Speaker 1: It's always important to make sure you are not wasting time and effort on inefficient study, and while techniques like flashcards or actively engaged with the material are super helpful, they are hard to get used to. Many people don't try these out in the first place because such methods seem too intimidating and hard to implement. But there is one simple technique which would boost the effectiveness of your studying immensely in absolutely no time. Stay tuned for that. My name is Artem. I'm a computational neuroscience student and researcher. On this channel, we explore mental and digital tools to help us study and learn more effectively. Today, I'll talk about interleaving, a very simple trick which would let you double or even triple the effectiveness of your study time. So, what is interleaving? Whenever you are learning something, be it a motor practice, like throwing different types of baseball pitches, a math skill, memorizing skull bones, or learning to classify paintings and artists, you can practice it either in a blocked fashion, A-A-A-B-B-B-C-C-C, where each letter indicates a different type of abstract task, like throwing a curveball versus a slider, or applying integration by parts versus a change of variables, or you can shuffle the items and do what's called the interleaved practice, A-B-A-C-C-A-B-C-A-C. It has been shown experimentally many times that introducing such interleaved practice to pretty much learning any skill improves the consequent performance, i.e. makes the learning more effective. And since I always try to understand deeper the underlying cause of everything, the question arises, why the heck does changing the order of items being practiced make such a huge difference? And there is a caveat, which becomes apparent if you are familiar with spaced repetition. Memories decay over time, and you need to refresh them every once in a while to stay sharp. This is what spaced repetition technique is based upon. You basically space out learning something in time so that the memory about it doesn't decay. It always jumps back, and you get a better retention. Now look at what happens when we shuffle the items. All three of those inevitably get spaced out in time. And so the question arises, could it be that the main benefit of interleaving is not in the shuffling per se, but rather this spacing in time? So what do we do to find out? Fix the amount of spacing in both blocked and interleaved practices and compare the performance. By designing an experiment to control for this spacing effect, researchers have found that interleaving per se indeed does cause the increased performance. So it's a whole separate thing of its own. But the question remains, what's so special about altering the order? Interleaving teaches you when to use a particular method, not just how to use it, since for every problem you need to choose the appropriate strategy to solve it, not just blindly apply the one that authors of the textbook have spoon-fed you by grouping the problems under a corresponding heading. It's a very important skill, which mimics the real world in a way, because when you solve problems, in reality, you're not provided with explicit strategy on how to solve it. You need to choose it yourself or even create one from scratch, and it's an incredibly valuable skill of its own. As a classical example, consider the problem. A bug flies five miles to the east and then three miles to the north. How far from his starting point is he now? If this problem was located under the Pythagorean theorem heading in the book, you would already know what to do with the numbers and just blindly apply the formula. It takes away a very important aspect, visualizing the problem, figuring out its main gist, what strategies could be used, what is it about, the feeling of the problem. It's sort of a meta-solving, because normally you allow the problem to dissolve into your cortex. But in the case like this, authors take away this huge part of the problem. They provide a shortcut, give hints, which makes the problem much more easy and is harmful in the long run. Of course, this is a toy example, but such blocked practice is ubiquitous in mathematics textbooks. It's a tragedy, because most of the time, choosing the right strategy is the hardest and most important part. Imagine you're practicing testing the convergence of two equations. Well, then, of course, you know what to do with it. Or better yet, if it happens in the statistics textbook, with different statistical tests, where choosing the right test is the real problem. Remember the example of learning the styles of different painters, and how they used different colors to paint their paintings? Interestingly, interleaving improved the performance on novel examples that the subject has never seen before. This indicates that it's not just mere memorization going on, and nor there are any explicit strategies or techniques you need to learn. When you are saying, well, this one's Van Gogh, and this one's, I don't know, Goya, or this one's, I don't know, Van Gogh, and this one's Van Gogh, you're not really learning the styles of the painters, When you are saying, well, this one's Van Gogh, and this one's, I don't know, Goya, something just clicks in your head and you know the answer. The same happens when you are learning to classify dog breeds or bird species. Interleaving improves the performance there as well. There is probably some internal mechanism, which allows you to build abstract representations and to better find hidden differences between them. When two examples are compared side by side, interleaved with each other, not when similar examples are batched together. I guess it could be compared to the experiment. When you have two colors side by side, it's very easy to say which one is darker, even if they differ only slightly in contrast. If you are shown the same colors in sequence, here's the first one, and here's the second. Can you tell which one is which? See, because they are kind of spaced out, you don't see them side by side. It's really hard to find this difference. Maybe it's like an extreme example of bringing two items closer, the similar thing that happens during the interleaved practice. If I just say interleave stuff, you're gonna kill me, aren't you? Well, it really depends on your workflow, your setup, your teacher, the types of problems you want to practice, etc. Most of the time, it's pretty intuitive and self-explanatory how to implement this interleaved practice into your work. Just always keep this effect in mind. For example, if you are using flashcards, either paper ones or software like Anki, well, first of all, good for you. Their interleaving is inevitable, because, you know, you shuffle the deck. Like I said, this effect is really clear in mathematics and other subjects like physics, computer science, economics, basically anywhere where you have to solve problems. If you have to do a bunch of exercises that are grouped by section, one thing you could do is take photos or screenshots of all of them so that each image has only the text of the problem itself. Then jumble all the pictures into one folder and pick at random images from there. The number of files should ideally be equal to the number of problems so that you will make sure no two exercises came from the same section. I mean, at least you won't know that. That's pretty much it. If you like the video, subscribe to the channel, share it with your friends, press the like button and stay tuned for more interesting stuff coming up. Goodbye and thanks for the interesting knowledge.