The next time your brain refuses to recall a simple fact or name, be thankful. That’s because according to University of Toronto professors Blake Richards and Paul Frankland, could be a sign that your brain is getting rid of unnecessary information so that it can operate more efficiently, and help you make better decisions.
The researchers say there are numerous neurobiological studies conducted on how the brain stores information, a process called persistence. However, it is only lately that scientists have begun paying attention to forgetting, or transience. That’s because like us all, scientists also assumed that our occasional inability to recall facts was due to a failure mechanism in the brain.
In 2013, Frankland and his team discovered that as new neurons integrate with the hippocampus — a region of the brain that plays a significant role in learning and remembering – they overwrite old memories, making them harder to access. There is also evidence that the brain deliberately weakens or eliminates synaptic connections between neurons, in which memories are encoded.
Richards and Frankland, who published their findings in the journal Neuron in April 2017, have a theory on why the brain spends so much energy erasing memories. They believe forgetting old information makes the brain more efficient. For evidence, they cite a 2016 study where an independent team of scientists taught a group of mice to locate a maze. The researchers then erased the memories of a subset of the rodents with drugs and moved the maze. The mice who still had memories of its original location had a harder time finding the new site than those that had no recollection.
Additionally, the team believes that retaining too much detail could prevent us from making good decisions. Richards, who studies the parallels between artificial intelligence (AI) and neuroscience, likens this behavior to a phenomenon called regularization in the AI world. This is where a machine is trained to forget the little details to understand the bigger picture. For example, if you teach a computer to recognize faces by memorizing each one, it will be unable to identify a new face. That’s because instead of recognizing that faces are generally oval, have two eyes, one nose, and a mouth, the computer learns the particulars of distinct faces – things like the color of eyes or shape of lips.
“We all admire the person who can smash Trivial Pursuit or win at Jeopardy, but the fact is that evolution shaped our memory not to win a trivia game, but to make intelligent decisions," says Richards. "And when you look at what's needed to make intelligent decisions, we would argue that it's healthy to forget some things."
The scientists say what the brain decides to forget is determined by our daily life. An example Richards gives is that of our brains dispensing the need to remember phone numbers. He says "Instead of storing this irrelevant information that our phones can store for us, our brains are freed up to store the memories that actually do matter for us."
In fact, the researcher encourages people to help their brains declutter by exercising regularly, stating, “We know that exercise increases the number of neurons in the hippocampus.” While that may cause you to lose some memories, Richards believes, “They're exactly those details from your life that don't actually matter, and that may be keeping you from making good decisions."
So the next time you are unable to recall a seemingly important fact, don’t be hard on yourself. Just chalk it down to your brain “spring cleaning” to make room for information that can contribute to making you smarter! Remember, even Albert Einstein was absent-minded!
Resources: cnn.com, utoronto.ca, the verge.com