my first year of college, I had a magic number: 3 hours. None of my study sessions would be less than 3 hours, if at all possible. If I could study for longer, I would. A 6-hour marathon in the most quiet room I could find left me with an overwhelming sense of accomplishment. Deep in my bones was this delicious joy that was because I’d strongly moved the needle of my study goals. Oftentimes, when I had the opportunity for a 30 min study session, I would defer the studying until I had a large multi-hour window available on my calendar.

And then I realized that I was doing it completely wrong.

That was a blow to my self esteem. Most students fall into this same trap of believing that fewer and longer study sessions are more effective than multiple short study sessions. Others go one step further: they deliberately schedule the marathon study session just before the exam, incorrectly assuming the material will be “fresh” in their brains at exam time. Unfortunately, this thinking can seriously harm our studying effectiveness. Here are some common mistakes I’ve made and observed in other students:

1. Our study sessions are too long, and do not include appropriate rest.
2. We wait to study until just before the exam, believing that the closer to the exam we study, the “fresher” the material will be in our minds.
3. We don’t take enough breaks between consecutive study sessions.
4. We don’t account for the impact of sleep on our studying.

Let’s dive into each of these in a bit more detail.

Study breaks allow you to restore your focus

Imagine you’re at the gym lifting weights. You’re pushing your body to its limit. After a few repetitions, your muscles are burning, you’re fatigued and you know that trying to continue will not only be ineffective, it might actually injure you. Most people understand this intuitively, but don’t appreciate that studying works in somewhat similar ways.

And yet it is so. The muscles you “exercise” while studying are your attention and your focus. At the beginning of your study session: these are at 100%, and you’re completely in the zone. However, with each passing minute, you get slightly more fatigued, and it becomes more difficult to maintain your focus. As more time passes, you find yourself getting easily distracted, daydreaming, or checking TikTok. And worse, the amount of information you learn reduces sharply as you get more exhausted. Just like any muscle, your focus and attention need time to recover.

One solution to this focus-fatigue is to introduce short breaks into your study sessions. This is one of the central concepts of the Pomodoro technique. You set a timer (e.g. for 25 min), then study until the time ends with no interruptions, then take a 5 min break. After the break, continue studying for another 25 min, then take another break. After the 3rd study period, you take a longer break (e.g. to 20 min). The key is to break up a long study session to give your brain a few minutes to relax and refresh itself.

The key point here is to plan your day such that you study when your attention and focus are at their peak, and you’re mentally fresh. We each have different personal rhythms, so for you this might be first thing in the morning, or after a short nap, or after you’ve exercised. Find the times you’re mentally fresh and do everything you can to protect that time for your studying. And when you feel too tired while studying, take a break. There’s no point

Note that as you engage in more and more study sessions, you’ll get better at maintaining your attention and focus for longer periods. The focus “muscle” can be improved with practice and time.

Multiple sessions allow time to create structure

Ever felt great about the material you learned after an intense study session, only for the material to vanish from your memory within a week? That happens more often than you realize, and is related to how our brains learn and retain new information.

When you study material for the first time, your brain is busy trying to understand how everything fits together, and make sense of the overall structure of the information. This requires significant mental effort, so your brain is unlikely to capture all the tiny details of the material at the same time. In other words, you’ll likely miss a few concepts and details. And this is why you need a 2nd study session. You’ll notice details that you missed the first time. In addition, you’ll be more familiar with the material, and so you’ll be able to quickly focus on the areas that are still confusing. Taking it one step further, during the 3rd study session, you’ll have a chance to quiz yourself on both the high level structure of the material and the specific details. This allows you to focus on the few areas that still need clarification.

Every subject has a hierarchy of ideas. Some ideas are “building-block” concepts, because they’re the basic ideas upon which other ideas are built. You’ll need to understand these building blocks deeply before you can learn and appreciate higher level concepts. These higher level concepts are in turn the building blocks of even higher level concepts. Think of it like building a house: if you don’t have a strong foundation, you can’t build stable walls, and without solid walls, you can’t build a roof without the house collapsing.

Therefore, if the first time you’re reviewing material is just before the exam, you won’t have enough time to internalize higher level concepts, because you’ll be too busy familiarizing yourself with the building block concepts. Therefore you’ll go into the exam with only a weak understanding of higher level concepts, which isn’t a recipe for success.

Multiple sessions improve understanding

Sometimes, you’ll come across a concept that just doesn’t stick at the first time of asking. This is normal. We have different backgrounds, different experiences, different teachers, and varying ways of looking at the world. Textbook authors and YouTube creators don’t create content that is specifically customized to how you learn. So it’s perfectly ok to struggle from time to time. As we discussed in the article on testing your understanding, you might have to try several approaches before you have an “aha” moment and an idea clicks.

This is another reason why scheduling several study sessions is beneficial. If after the 1st study session, you’re still unclear about a concept, that should be an indication that you need to experiment with a different way of learning. A 2nd study session gives you the opportunity to test new approaches. And if that isn’t enough, you can always schedule a 3rd and a 4th session.

For example, if you read a textbook during your 1st review, try watching a video instead. If you watched a video, discuss the confusing concept with your classmate. Or find a website that explains the concept using diverse examples.

In short, interacting with the material frequently increases the chances you’ll retain more of it, and internalize it well enough to serve your purposes.

Spaced out study sessions improve memory

There are a number of reasons you should prefer scheduling different study sessions, with periods of rest and relaxation in between.

The Spacing Effect

There is strong research evidence that spacing out study sessions over longer periods improves long term memory. This is sometimes called the “spacing effect”, and has been replicated in several scenarios, including classrooms, quiz-taking students, and for learning languages. For example, if you have one week to study before an exam, and you can only spend 5 hours studying, would it be better to study for 1 hour per day for 5 days, or study in one 5-hour block? The spacing effect suggests you should choose five 1-hour study blocks.

The spacing effect explains why you should start studying as soon as possible. You’ll have more time to space out your studying, and increase the number of review sessions you can reasonably schedule, therefore maximizing the amount of material you retain.

Get lots of sleep

Another benefit of spacing out your study sessions is that you’ll get more sleep. There is a mountain of research evidence on the benefits of sleep for learning: it improves not only your memory, but also your ability to learn, to retain and recall information, and helps you solve problems more creatively.

In addition, research has shown that your brain consolidates and processes new information while you sleep. One of the most important times to sleep or take a nap is after a lesson or an intense study session. Not getting enough sleep deprives your brain of the opportunity to engage in these vital learning processes.

So next time you consider pulling an all-nighter or getting only 3 hours of sleep because you’re studying for an exam, I urge you to think again. You’re doing yourself more harm than good. Why not use sleep to your advantage?

Leverage your subconscious

Spacing out your study sessions allows your subconscious brain to process information in the background: dissect the new ideas, relate them to information you already know, and form new connections with other ideas. All this processing happens without you consciously thinking about it — so you’re essentially getting it for free!

Ever notice how solutions sometimes come to you while you’re in the shower, or just after you wake up from a nap, or when you’re out walking in nature? These are examples of your subconscious working through a problem, and then presenting the solution to your conscious brain, at which point you can access it.

So if you need yet another reason to space out your study sessions, this is it. Your subconscious brain will have more opportunities to help you untangle those difficult concepts you’ve been trying to understand.

Putting it all together

Interacting with your study material early and frequently gives you a huge advantage. Here are some of the principles for effective studying we’ve covered today:

1. Start studying as early as possible i.e. as soon as you get the material.
2. Start your study sessions when you’re mentally fresh and your attention and focus are at their peak.
3. Take sufficient breaks after every 20–40 minutes of studying. With more practice, your focus gets sharper, and you can study for longer before needing a break.
4. Space out your study sessions over several days. This makes the best use of your conscious and subconscious processing powers to learn and consolidate new ideas, relate them to ideas you already know, and effectively store them in long term memory.
5. Sleep is vital for your learning, so stop thinking of it as a waste of time, and realize it’s a super power that supports all your learning efforts.

If you liked this article, feel free to share with your friends, colleagues and fellow students who might find this beneficial.

Stay tuned for the last part of this series!