The Science Behind Spaced Repetition

Have you ever spent hours staring at a textbook, feeling overwhelmed with the myriad of text and terms that you have to memorize for an exam? You memorize one term or date, but a few hours later you find yourself not being able to recall it. Even if you can recall it, 90% of new knowledge will be forgotten within three days if you don’t review it!?

Why does this happen? It is because what you memorized went into your short-term memory, and when you overwhelm yourself with too much information without revising the prior information, you don’t give your brain enough time to put anything into the long-term memory storage!?

This is a problem that has troubled humans ever since the beginning, and there have been many lying psychologists who have tried to figure out a way or hack to help us memorize countless information in a much shorter time. The psychologist who ended up figuring it out was the famous Herman Enbinghaus — with his finding of spaced repetition.?

Spacing Effect by Herman Enbinghaus in the late 19th century?

Ever heard of the “forgetting curve”? This is a curve that defines how long it takes for us to forget a new piece of information. Ebbinghaus discovered in 1885 that information retention decreases exponentially unless you review it periodically, and this curve illustrates how quickly we forget information if we don’t reinforce it!?

If you would like to read Ebbinghaus’ first published paper about the forgetting curve, it is called “Memory: A contribution to experimental psychology”.?

If you review the new information at specific time intervals, this can lead to longer retention… preventing the curve from curving down. This is called the spacing effect — your memory improves when you space out your study sessions over time rather than doing huge chunks of studying at the same time.?

Research has shown that if you repeat something 20 times over the course of one day (in other ways, cramming), it is less effective than if you repeat something 10 times over the span of a week!? This is because the human brain needs time to form new neural connections to remember new information. ??

To summarize: memory decays very fast in the early days and then more slowly as time passes, and the rate of decay or forgetting can be slowed down by repetition! ???

Mechanism behind spaced repetition?

“Cramming seeks to stamp things by intense application before the ordeal, but a thing thus learned can form few associations. On the other hand, the same thing recurring on different days, read, recited again and again gets well-wrought in our mental structure.” — William James, 1900.?

Consolidation and Reconsolidation: When we first learn a new piece of information, our brain works to “consolidate” or process this information. During this time, the brain is trying to store the information in our long-term memory.?

Over time, if we don’t review this information, we can forget it. This is prevented by “reconsolidation” during which we re-visit the information to reinforce and strengthen the memory. This reviewing process is crucial for the information to be stored in our long-term memory for long periods! ??

Optimal Retrieval Timing: ?Your review sessions should be done at a time in which you need to make an effort to remember the information, but it is not yet forgotten! The effort you put in to remember the information will help further strengthen your memory.?

This is why spaced repetition follows an algorithm of longer and longer periods between each review session as time passes. The interval between study sessions gradually increases as you strengthen your memory. ???

Active recall: this is a much more effective way of studying than passively reading a textbook or listening to a lecture! Active recall forces you to recollect information from memory, which alone helps reinforce neural pathways to help you better remember the information in the future. ?????

Personalized studying: the intervals between review sessions is based on your own performance. After you attempt to recall a piece of information, you have to rate your confidence on a scale. Based on this scale, the algorithm will calculate how much time should pass til you have to revise the information again.?

This is important because it allows you to focus your study sessions on areas where you are the weakest while skipping things that you know perfectly.

Scientific evidence ???

Many studies have shown that people who study with spaced repetition perform better on exams than those who cram or study for a shorter period. Cramming might feel productive, but spaced repetition is a scientifically proven method that ends up helping you be more productive and effective in the long run ????.

One notable study is an experimental psychology study which found that people who used spaced repetition to study had an average recall accuracy of 80%, which is significantly higher than that 60% in the group that crammed everything! The below infographic dives into further notable studies and reviews.?

Onto more productive study sessions!?

To memorize huge amounts of information, you don’t need to cram hours and hours every day. To be honest, doing this might make you exhausted and forget everything during the exam! Instead, you can try spaced repetition with apps like Voovo to put all the information in your long-term memory! This way, you can go to your next exam with full confidence. ??

Remember, the brain is phenomenal but it still needs time to be able to absorb new information, process it, and consolidate it. By studying through spaced repetition, you give your brain enough time to do all of this and store the newly learned information in your long-term memory! ??

Ready to bring the power of spaced repetition to your classroom?

Explore how Voovo for Classroom can help you create engaging, effective learning experiences that enhance long-term retention for your students.