According to the Bjorks’ theory, storage strength can increase but it never decreases. This does not mean that everything we see, hear, or say is stored forever, until we die. More than 99 percent of experience is fleeting, here and gone. The brain holds on to only what’s relevant, useful, or interesting—or may be so in the future. It does mean that everything we have deliberately committed to memory—the multiplication table, a childhood phone number, the combination to our first locker—is all there, and for good.
