Charan Ranganath is a professor of neuroscience and psychology and director of the memory and plasticity program at the University of California, Davis. He has been studying the neuroscience of memory for more than 25 years.
Below, Ranganath shares five key insights from his new book, Why We Remember: Unlocking Memory’s Power to Hold on to What Matters. Listen to the audio version—read by Ranganath himself—in the Next Big Idea app.
1. Memory is not about the past; it’s about the present and future.
Whenever I tell people that I study memory, one of the most common responses I get is, “Maybe you can study me—my memory is terrible.” And sure, I get it, whether it’s being unable to recall someone’s name, trying to find where you put your keys, or even losing track of what you were talking about a few minutes ago, forgetting sucks. But let’s face it: We all forget, and if there is one thing that memory research has shown, it is that most of our experiences are doomed to be forgotten. And that’s okay because our most typical complaints and worries about everyday forgetting are driven mainly by deeply rooted misconceptions about what memory is for in the first place.
Contrary to popular belief, the neural mechanisms of memory were not cobbled together to remember the name of the guy we met at that thing. Memory is the process by which our brains extract what’s important—that is, information that helps us make sense of an uncertain and ever-changing world. We use memory to reason, plan, and imagine, to communicate and connect, to forge our identities, and to ground ourselves in time and space.
When we look at memory as a resource to pull from, as opposed to a comprehensive archive of the past, we can make mindful choices in the present to curate a rich set of memories to take with us into the future.
2. Memories are dynamic.
When we recall a memory, we don’t replay the past; we imagine how the past could have been. This means that our recollections are shaped by our beliefs, goals, and perspectives, much like a painting reflects an artist’s unique perspective on their subject. Whenever we reconstruct these memories, the brain tinkers with them, strengthening, weakening, or modifying different aspects of the memory from the moment it is pulled up. The constructive and malleable nature of memory means that we can often remember events incorrectly, sometimes leading to colossal errors, such as when news anchor Brian Williams mistakenly recalled being in a helicopter that was shot down in Iraq.
Our brains are susceptible to distorted memories by design. The world around us is constantly changing, so we need to update our memories to reflect these changes. If you catch someone you thought was trustworthy in a lie or got food poisoning after a tasty dinner at a new sushi restaurant, you’d want to adjust your recollections based on that new information.