Forgetting Is a Feature, Not a Bug: How the Brain ‘Grasps’ New Concepts
The way teaching is typically done just doesn’t match how the brain actually learns.
“Our approach to teaching is based on the assumption that the teacher has a pen and the student's brain is a sheet of paper. That’s actually wrong,” says Sanjay Sarma, a professor and the vice president for open learning at MIT.
Instead, he likens good teaching to growing a plant. “We’re forming a model of the world, and the professor and everything else is in the service of that plant that is growing.”
Sarma just co-wrote a new book called “Grasp: The Science Transforming How We Learn.” It’s full of surprising truths about how the brain works when it comes to understanding new concepts.
Take how memory works, for instance. Forgetting is a key strength of the brain, even though it has to be fought against by teachers, he says.
“It's a very natural instinct to forget things,” says Sarma. “Forgetting is a very important step in the pathway to learning. And this might all seem very strange and mystical and mysterious, but it turns out this is a basic fact in neuroscience.”
That’s why professors need to space out lessons and reteach important material at intervals, he adds, to get past the tendency to forget.
Do you remember the temperature of the water when you washed your hands this morning, he asks? “You don’t because it’s useless information, unless it was an exception,” he says. “The reason the brain wants to forget stuff is most information is useless, but if it shows up two or three terms, the brain's like, ‘Oh my God, you know, I've got to remember this.’ So it is in fact, absolutely a feature, not a bug.”
Sarma is trained as a mechanical engineer, and he made a mark helping to develop RFID tags, sensors that are now common in retail and libraries to track items. And he says his research on the brain reminded him of what he knows about signal processing in electronics. “In signal processing, we call it a low pass filter,” he says, noting that things like a Zoom call continually edit out frequencies of sound that are considered noise and would interfere with hearing the voices of the participants.
Hear our conversation with Sarma on this week’s EdSurge Podcast. Find it on Apple Podcasts, Overcast, Spotify, Stitcher, Google Play Music, or wherever you listen to podcasts, or use the player on this page.