It sounds completely counter-intuitive. But forgetting is actually helpful for memory and for general cognitive processing. In fact, once we forget something and then have to retackle the subject again, our understanding becomes better than ever.
A full report of this phenomenon was covered in a recent story by Ulrich Boser in the New York Times. I thought it was fascinating and am now experimenting with revisiting some things I’d studied once and forgotten (like re-reading an old textbook or sight-reading a piano piece I knew in high school).
Here’s an excerpt of the Times story:
Forgetting is supposed to be the antithesis of learning, and whether we’re a kid or an adult, most of us are plainly embarrassed if we can’t recall a name or fact. But it turns out that forgetting can help us gain expertise, and when we relearn something we couldn’t recall, we often develop a richer form of understanding.
The notion that forgetting is a hidden educational virtue goes back a century or more. In a series of studies, the German psychologist Hermann Ebbinghaus found that when people relearn information, they’re more likely to recall that information in the future.
Research explains why forgetting delivers this memory boost. Memories don’t fly out of our brains like sparrows from a barn. Instead, our brain will make memories more or less accessible. Some recollections, like the name of a close friend, are easily recalled. Other details, like the color of your childhood bedroom, have been tucked into deep storage and are much harder — if not impossible — to retrieve.
In this sense, a forgotten memory is a lot like an old file on your computer. While the document still exists, you don’t have a good way of getting to it, and today many memory researchers don’t even use the word “forgetting.” The term implies that a recollection is gone forever. Instead, forgetting is a matter of “retrieval failure.”
Besides the occasional memory gaffe, the brain’s approach to forgetting serves us well, and our retrieval failures help prune away memories that we don’t really need. Or consider living with an unending library of easily recalled memories. It would be overwhelming: Dates, names, phone numbers — they would all be constantly top of mind.
In this model of forgetting, when we extract a detail from the brain’s long-term storage, that detail becomes easier to recall in the future.
So if you want to recall where you parked the car today, then practice remembering that specific location. If you want to easily summon the names of state capitals, then make sure to draw regularly on the names of state capitals.
Our brain is built to foster this sort of forgetting and remembering, according to a paper released in June in the journal Neuron. In the article, the researchers argue that many of the brain cells associated withmemory actively foster memory loss. “The growth of new neurons seems to promote forgetting,” the researcher Blake Richards said. “If you add new neurons, it effectively overwrites memories and erases them.”
The benefits of forgetting go far beyond facts or even brain cells, and when we relearn something that we’ve forgotten, we often gain deeper forms of insight.
Studies show that forgetting can even promote better reasoning. In a study released in 2011, a group of psychologists gave some subjects a problem-solving exam. Known as the Remote Associates Test, it requires a subject to read three words (like “playing,” “credit” and “report”) and then come up with a word that would link all three ideas (“card”).
The researchers added a wrinkle to the test, and they provided the subjects with some “misleading” training, giving the subjects the wrong cues before they took the exam. The results showed that people had to push the misleading association out of their minds to solve the problem. “Creative cognition,” the authors wrote, “may rely not only on one’s ability to remember but also on one’s ability to forget.”
Benjamin Storm, a psychologist at the University of California, Santa Cruz, led the 2011 study, and he now takes the idea of forgetting pretty seriously. If Professor Storm writes a paper, he’ll start it early so that he has time to revisit his writing. Similarly, he will read important articles twice with a long break in between so that he gains more from the text.
A lack of remembering comes with plenty of downsides. Forgetting can have uncomfortable consequences. After Justin Bieber blanked out on the words to his Latin pop hit “Despacito” in May, the backlash was fierce, and TMZ ran the headline “Justin Bieber, No Hablo Espanol.”
What’s more, people can’t leave too much time in between recalling something or they’ll have a hard time pulling that detail from memory. This explains why parents and teachers are right to worry about summer learning loss after all. If a student has not recalled a math fact for months, it will be hard to recall that fact come September.
Still, forgetting can be a crucial driver of learning. Expertise is what fills our memory gaps. A learning loss can be a learning gain. In his song “Sorry,” Mr. Bieber crooned that he wanted “one more shot at second chances.” At least when it comes to learning and forgetting, he’s right.
You can read the full story here: