Want to recall 92% of everything you learn? This algorithm makes forgetting difficult

Want to recall 92% of everything you learn? This algorithm makes forgetting difficult

The Association for Psychological Science thinks it’s easily the best way to study. Lawyers are using it to pass the Bar. Harvard Medical School students are using it to become better doctors.

Is it a weird new tropical plant extract? A new pharmaceutical used by the rich and famous? Some kind of “limitless” pill you’d see advertised at the bottom of a dodgy website?

Actually, it’s a simple memory technique called SRS, or “Spaced Repetition System,” that anyone can use right from the comfort of their own home—completely legally!

The basics of Spaced Repetition

We all know that short-term memory is easy to develop. Just repeat something over and over, whether it’s a phone number or a list of verb conjugations, and you’ll remember it perfectly for a few minutes, hours, or if you’ve seen it before, possibly even a couple of days.

Transferring information into long-term memory is a bit more difficult. In the late 19th century, Hermann Ebbinghaus, a German researcher, measured how long it takes the average person to forget a list of random nonsense words. It turns out that over 90% of the information disappears within a few days. This is called the “forgetting curve.”

SRS forgetting curves

This curve (and not just post-exam festivities) is why we can remember pages upon pages of obscure facts right before we need them, and then remember almost nothing a few weeks later.

The best time to try to remember something is when it’s on the verge of being forgotten.

Fortunately, there is a way to reinforce the information so that the brain is less likely to forget it. The best way to improve recall, Ebbinghaus discovered, is to test the information frequently—but not too frequently. In fact, the best time to try to remember something is when it’s on the verge of being forgotten. That strengthens the neural pathways associated with the information, preserving it for a longer period of time.

Unlocking your supermemory

Of course, there is a point of maximum effectiveness. Review too often, and you’re wasting time. Review too seldom, and your memories begin to fade. There is a point of maximum efficiency for each individual, and it’s pretty darn difficult to pinpoint on your own.

Thankfully, computers can help us figure that out. If you have a list of things you want to remember—obscure medical terms, say, or Chinese characters—a computer can test you with them every so often to see how well the information is sticking. If you can’t remember it, the computer can shorten the repeat time. If you remember it well, the computer lengthens the time until the next review so that you’re always tested right as you’re about to forget for the greatest impact.

Coupled with creative use of the new information (working in a lab or hospital for medical students, having interesting conversations with locals for language learners), this method can be a powerful weapon in the learner’s arsenal.

Does SRS really work?

Over two dozen studies by Dr. Price Kerfoot, an Associate Professor of Surgery at Harvard Medical School, conclude that it does. Prof. Gabe Teninbaum, a Suffolk Law faculty member, agrees: “by using spaced repetition, users are projected to remember 92 percent of the material … and if that’s not enough, it ultimately takes less time to study and learn using spaced repetition than other study methods.”

“By using spaced repetition, users are projected to remember 92 percent of the material”

Oddly enough, learning actually seems to be increased during testing, where we’re forced to recall information ourselves, rather than studying, where we simply review or re-read the material. That’s part of why SRS is so effective. It forces our brains to make the connection and try to retrieve the information, rather than just reminding us about it over and over.

So why isn’t everybody doing it?

This system is a bit counterintuitive and does require making a commitment to review. Cribbing for an exam, on the other hand, gives you instant results and doesn’t require much set-up, even if you forget everything a few weeks later.

It may take a little more time to set up a system to practice Spaced Repetition, but it’s worth the wait. There are a few things you can do to make it more effective:

  • Break things up: If you need to learn something complex, like a language, break it up into bite-sized pieces that can be reviewed individually.
  • Make it a habit: If you’re in school or university, this is a bit easier. Just set aside a bit of study time each day to review flashcards or an ongoing list of material (you can add to it as time goes on).
  • Learn in context: Don’t study just words and characters—put them in context by using clear example sentences or other contextual aids.

Tools to get you started

There are a few ways to start reaping the benefits of spaced repetition, ranging from old school DIY methodologies to high-tech software based on latest breakthroughs in science.

Leitner flashcard spaced repetition system

If you printed out this article before reading, you’ll probably enjoy the Leitner system. Simply make five little boxes for your paper flashcards and move them to the next level each time you remember the answer correctly. If you fail, the flashcard goes back to the beginning. The higher the box number, the less frequently you should review the flashcards it contains.

For those of you who don’t mind integrating some technology into your studies, another easy-to-implement system is to schedule emails with material you want to learn every few days. If you use Gmail, Boomerang can help you do this quickly and easily.

For a truly high-tech approach, there are a number of excellent spaced repetition software packages including the original SuperMemo, open-source flashcard system Anki, and the multi-platform app Kleio. These applications work offline and offer a myriad of settings to play around with. Unfortunately, this flexibility comes at the cost of convenience, as they also require you to manually write your own flashcards or work with amateur shared decks that can be incomplete and prone to errors.

LinguaLift vocabulary learning app

We designed LinguaLift specifically for language self-learners with professionally curated, built-in sets of vocabulary on six different languages and writing lessons covering Japanese kanji, Chinese hanzi and Russian Cyrillic. When you need to review off-road, Fluent Panda is our upcoming mobile app which works offline and combines SRS with an adorable pet panda—possibly the cutest learning method of all time.

Ready to give it a go?

If you don’t want to risk money on unproven techniques, dodgy memory aids, or pseudo-illegal plant extracts—and you never want to have to cram for an exam again—give Spaced Repetition a try. You might just remember why you loved learning in the first place, and never forget anything ever again.