Spaced repetition in learning theory

Spaced repetition in learning theory

December 3, 2019 47 By Stanley Isaacs


Like most students, you’ve probably crammed
the night before an exam. And after it, you probably did OK or maybe
you even did well, but did you remember any of what you learned after the exam? One evidence-based way to better remember
what you’ve learned is through Spaced Repetition, or spacing out your learning and practice
of new knowledge or skills. Although this might seem novel, this is hardly
a new concept; it was first described in 1885 by a German psychologist named Herman Ebbinghaus. Here’s how it works. Say you plot your retention, or how much you
remember of something, vs. time. Now you learn that something on day 0. Without reviewing it, the “forgetting curve”
will look like an exponentially decaying curve, which is kind of scary! If you review (or better yet actively retrieve)
the material at increasingly spaced intervals after learning it, then the forgetting curve
starts to flatten out and you’ll get a lot better longer-term retention. Now, the goal here is to review the material
at the right time. It turns out that the best time to revisit
information that you are trying to learn is right around the time you would naturally
forget it. Since forgetting typically follows this exponential
curve, the trick becomes timing your study sessions around it. Practically, this means having more widely
spaced intervals between study times for the material that you are more familiar with,
and shorter intervals between study sessions for material that you are less familiar with. While this strategy would be effective for
all fields of study, it is especially important for students in the medical field, who have
to retain key knowledge and skills in order to care for their patients. Kind of frighteningly, one study found that
without spaced repetition, after one year medical students forgot up to 33% of their
basic science knowledge, and after two years, more than 50%! But when students and residents applied spaced
repetition strategies in their studying, they significantly outperform their counterparts,
with some studies showing close to 40% greater learning efficiency. Knowing about spaced-repetition is one thing,
but what about applying it? Students—especially those in the health
and medical fields—have to remember hundreds or even thousands of “bits” of knowledge
and skills. Because of this, it would be incredibly hard
for them to keep track of when they should revisit each piece of information—especially
since each bit of information will follow its own learning curve. This is why researchers and software developers
are using computer algorithms to try to help students optimize their studying. These algorithms help you learn by sorting
information based on your responses to questions—so if you get a question wrong, they will automatically
prioritize that information for repetition over the information in questions you answered
correctly. In doing this, these algorithms can actually
reduce your overall study time by making sure the time you are spending studying for your
exams isn’t wasted on studying information that you can already reliably recall. One of the best parts of spaced repetition
is that it suggests that we can gain a lot by studying smarter, not necessarily longer. With just a little more organization or forethought
on your part, you can achieve a whole lot more. That said, spaced repetition means challenging
yourself to apply your learning right at the point where you’re starting to forget it,
and that can sometimes be kind of hard! So, just know that if a spaced repetition
regimen feels difficult, even frustrating, that can mean that it’s doing exactly what
it’s supposed to be doing. Okay one final point. In some fields (like health and medicine)
certain knowledge may change relatively quickly because of new discoveries, so it’s important
to know the right new information, rather than remembering the wrong old information
for a long time. That’s why you should make sure that the
tools you use to do the spacing are also designed to help you stay current. Alright time
to get studying.