Forgetting Isn't Always Bad — It Helps Us Make Better Decisions

Forgetting isn't always a brain malfunction, new research shows. In fact, it's an important part of memory processing. Sadeugra/E+/Getty Images
Forgetting isn't always a brain malfunction, new research shows. In fact, it's an important part of memory processing. Sadeugra/E+/Getty Images

From flashcards and textbooks to puzzles and online brain twisters, countless adults spend years info-cramming. There are approximately 100 billion neurons (which are integral to the memory storage process) in the human brain, so there's a lot of room for that information. And science has placed much value on people's ability to remember more info for long periods. But according to a new research review published in the journal Neuron, we may be better off if we just forget some memories, instead.

University of Toronto neuroscientists Blake Richards and Paul Frankland, co-authors of the paper, suggest that good memory does not equate to remembering many accurate details over time, a concept known as persistence. Actually, they propose, our brains are working to forget memories, in order to encourage intelligent decision-making. The goal of memory is to hold on to valuable information, not just that which is accurate, they say in the research. This way, we can draw from useful, significant memories to make real-world decisions.

"If you're trying to navigate the world and your brain is constantly bringing up multiple conflicting memories," says Richards in a press release, "that makes it harder for you to make an informed decision."

Lending credence to their argument, the researchers found that forgetting, or transience, plays an important role in the brain that's separate from memory storage. Synaptic connections between neurons are purposefully weakened or tossed. And as new neurons flood the brain's hippocampus to encode and store memories, they overwrite existing connections, which can become more difficult to access.

The researchers even looked into mechanisms associated with artificial intelligence to understand memory loss better. They concluded that forgetting obsolete or distracting information promotes decision-making by allowing the brain to generalize past events to create new ones, a principle called regularization in AI. Breaking memories down into simpler forms without unnecessary and outdated details, like a summary, makes them more effective in current situations. We are able to make informed choices in new situations because we only apply important, broad recollections, rather than specific ones.

Think of it this way: Forgetting irrelevant details is like packing only important items when moving and leaving behind all the random knickknacks, to create room for more valuable belongings.

The team suggests that the degree of memory persistence and transience varies depending on environment, and the interaction between the two is key. For instance, a banker who sees many new people may remember customer names for short periods, while financial planners will remember names longer since they see clients more regularly. However, don't point to this research if you forget your anniversary or other significant events constantly. Psychologically, natural forgetting is a gradual process and shouldn't be equated with serious memory loss, such as dementia.

But when it comes to the small stuff, don't sweat it — forget it.