A memory might seem like a permanent, precious essence carved deep into the circuits of the brain. But it is not. Instead, scientists are discovering that a memory changes every time you think about it.
"Every time you recall a memory, it becomes sensitive to disruption. Often that is used to incorporate new information into it." That's the blunt assessment from one of the world's leading experts on memory, Dr. Eric Kandel from Columbia University.
And that means our memories are not abstract snapshots stored forever in a bulging file in our mind, but rather, they're a collection of brain cells — neurons that undergo chemical changes every time they're engaged.
So when we think about something from the past, the memory is called up like a computer file, reviewed and revised in subtle ways, and then sent back to the brain's archives, now modified slightly, updated, and changed.