In the quest to fend off forgetfulness, some people build a palace of memory.
It’s a method for memorizing invented in ancient times by (legend has it) the Greek poet Simonides of Ceos, more recently made popular by multiple best-selling books (and the “mind palace” of Benedict Cumberbatch’s Sherlock Holmes).
Memory palaces provide imaginary architectural repositories for storing and retrieving anything you would like to remember. Sixteen centuries ago, St. Augustine spoke of “treasures of innumerable images” stored in his “spacious palaces of memory.” But 21st-century scientists who study memory have identified an important point to remember: Even the most luxurious palace of memory needs trash cans.
“There are memories that we don’t want and we don’t need,” says the neuroscientist Maria Wimber, of the University of Birmingham in England. “Forgetting is good, and an adaptive thing.”
Traditionally, forgetting has been regarded as a passive decay over time of the information recorded and stored in the brain. But while some memories may simply fade away like ink on paper exposed to sunlight, recent research suggests that forgetting is often more intentional, with erasure orchestrated by elaborate cellular and molecular mechanisms. And forgetfulness is not necessarily a sign of a faulty memory. “In fact,” Wimber says, “it’s been shown over and over in computational models and also in animal work that an intelligent memory system needs forgetting.”
Far from signifying failure, forgetting may be the brain’s frontline strategy in processing incoming information. Forgetting is essential, some researchers now argue, because the biological goal of the brain’s memory apparatus is not preserving information, but rather helping the brain make sound decisions. Understanding how the brain forgets may offer clues to enhancing mental performance in healthy brains while also providing insights into the mechanisms underlying a variety of mental disorders.