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How We Learn Summary

14 min read ⌚ 

Quick Summary: How We Learn by Benedict Carey uses the newest findings related to the nature and biology of our brains as a springboard for a fun-to-read exploration of our learning habits and a sort of operational manual on how to tweak them so that you can harness the full power of your innate memory mechanisms.

How We Learn Summary

Who Should Read “How We Learn”? And Why?

How We Learn is one of those books – akin to Daniel Kahneman’s Thinking, Fast and Slow or Charles Duhigg’s The Power of Habitwhich discover and explain things you’ve certainly felt before, but couldn’t really understand the mechanism.

And these books are great because once you understand how something works, it’s fairly easy to use it to your benefit.

Now, look back at the title of the book.

That’s right: this is the book which can help you get better grades!

Did we pique your curiosity?

How We Learn Summary

Part One: Basic Theory

1. The Story Maker: The Biology of Memory

“The science of learning is, at bottom,” writes Benedict Carey, “a study of the mental muscle doing the work – the living brain – and how it manages the streaming sights, sounds, and scents of daily life.”

“That it does so at all,” he adds, “is miracle enough. That it does so routinely is beyond extraordinary.”

So, what will you be able to see if you’re allowed a peek behind the curtains? Who are the protagonists, what are the relations between them, what helps them do a better job and what doesn’t?

Unsurprisingly, the guys we’re interested in when studying memory are the 100 billion neurons which make up the grey matter of your brain.

Now, these guys are stimulated constantly. Memories are nothing more but patterns of stimulations.

To understand this better, say that you have merely 10 neurons. If an event stimulates three of them in the order 1–5–8, these three neurons would form a pattern, a network of neurons which are called synapses.

Each time you’d try to recall that memory, these synapses will be stimulated yet again; that way, they grow thicker; and the thicker they are – the more you remember something.

There’s a twist, though.

Most of the conscious here-and-now memories are stored by the neurons located in the hippocampus; however, after a while, if they are important enough, they are transferred to the neocortex.

That’s why people whose hippocampus is destroyed are still able to remember old stuff, though unable to create new memories.

2. The Power of Forgetting: A New Theory of Learning

We’ve already introduced you to guys such as Kevin Horsley, an International Grandmaster of Memory and two-time Memory World Record holder, and Joshua Foer, the 2006 US Memory Champion.

There’s an interesting thing science has discovered – and Benedict Carey wants you to know about them: the ‘losers’ in these memory competitions stumble not because they remember too little, but because they remember too much.

In other words, they are, in a way, much more incapable of forgetting the wrong things remembering the right ones.

What does that say about how we learn?

Well, writes Carey, “if recollecting is just that – a re-collection of perceptions, facts, and ideas scattered in intertwining neural networks in the dark storm of the brain – then forgetting acts to block the background noise, the static, so that the right signals stand out. The sharpness of the one depends on the strength of the other.”

In other words, remembering, counterintuitively, doesn’t work without forgetting.

Contrary to what your textbooks would have you believe, it’s much easier to remember things than forget them.

The problem is your brain stores all kind of information, and the trick is how to teach it to store the right information, the one you’re actually interested in.

“Using memory changes memory,” writes Carey, “and for the better. Forgetting enables and deepens learning, by filtering out distracting information and by allowing some breakdown that, after reuse, drives retrieval and storage strength higher than they were originally.”

“Those are the basic principles that emerge from brain biology and cognitive science,” he concludes, “and they underlie – and will help us understand – the various learning techniques yet to come.”

Part Two: Retention

3. Breaking Good Habits: The Effect of Context on Learning

You’ve probably heard this quite a few times, but it’s worth pointing it out again: the surroundings during a study session affect your ability to remember things.

Possibly the most famous proof of this is the opening scene in Marcel Proust’s In Search of the Lost Time when the main protagonist suddenly remembers the all-but-forgotten early days of his life after tasting a madeleine, the cookie which on Sunday mornings his aunt gave him when he was merely a child.

And a study by a psychologist named Steven M. Smith has proved this.

In 1985, Smith had a group of 54 Psych 101 students study a list of 40 words. The students were divided into three groups: one group studied in silence, another group was listening to Milt Jackson’s ‘People Make the World Go Around,’ and a third one studied to Mozart.

The students spent ten minutes memorizing the words and two days later were asked to retrieve them without a prior warning.

You guess what happened!

If one studied to Mozart and was asked to recall words while Mozart was once again playing in the background – he did twice as good as one who studied to Mozart and was asked to recall words in silence or to the tune of “People Make the World Go Around.”

Apparently, the music didn’t matter: the same equation held true for the ones who studied while listening to Milt Jackson. But silence did: the ones who studied in silence remembered twice less than the others, regardless of which environment they were asked to remember the words.

However, what this research shows is not that we need to learn with music – but that we need to change the context if we want to remember the thing itself without outer cues.

4. Spacing Out: The Advantage of Breaking Up Study Time

Has your mother ever told you something along the lines of “Honey, don’t you think it would be better to study for a little bit tonight and a little bit tomorrow, rather than trying to learn everything at once?”

Well, if she has – then (surprise! surprise!), she was right, and you (chances are) were wrong not to heed to her advice.

The technique your mother suggested is called, scientifically, distributed learning or, more commonly, the spacing effect.

It means that people learn at least as much – and retain it a lot longer – when they distribute (or “space”) their study time as opposed to concentrating it.

In layman’s terms: cramming the night before the exam will probably help you pass the exam as much as spacing out the study material over the week. However, by the time the second semester comes, you’ll probably remember nothing.

“In terms of reliability,” Carey uses a nice analogy, “nocturnal sprint is a little like overstuffing a cheap suitcase: the contents hold for a while, then everything falls out.”

The lesson?

If you want to pass the exam, it doesn’t make any difference whether you’ll cram or space out; however, if you really want to learn and remember something than cramming is the very, very wrong way to go.

It will get you a degree, sure – but not knowledge.

5. The Hidden Value of Ignorance: The Many Dimensions of Testing

Have you ever found yourself in a situation such as this?

You’ve just finished reading an interesting book, and your colleagues start a conversation related to the topic this book examines.

You feel confident to interrupt them: “But no – that’s not the way things are.”

And then you start explaining the things you’ve just learned and, even though at home you felt like you’ve understood everything, suddenly you are unable to clarify even the basic premises.

Stage fright?

Could be – but it is not.

What it is – a misjudgment of the depth of your knowledge.

In other words, you had the right neurons fired up while reading, you did; but the synapses you just formed were too weak and gangling to help you remember the things afterward.

The solution?

If you want to remember something well, try explaining it to someone else, even if that someone is, well, you.

Test your knowledge in the silence of your room in any way possible – because that’s not actually testing, but learning.

And it is not just regular studying – it is studying “the high-octane kind, 20 to 30 percent more powerful than if you continued sitting on your butt, staring at that outline. Better yet, those exercises will dispel the fluency illusion. They’ll expose what you don’t know, where you’re confused, what you’ve forgotten—and fast. That’s ignorance of the best kind.”

Part Three: Problem Solving

6. The Upside of Distraction: The Role of Incubation in Problem Solving

True, we live in a distraction-full world and, as you probably already know, distractions are not helpful if you want to do some deep work.

Interestingly enough, they seem to be a shortcut to a better problem-solving ability.

Yup, we’re talking about the nature of the Eureka factor yet again.

We still don’t know why – but studies have confirmed it over and over again – taking a break from a project helps you finish that project not merely more successfully but also more efficiently.

For one reason or another, a period of incubation (a period during which you’re not thinking about a project) makes you more capable of solving problems.

A decade ago, a pair of psychologists at Lancaster University in the United Kingdom – Ut Na Sio and Thomas C. Ormerod – tried to understand this phenomenon better and their final results are as thus.

First of all, they concluded that the incubation effect is real. However – and secondly – it doesn’t always work as expected, because of the circumstances and the distractions included.

Sio and Ormerod divided incubation breaks into three categories:

Relaxing (like listening to music);
Mildly active (like surfing the Internet);
Highly engaging (like writing a short essay).

Well, it seems that as far as math or spatial problems are concerned, you can benefit from either of these three. However, in the case of linguistic problems (such as anagrams), only the second category actually helps.

Also, incubation periods seem to work better if they are longer – i.e., about 20 minutes – and don’t do the job if they are short (i.e., 5 minutes).

The most important thing?

“People don’t benefit from an incubation break unless they have reached an impasse.” Or, in layman’s terms: “Knock off and play a videogame too soon and you get nothing.”

7. Quitting Before You’re Ahead: The Accumulating Gifts of Percolation

We guess percolation is not a word you’ve heard before – not unless you’ve read this book.

Because it is a word Carey introduces to describe something usually mixed up with incubation – namely, to describe longer-term, cumulative thinking processes similar to incubation.

“To solve messier, protracted problems,” writes Carey, “we need more than a fast-acting dose, a short break here and there. We need an extended-release pill.”

If you are an artist or a poet, you probably already know what we’re talking about.

“I have to be alone,” explained once Joseph Heller, “A bus is good. Or walking the dog. Brushing my teeth was marvelous – it was especially so for Catch-22. Often when I am very tired, just before going to bed, while washing my face and brushing my teeth, my mind gets very clear… and produces a line for the next day’s work or some idea way ahead. I don’t get my best ideas while actually writing.”

This may have to do a lot with something called the Zeigarnik effect after Russian psychologist Bluma Zeigarnik.

She was a student of Gestalt psychologist Kurt Lewin who once noticed that a waiter remembers better the unpaid orders than the paid ones.

After she did a couple of experiments, she realized that this is a natural bias: we tend to remember better things that are not finished than finished ones.


Because finishing them is akin to crossing out something on your checklist: a cue for your brain to stop thinking about it anymore.

The reverse is true as well: constantly starting something “often gives that job the psychological weight of a goal, even if it’s meaningless.”

Consequently, interruption pushes the thing you’re interrupting to the top of your mental to-do list.

And that’s percolation at its best!

8. Being Mixed Up: Interleaving as an Aid to Comprehension

Have you ever heard the phrase: “it’s not an adventure until something goes wrong”?

If so, you already know that it comes from the world of climbers and hikers, where wrong means wrong wrong: “a rope snaps; the food supply flies overboard; a bear crawls into the tent.”

And you know what happens next: suddenly climbers and hikers start to think more clearly and understand things they wouldn’t otherwise.


Well, because we’re creatures of habit and we tend to adapt to just about everything. While that is good for your body and your brain in terms of conserving energy for later, it is not good for your learning capabilities.

Because adapting to something puts your brain on autopilot; and you don’t want your brain to be on autopilot if you really want to comprehend something.

The solution?


Interleaving is a cognitive science word, but it simply means “mixing related but distinct material during study.”

Basically, it is the reason why your music teacher switches from scales to theory, to pieces all in one sitting; it’s not a bad idea – but, actually, the best one.

Interleaving is “essentially, about preparing the brain for the unexpected,” a “way of building into our daily practice not only a dose of review but also an element of surprise.”

It is – to use an analogy – a sort of an alarm, a reminder, a cue to signal your brain that it shouldn’t be on autopilot.

Part Four: Tapping the Subconscious

9. Learning Without Thinking: Harnessing Perceptual Discrimination

Perceptual discrimination is the reason why Tom Brady is such a great QB.

Namely, he’s not able to see more than the other QBs in a shorter time; quite the opposite: he’s able to see less, aka discern the right things in an instant.

When you’re in the pocket, there are so many things happening around you that it is fairly difficult to realize what’s happening even as an outsider watching it on TV.

The moment you find out what has actually happened is the slo-mo replay.

Well, in a way, Brady sees it in slow motion throughout: that’s why, for many sports players, the phrase “the game has slowed down for me” is practically synonymous with “now, I make better decisions.”

The mechanism underlying this is perceptual discrimination: the ability to see only what it matters. And if there’s such thing as perceptual seeing, there’s also a thing such as perceptual learning.

According to Eleanor Gibson, a pioneer in the field, perceptual learning has three traits:

• It is not a passive absorption, but an active process, “in the sense that exploring and searching for perception itself is active.” In other words, “we do not just see, we look; we do not just hear, we listen.”
• It is also self-regulated, “in the sense that modification occurs without the necessity of external reinforcement;”
• Finally, it is stimulus-oriented, “with the goal of extracting and reducing the information simulation.”

To sum up, “the system works to find the most critical perceptual signatures and filter out the rest.” Tom Brady doesn’t need to see everything: he just needs to see the movements of the people who might stop him.

He filters out the rest.

And “discovery of distinctive features and structure in the world is fundamental in the achievement of this goal.”

10. You Snooze, You Win: The Consolidating Role of Sleep

“If only I could sleep less than three hours – I would have learned much more!”

Now, how many times have you said that before an important exam?

If you’re like most of the students – probably at least three or four times a year. Which is exactly the number of times you were wrong about it!

We don’t know a lot about sleeping, but we do know this: it is so intricately related to memory, that it is virtually impossible to consolidate new memories if you remain awake for longer periods of time.

However, as you know full well, there are different phases of sleep, and some of them are more important to certain types of activities than others; even more importantly, sleeping during different periods of the day makes a difference as well.

For example, if you are interested in retaining facts and learning vocabulary words, then it’s best to go to bed early in the night; however, if you are a creative person, then you better become a night owl: creative thinking requires REM sleep, and this happens mostly in the morning hours.

Now that you know this, it’s time to start a sleep revolution in your life; which is essentially the same as a studying revolution.

“I no longer think of naps or knocking off early as evidence of laziness, or a waste of time, or, worst of all, a failure of will,” concludes Carey. “I think of sleep as learning with my eyes closed.”

Key Lessons from “How We Learn”

1.      Remembering Is Not the Opposite of Forgetting – But Its Corollary
2.      Incubation, Percolation, and Interleaving: Three Concepts to Know If You Want to Solve Problems
3.      Change the Studying Context and Test Yourself to Remember Better

Remembering Is Not the Opposite of Forgetting – But Its Corollary

We learn and remember things by creating networks of neurons called synapses; the thicker these synapses are, the more long-term the memory and the easier to recall it.

However, if you want to remember specific things, then the trick is to forget everything else

Forgetting acts as a sort of a background noise blocker, a static, which makes the right signal stand out.

As Carey says, the sharper your forgetting, the stronger your memory.

Incubation, Percolation, and Interleaving: Three Concepts to Know If You Want to Solve Problems

Incubation, percolation and interleaving are three interrelated concepts which can help you solve problems better.

Incubation is basically another word for the Eureka effect: we tend to see old problems better after a 20-minute break.

Percolation is the same, but over a longer period: if you want to write a better novel, then interrupt writing it daily with a long walk or something like it; this will stimulate to think of better ideas.

Finally, interleaving means mixing things up: don’t learn just theory and then practice, but learn a chunk of theory, then practice it, then another chunk of it.

Change the Context and Test Yourself to Remember Better

If you sometimes forget somebody’s name, go to the place where you met the person, and there’s a good chance that you’ll remember it.

The other side of this coin: if you really want to remember things regardless of the context, then study them in different situations and circumstances, so that they don’t get too attached to a certain set of conditions.

Also, once you do learn them, test your knowledge by transforming your mental knowledge into a speech.

That is the only way for you to realize whether you know them fluently.

Like this summary? We’d like to invite you to download our free 12 min app for more amazing summaries and audiobooks.

How We Learn Quotes

Once a goal becomes activated, it trumps all others and begins to drive our perceptions, our thoughts, our attitudes. Click To Tweet Some of what we’ve been taught to think of as our worst enemies – laziness, ignorance, distraction – can also work in our favor. Click To Tweet Sticking to one learning ritual… slows us down. Click To Tweet Memories evaporate entirely from the brain over time if they’re not used. Click To Tweet The collective findings of modern learning science provide much more than a recipe for how to learn more efficiently. They describe a way of life. Click To Tweet

Final Notes

How We Learn – to quote a review by Scientific American – “is more than a new approach to learning; it is a guide to making the most out of life. Who wouldn’t be interested in that?”

That’s a rhetorical question for a reason!

Revelatory and unputdownable, How We Learn is not merely a psychological study into the inner workings of a brain, but a set of hacks which can help you learn and remember better.

In other words, it is both an entertaining and a valuable tool for everybody.

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