I went to medical school when I was 18 and since then I have studied easily over 10,000 hours yes that is a lot of studying and the majority of that time was spent on revision and review I used everything from space repetition and active recall with flash cards to practice questions summary Pages brain dumps but I finally discovered one of the most powerful techniques of all and it's called interleaving in this video I'm going to tell you exactly how you can use interleaving to upgrade your revision and become a more efficient learner by the way when I say the word revision I'm talking about going over material and reviewing stuff that you've already studied before I know some other countries use different words I'll start off by telling you what interleaving is and how to do it and at the end of the video I'll give you my four rules that you can follow to make sure you're doing into leaving the right way if you're new to the channel welcome I'm DrJustin s I'm a full-time learning coach and the head of learning at iin study I'm also a former medical doctor and I've worked with tens of thousands of students from around the world to help them learn more efficiently now imagine if there was a single technique that was so effective Ive that it could help you improve your memory improve your test performance even help you to learn new Concepts that you have never encountered before well that is what interleaving is so let me explain how it works back in high school I used to be really involved in techwondo it was actually like the first sport that I was ever really good at very stereotypical Korean I know but we used to do these drills where we kick the paddle you know someone's holding a pad and you aim for it and then you kick it and instead of just practicing kicking the same paddle how at the same distance the same every single time what we' do is sometimes we' Bring It Forward sometimes we' bring it closer and so we would have to adjust on the Fly where to aim our kick and by doing this it would train my ability to use that kick in any situation the reason I'm telling you this is because that is actually a form of interleaving and the concept is very similar for studying interleaving is when you learn something by mixing different concepts and different facts different angles and variations while you learn something instead of of doing what's called blocked practice which is where you would just start with one concept and you learn it fully before moving on to the next one blocked practice for practicing a kick would be holding it in the exact same place every single time until I've mastered it and then moving it higher moving it lower forward back for something like basketball it would be standing on the free throw line practicing shooting it from that exact same spot every single time until you've mastered it but with interleaving that's when we are changing things up we're moving it Forward we're moving it back we're standing in front of the line we're standing a little bit behind the line left of the line right of the line and we're giving ourselves variations of the same concept and so for studying it's about looking at a concept from multiple different perspectives to help understand it rather than trying to understand it through just one perspective first for example let's say that I'm learning about the effect of British colonialism on India the blocked method of learning which by the way is the most common way that people use would be to learn about each Effect one by one an inter leave method would be to take all of the different effects try and generally understand one of them then move on to another effect and compare and contrast them to find similarities and differences and then we do the same thing for another effect and we look for similarities and differences and then after we've done three different effects we might move back to the first one and learn that one a little bit more deeply and then again compare and contrast that with the second one and the third one and that cycle continues until we have learned everything if I'm learning something more technical like the physiology of how a muscle contracts a blocked method would be to learn the physiology and just learn that process until I feel like I've completely understood it and then maybe a week later during a revision session I'm going to test myself with some practice questions and flash cards in that method we're looking at one concept from one perspective until we feel like we're fully mastered it using inter leaving would mean that I learn how the muscle contracts in a normal situation and then I compare that with how it is in a disease situation and then maybe how I would treat that diseased muscle later when I go to test myself and review it I'm going to be focusing on comparing and contrasting the differences between those situations see now it's the same process but we're looking at that process from multiple angles the process of normal versus disease versus treating that disease and trying to get it back to normal and that comparing and contrasting is where the value seems to be into leaving as helpful because by giving yourself very variations of a concept it helps your brain form a better picture of what the concept is versus what it is not it pushes your brain to pay attention to the parts of the information that make it characteristic and sticky I sort of think of it like trying to understand what a place looks like by looking at a photo of it for a really long time versus being able to visit the actual place and explore and look around seeing something from multiple angles helps you understand each of those angles much more easily and more quickly and more memorably and speaking of which if you found that this is an angle on learning that you found helpful then I'd appreciate if you give this video a like every like helps with the algorithm which helps me make more content for free now this inter leave method is really different to how I used to study when I was in my early years of uni I used to have these really big revision days where I'd sit down once a week for like 6 or 7 hours and try to get through as much of one paper as possible and is to create these huge huge summary pages and brain dumps on like the whole week or fortn night's worth of lectures and the end of the session I'd have this beautiful summary page like perfectly you know all the headings and completely organized and the nice tables and everything sometimes I'd even print them out and like create my own little like mini textbook but fast forward a few weeks and I'm looking at these Pages wondering where all the knowledge went and even though I knew I had a good basic understanding of all the facts I had good fact recall I was confident in that knowledge I knew knew that when I walked into the exam there would still be some questions that I'm going to get wrong that I cannot answer there's an angle that I have not considered and I have not looked at and I don't know what it is but it's like a fact of the universe there's going to be something that I get wrong now the reason interleaving is relevant here is because interleaving actually directly helps to protect you against those tricky curveball questions by helping you see more of those angles that you otherwise may have missed and it isn't incredibly effective there's a lot of ongoing research on interleaving researchers still don't exactly know what inter leing is and exactly how it works based on the pace of the research it's probably going to be at least another 10 years before we know that a recent systematic review and met analysis on inter leaving found a Hedges G value of effect size at 0. 65 for memory improvement and transfer transfer is what we call your ability to take what you've already learned and use that to learn new things that you haven't encountered before and a value of 0. 65 is considered moderately strong and you might be thinking moderately strong doesn't sound that impressive but you would be wrong learning is really complicated and there are a lot of things that influence your learning there are very very few techniques where a single technique is able to have that level of impact for reference some Studies have found that just writing notes the general idea of writing notes only has an effect size of around 0.
5 and simply rereading and rewriting notes has an effect size of around 0. 2 to 0. 3 even spacing combined with free active recoil which is where you review something and then you wait a little while and then you review it again from memory which is considered one of the most effective strategies that's ever been found it is like the only strategy that people swear by on YouTube and it is the underlying concept that basically all flashcard apps are built around has an effect size hovering at around 0.
