How We Learn: The Surprising Truth About When, Where, and Why It Happens

by Benedict Carey

Ballard doubted what he was seeing and ran hundreds of additional tests, with more than ten thousand subjects, over the next several years. The results were the same: Memory improved in the first few days without any further study, and only began to taper off after day four or so, on average. Ballard reported his findings in 1913, in a paper that seems to have caused mostly confusion. Few scientists appreciated what he’d done, and even today he is little more than a footnote in psychology, a far more obscure figure than Ebbinghaus. Still, Ballard knew what he had. “We not only tend to forget what we have once remembered,” he wrote, “but we also tend to remember what we have once forgotten.” Memory does not have just one tendency over time, toward decay. It has two. The other—“reminiscence,” Ballard called it—is a kind of growth, a bubbling up of facts or words that we don’t recall having learned in the first place. Both tendencies occur in the days after we’ve tried to memorize a poem or a list of words.