Most of us think of forgetting as the brain letting us down. You walk into a room and can't remember why, or a name you know perfectly well refuses to show up. But what if some forgetting isn't a mistake at all?
Here's the surprising part: researchers have shown that people can forget on purpose, at least partly. In lab experiments, when people are told to forget certain words, they later recall those words much less well than words they were told to remember. The brain also seems able to block unwanted memories from coming to mind, a skill psychologists call retrieval suppression.
Forgetting on Instruction
One way scientists study this is called directed forgetting, an idea first developed by psychologist Robert Bjork. Volunteers see a list of words, and after each one they're told either to remember it or forget it. Later, they're surprised with a test of all the words. Recall for the to-be-forgotten words is often much worse.
In one study, people kept a diary of two events from each day for five days, then were told to either remember or forget them. After another five days of diary entries, they were asked to recall everything. The people told to forget had worse recall for the first week than the second.
Interestingly, the memories don't seem to be erased. One leading explanation is that the instruction to forget makes them harder to retrieve, while they can still be recognized if they're shown again.
Remembering Can Make You Forget
Here's another odd twist. Practicing some memories can make related ones fade. Psychologists call it retrieval-induced forgetting. If you study a list of words by category and then practice recalling only some of the words in one category, the unpracticed words in that same category become harder to remember later.
In everyday life, this may help the brain keep the information you actually use front and center, instead of letting every similar memory compete for attention.
Forgetting Has Always Followed a Pattern
Some of the earliest research on forgetting came from German psychologist Hermann Ebbinghaus in 1885. Using himself as the only test subject, he memorized lists of nonsense syllables and measured how quickly he lost them. He found that much of what we forget slips away soon after we learn it, and then the forgetting levels off. His methods were simple, but later and more careful studies have backed up his basic findings.
Rehearsal is the antidote. Studies show that going over information again improves how well it sticks, because rehearsal helps move it into long-term memory.
When Forgetting Doesn't Come Easily
People who struggle to forget show why forgetting matters. The famous Russian memory performer Solomon Shereshevsky could recall decades-old experiences in fine detail. His abilities caused confusion in his mind, and he reportedly wrote things on paper and burned them in an attempt to forget them. Later in life, he reportedly found he could forget facts simply by wanting to, though this was never directly tested.
Jill Price, the first documented case of a condition called hyperthymesia, can apparently recall nearly every day of her life from age 14. She has described how one memory triggers another and how she feels powerless to stop it.
So the next time something slips your mind, try not to be too hard on yourself. A little forgetting is part of how a healthy brain clears space for what matters most. If memory changes ever worry you, talk to your doctor.
