Spaced Repetition: what is it and why is it so effective?

The spaced repetition system or spaced repetition algorithm is a vocabulary learning technique that helps you memorize new words and phrases for the long-term. As you progress from review to review, the time intervals between reviews increase until you can effortlessly recall the word even after a long break. For example, you practice the word now, then in an hour, then in 1 day, 2 days, 4 days, etc. until it's in your long-term memory. The interval increases only if you are able to recall the word correctly.

The forgetting curve

Memory research has proven that we tend to forget newly acquired information very quickly unless we reinforce this information. In fact, we tend to forget 50% of the new information within days after learning it. The concept of forgetting curve demonstrates how we lose new knowledge. Anytime you learn something new, your goal should be to flatten the forgetting curve, that is to extend the time the information fades away. The best way to achieve that is via active recall.

What is active recall?

Spaced Repetition ensures active recall. Compared to matching meanings as in multiple choice quizzes, active recall is the process of retrieving information from your memory.

Let me illustrate this. Imagine you want to stop by a bakery in Berlin and want to buy a loaf of bread. Before you even approach the shop, you try to remember how to say bread in German. Das Brot – a lightbulb goes off in your head. This is an example of an active recall. You essentially pulled the word out of your memory

Alternatively, if you approached the shop and saw a sign saying das Brot, this would count as a passive recall. You saw the word and then matched it to its meaning.

Passive recall is much easier and creates a false sense of progress. However, recognizing a word when you see it doesn't mean it is in your active memory and that you are able to quickly remember it in real-life situations, such as a conversation with a colleague. That's why multiple-choice matching games in some language learning apps are fun but often ineffective.

That's why HeyLama's vocabulary feature uses Spaced Repetition and active recall to help you effectively memorize new vocabulary that you discover during lessons or on your own. It's fun and effective at the same time.

Learn more about Spaced Repetition

1. Wikipedia article
2. Intro to Spaced Repetition for vocabulary learning – YouTube video by 5-minute language
3. Here is another video primer from a memory improvement YouTube channel.