A producer for a television business show called and asked if I was available. He described the theme of the segment and asked if I had any ideas. I offered some possibilities.
“That sounds great,” he said. “We’re live in 30 minutes. And I need you to say exactly what you just said.”
“Ugh,” I thought. I’m not great at repeating exactly what I just said. So I started rehearsing.
Ten minutes later, he called to talk about a series he was developing. I almost asked him if we could postpone that conversation so I could use the time to keep rehearsing, but I figured since I had already run through what I would say two times, I would be fine.
Unfortunately, I was right. I was fine. Not outstanding. Not exceptional. Just … fine. My transitions were weak. My conclusion was more like a whimper than a mic drop. And I totally forgot one of the major points I wanted to make.
Which, according to Hermann Ebbinghaus, the pioneer of quantitative memory research, should have come as no surprise.
Ebbinghaus is best known for two major findings: the forgetting curve and the learning curve.
The forgetting curve describes how new information fades away. Once you’ve “learned” something new, the fastest drop occurs in just 20 minutes; after a day, the curve levels off.

Yep: Within minutes, nearly half of what you’ve “learned” has disappeared.
Or not.
According to Benedict Carey, author of How We Learn, what we learn doesn’t necessarily fade; it just becomes less accessible. In my case, I hadn’t forgotten a key point; otherwise I wouldn’t have realized, minutes after, that I left it out. I just didn’t access that information when I needed it.
Ebbinghaus would have agreed with Carey: He determined that even when we think we’ve forgotten something, some portion of what we learned is still filed away.
Which makes the process of relearning a lot more efficient.
Suppose that the poem is again learned by heart. It then becomes evident that, although to all appearances totally forgotten, it still in a certain sense exists and in a way to be effective. The second learning requires noticeably less time or a noticeably smaller number of repetitions than the first. It also requires less time or repetitions than would now be necessary to learn a similar poem of the same length.
That, in a nutshell, is the power of spaced repetition.

The premise is simple. Learn something new, and within a short period of time you’ll forget much of it. Repeat a learning session a day later, and you’ll remember more.
Repeat a session two days after that, and you’ll remember even more. The key is to steadily increase the time intervals between relearning sessions.
And — and this is important — to make your emotions work for you, not against you, forgive yourself for forgetting. To accept that forgetting — to accept that feeling like you aren’t making much progress — is actually a key to the process.
Why?
- Forgetting is an integral part of learning. Relearning reinforces earlier memories. Relearning creates different context and connections. According to Carey, “Some ‘breakdown’ must occur for us to strengthen learning when we revisit the material. Without a little forgetting, you get no benefit from further study. It is what allows learning to build, like an exercised muscle.”
- The process of retrieving a memory — especially when you fail — reinforces access. That’s why the best way to study isn’t to reread; the best way to study is to quiz yourself. If you test yourself and answer incorrectly, not only are you more likely to remember the right answer after you look it up, you’ll also remember that you didn’t remember. (Getting something wrong is a great way to remember it the next time, especially if you tend to be hard on yourself.)
- Forgetting, and therefore repeating information, makes your brain assign that information greater importance. Hey: Your brain isn’t stupid.
So what should I have done?
While I didn’t have days to prepare, still. I could have run through my remarks once, taken a five-minute break, and then done it again.
Even after five minutes, I would have forgotten some of what I planned to say. Forgetting and relearning would have reinforced my memory since, in effect, I would have quizzed myself.
Then I could have taken another five-minute break, repeated the process, and then reviewed my notes briefly before we went live.
And I should have asserted myself and asked the producer if we could talk about the series he was developing later.
Because where learning is concerned, time is everything. Not large blocks of time, though. Not hours-long study sessions. Not sitting for hours, endlessly reading and rereading or practicing and repracticing.
Nope: time to forget and then relearn. Time to lose, and then reinforce, access. Time to let memories and connections decay and become disorganized and then tidy them back up again. Because information is only power if it’s useful. And we can’t use what we don’t remember.
.
Critics:
Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some machines; there is also evidence for some kind of learning in certain plants. Some learning is immediate, induced by a single event (e.g. being burned by a hot stove), but much skill and knowledge accumulate from repeated experiences. The changes induced by learning often last a lifetime, and it is hard to distinguish learned material that seems to be “lost” from that which cannot be retrieved.
Human learning starts at birth (it might even start before) and continues until death as a consequence of ongoing interactions between people and their environment. The nature and processes involved in learning are studied in many fields, including educational psychology, neuropsychology, experimental psychology, and pedagogy. Research in such fields has led to the identification of various sorts of learning.
For example, learning may occur as a result of habituation, or classical conditioning, operant conditioning or as a result of more complex activities such as play, seen only in relatively intelligent animals. Learning may occur consciously or without conscious awareness. Learning that an aversive event can’t be avoided nor escaped may result in a condition called learned helplessness.
There is evidence for human behavioral learning prenatally, in which habituation has been observed as early as 32 weeks into gestation, indicating that the central nervous system is sufficiently developed and primed for learning and memory to occur very early on in development.
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