Tag: Memory

The Spacing Effect: How to Improve Learning and Maximize Retention

We are not taught how to learn in school, we are taught how to pass tests. The spacing effect is a far more effective way to learn and retain information that works with our brain instead of against it. Find out how to use it here.


— Gerald Edelman, Second Nature: Brain Science and Human Knowledge

The most important metaskill you can learn is how to learn. Learning allows you to adapt. As Darwin hinted, it’s not the strongest who survives. It’s the one who easily adapts to a changing environment. Learning how to learn is a part of a “work smarter, not harder” approach to life—one that probabilistically helps you avoid becoming irrelevant. Your time is precious, and you don’t want to waste it on something which will just be forgotten.

During the school years, most of us got used to spending hours at a time memorizing facts, equations, the names of the elements, French verbs, dates of key historical events. We found ourselves frantically cramming the night before a test. We probably read through our notes over and over, a gallon of coffee in hand, in the hope that the information would somehow lodge in our brains. Once the test was over, we doubtless forgot everything straight away.1

Even outside of formal education, we have to learn large amounts of new information on a regular basis: foreign languages, technical terms, sale scripts, speeches, the names of coworkers. Learning through rote memorization is tedious and—more important—ineffective. If we want to remember something, we need to work with our brains, not against them. To do that, we need to understand cognitive constraints and find intelligent ways to get around them or use them to our advantage.

This is where the spacing effect comes in. It’s a wildly useful phenomenon: we are better able to recall information and concepts if we learn them in multiple, spread-out sessions. We can leverage this effect by using spaced repetition to slowly learn almost anything.

It works for words, numbers, images, and skills. It works for anyone of any age, from babies to elderly people. It works for animals, even species as simple as sea slugs. The effect cuts across disciplines and can be used to learn anything from artistic styles to mathematical equations.

Spaced repetition might not have the immediacy of cramming or the adrenaline rush of a manic all-nighter. But the information we learn from it can last a lifetime and tends to be effectively retained. In some ways, the spacing effect is a cognitive limitation, yet a useful one—if we are aware of it.

In Fluent Forever: How to Learn Any Language and Never Forget It, Gabriel Wyner writes:


In Mindhacker, Ron and Marty Hale-Evans explore further:



— Edgar Allan Poe, Marginalia

The Discovery of The Spacing Effect

Hermann Ebbinghaus (1850-1909), a German psychologist and pioneer of quantitative memory research, first identified the spacing effect. After earning his PhD in Germany, he traveled to London. Like so many people, he found his life forever changed by a book.

The work in question was Elements of Psychophysics by the pioneering experimental psychologist Gustav Fechner. Inspired by this book, Ebbinghaus began the research into memory that would consume his career and impact all of us.

Ebbinghaus took up his new field of study with the unbridled zest of a newcomer. He didn’t believe strongly in the prevailing understanding of memory at the time. In his wish to avoid getting bogged down in theory, he made everything about experimentation. As researcher and the sole subject of his experiments, he faced an uphill battle.

His most important findings were in the areas of forgetting and learning curves. These are graphical representations of the process of learning and forgetting. The forgetting curve shows how a memory of new information decays in the brain,2 with the fastest drop occurring after 20 minutes and the curve leveling off after a day.

There is a way to slow down the process of forgetting. We need only to recall or revisit the information after we originally come across it. Going over the information later, at intervals, helps us remember a greater percentage of the material. Persistence will allow us to recall with 100% accuracy all that we want to remember.

The learning curve is the inverse. It illustrates the rate at which we learn new information. When we use spaced repetition, the forgetting curve changes:

Frequency matters. Under normal conditions, frequent repetitions aid memory. We know this intuitively. Just try to memorize this article on a single repetition. However much attention, focus, or individual ability you have, it won’t work.

Memory mastery comes from repeated exposure to the material. Ebbinghaus observes, “Left to itself every mental content gradually loses its capacity for being revived, or at least suffers loss in this regard under the influence of time.” Cramming is not an effective memorization strategy. Lacking the robustness developed in later sessions, crammed facts soon vanish. Even something as important and frequently used as language can decay if not put into use.

There are other ways to improve memory. Intensity of emotion matters, as does the intensity of attention. Ebbinghaus notes in his definitive work on the subject, Memory and Forgetting:


Ebbinghaus also uncovered something extraordinary: even when we appear to have forgotten information, a certain quantity is stored in our subconscious minds. He referred to these memories as savings. While they cannot be consciously retrieved, they speed up the process of relearning the same information later on.


As the first researcher to undertake serious experimentation on memory and why we forget, Ebbinghaus transformed psychology as a new branch of science. His impact has been compared to that of Aristotle. Ongoing research into the spacing effect continues to support Ebbinghaus’s findings.

“There is no such thing as memorizing. We can think, we can repeat, we can recall and we can imagine, but we aren’t built to memorize. Rather our brains are designed to think and automatically hold onto what’s important. While running away from our friendly neighborhood tiger, we don’t think “You need to remember this! Tigers are bad! Don’t forget! They’re bad!” We simply run away, and our brain remembers for us.”

— Gabriel Wyner, Fluent Forever: How to Learn Any Language and Never Forget It

How the Spacing Effect Works

Let’s take a quick refresher on what we know about how memory in works, because it’s not what we think.

Memories are not located in any one part of the brain. Memories are formed in a process which involves the entire brain. If you think about your favorite book, different parts of your brain will have encoded the look of it, the storyline, the emotions it made you feel, the smell of the pages, and so on. Memories are constructed from disparate components which create a logical whole. As you think about that book, a web of neural patterns pieces together a previously encoded image. Our brains are not like computers – we can’t just ‘tell’ ourselves to remember something.

In Mastery, Robert Greene explains:

In the end, an entire network of neurons is developed to remember this single task, which accounts for the fact we can still ride a bicycle years after we first learned how to do so. If we were to take a look at the frontal cortex of those who have mastered something through repetition, it would be remarkable still and inactive as they performed the skill. All their brain activity is occurring in areas that are lower down and required much less conscious control…People who do not practice and learn new skills can never gain a proper sense of proportion or self-criticism. They think they can achieve anything without effort and have little contact with reality. Trying something over and over again grounds you in reality, making you deeply aware of your inadequacies and of what you can accomplish with more work and effort.

No definitive answer has been found to explain how the spacing effect works. However, a number of factors are believed to help:

Forgetting and learning are, in a counterintuitive twist, linked. When we review close to the point of nearly forgetting, our brains reinforce the memory as well as add new details. This is one reason practice papers and teaching other people are the most effective ways for students to revise—they highlight what has been forgotten.

Retrieving memories changes the way they are later encoded. In essence, the harder something is to remember now, the better we will recall it in the future. The more we strain, which is painful mental labor, the easier it will be in the future. There is no learning without pain. Recall is more important than recognition. This explains why practice tests are a better way to learn than opening your text and re-reading your highlights.

Our brains assign greater importance to repeated information. This makes sense; information we encounter on a regular basis does tend to be more important than that which we only come across once. Disregarding any forms of mental impairment, we don’t have trouble recalling the information we need on a daily basis. Our PIN, our own telephone number, the directions to work, and names of coworkers, for example. We might once have struggled to remember them, but after accessing those sorts of information hundreds or thousands of time, recall becomes effortless.

Some researchers also believe that semantic priming is a factor. This refers to the associations we form between words which make them easier to recall. So, the sentence ‘the doctor and the nurse walked through the hospital’ is easier to remember than ‘the doctor and the artist walked through the supermarket’ because the words ‘doctor’ ‘nurse’ and ‘hospital’ are linked. If you are asked to remember a logical sentence such as ‘mitochondria is the powerhouse of the cell’, it’s not too difficult. If those same words are scrambled and become ‘cell the house mitochondria power is of’ it’s a lot harder to remember. And if those words are broken up into nonsensical syllables – ‘th ell ce he ous hon mit odria fi of’ – retaining them would become arduous. But some researchers have theorised that repetition over time primes us to connect information. So, if you revised ‘th ell ce he ous hon mit odria fi of’ enough times, you would start to connect ‘th’ and ‘ell.’ We can demonstrate semantic priming by telling a friend to say ‘silk’ ten times, then asking them what a cow drinks. They will almost certainly say ‘milk.’ The answer is, of course, water.

Yet another theory is that of deficient processing. Some literature points to the possibility that spaced repetition is not in itself especially efficient, but that massed learning is just very inefficient. By comparison, spaced repetition seems special when it is, in fact, a reflection of our true capabilities. Researchers posit that massed learning is redundant because we lose interest as we study information and retain less and less over time. Closely spaced repetition sessions leverage our initial interest before our focus wanes.

With properly spaced repetition, you increase the intervals of time between learning attempts. Each learning attempt reinforces the neural connections. For example, we learn a list better if we repeatedly study it over a period of time than if we tackle it in one single burst. We’re actually more efficient this way. Spaced sessions allow us to invest less total time to memorize than one single session, whereas we might get bored while going over the same material again and again in a single session. Of course, when we’re bored we pay less and less attention.3

In Focused Determination, the authors explain why variety also contributes to deficient processing.

There is also minimal variation in the way the material is presented to the brain when it is repeatedly visited over a short time. This tends to decrease our learning. In contrast, when repetition learning takes place over a longer period, it is more likely that the materials are presented differently. We have to retrieve the previously learned information from memory and hence reinforce it. All of this leads us to become more interested in the content and therefore more receptive to learning it.

“How do you remember better? Repeated exposure to information in specifically timed intervals provides the most powerful way to fix memory into the brain. …Deliberately re-expose yourself to the information more elaborately, and in fixed, spaced intervals, if you want the retrieval to be the most vivid it can be. Learning occurs best when new information is incorporated gradually into the memory store rather than when it is jammed in all at once.”

— John Medina, Brain Rules

Taking Advantage of the Spacing Effect

We don’t learn about spaced repetition in school—something which baffles many researchers. Most classes teach a single topic per session, then don’t repeat it until the test.

Going over a topic once teaches very little—sometimes nothing at all, if the teacher is unengaging or the class is too long. Most teachers expect their students to take care of the memorizing part themselves. As a result, many of us develop bad learning habits like cramming to cope with the demands of our classes.

We need to break up with cramming and focus on what actually works: spaced repetition.

The difficulty of spaced repetition is not effort but that it requires forward planning and a small investment of time to set up a system. But in the long run, it saves us time as we retain information and spend less total time learning.

A typical spaced repetition system includes these key components:

  • A schedule for review of information. Typical systems involve going over information after an hour, then a day, then every other day, then weekly, then fortnightly, then monthly, then every six months, then yearly. Guess correctly and the information moves to the next level and is reviewed less often. Guess incorrectly and it moves down a level and is reviewed more often.
  • A means of storing and organizing information. Flashcards or spaced repetition software (such as Anki and SuperMemo) are the most common options. Software has the obvious advantage of requiring little effort to maintain, and of having an inbuilt repetition schedule. Anecdotal evidence suggests that writing information out on flashcards contributes to the learning process.
  • A metric for tracking progress. Spaced repetition systems work best if they include built-in positive reinforcement. This is why learning programs like Duolingo and Memrise incorporate a points system, daily goals, leaderboards and so on. Tracking progress gives us a sense of progression and improvement.
  • A set duration for review sessions. If we practice for too long, our attention wanes and we retain decreasing amounts of information. Likewise, a session needs to be long enough to ensure focused immersion. A typical recommendation is no more than 30 minutes, with a break before any other review sessions.

The spacing effect is a perfect example of how much more effective we can be if we understand how our minds work, and use them in an optimal way. All you need to learn something for life are flashcards and a schedule. Then, of course, you’re free to move on to actually applying and using what you’ve learned.


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  • 1

    When is the last time you used a2+ b2= c2 in real life?

  • 2

    This is different than the half-life of knowledge, the process by which information in memory becomes less valuable because your understanding of the world has changed.

  • 3

    You can test this by asking yourself what your last meeting yesterday was about.

Let Go of Self-Justification

Our desire to justify our actions and believe we’ve always done the right thing can lead us to distort our view of reality. We prefer preserving our self-image to seeing the truth. Here’s how to let go of self-justification.


It can be startling and unsettling to confront how bad humans are at describing reality with any objective accuracy. Because of the way our brains work, how perceptions are distorted, the ambiguity of language, we seem forever destined to never really know this world we are living in. What are we to do?

One answer is to accept that there is no one objective truth so stop searching for it. Instead, we can put our efforts into understanding ourselves a little better, allowing for navigation between the many truths that exist for people, to achieve success.

In Mistakes Were Made (But Not by Me)Carol Tavris and Elliot Aronson explore the role of self-justification in our creation of reality. We make assertions about the world as if they are facts while being completely blind to the subjectivity inherent in knowing anything. Essentially we create a narrative about the world that reflects our beliefs about the kind of person we are and assign to this narrative a ‘truth’ which does not, in fact, exist.

What is self-justification?

It is not the same thing as lying or making excuses. … [It] is more powerful and more dangerous than the explicit lie. It allows people to convince themselves that what they did was the best thing they could have done. In fact, come to think of it, it was the right thing.

Self-justification is a portrayal of the brain that, despite its stated goals or desires, is not interested in truth, but rather self-preservation. Admitting you were wrong may save relationships and lives, it may prevent distress and war, but it will also force you to admit that the narrative you have constructed about yourself is wrong. And depending on how committed you are to that narrative, you may be unable to even see that you made a mistake, let alone confront it.

Self-justification has costs and benefits. By itself, it’s not necessarily a bad thing. It lets us sleep at night. Without it, we would prolong the awful pangs of embarrassment. We would torture ourselves with regret over the road not taken or over how badly we navigated the road we did take. … Yet mindless self-justification, like quicksand, can draw us deeper into disaster. It blocks our ability to even see our errors, let alone correct them. It distorts reality, keeping us from getting all the information we need and assessing issues clearly. It prolongs and widens rifts between lovers, friends, and nations. It keeps us from letting go of unhealthy habits. It permits the guilty to avoid taking responsibility for their deeds. And it keeps many professionals from changing outdated attitudes and procedures that can harm the public.

The book contains many unsettling examples from politics and law enforcement. Research based stories of officials who refused to admit their mistakes even when confronted with irrefutable evidence they were wrong. The more invested you are in a situation, the more extensive your narrative, the more likely that narrative has become intertwined with your self-worth and self-esteem, and therefore the harder to rewrite it in light of your errors.

Perhaps the most startling examples of the descent into irreversible self-justification is the research conducted on what the authors call ‘the closed loop of clinical judgment’. They discuss the total lack of evidence to support the theory that traumatic events are suppressed by the brain and contrast this with the amount of clinical practitioners who will enter into therapeutic relationships with the pre-supposition that the client’s current troubles are being caused by traumatic events that they don’t remember.

It becomes a no-win situation for the person seeking therapy – either they spontaneously remember past trauma (which, actually, is the one thing they were not likely to forget in the first place) or they say that they have no memory of being traumatized (in which case the therapist assumes the memories are still being repressed). Either outcome reinforces the self-justified narrative that the therapist has created.

As evidence accumulated on the fallibility of memory and the many confabulations of recovered-memory cases the promoters of this notion did not admit error; they simply changed their view of the mechanism by which traumatic memories are allegedly lost. It’s not repression at work anymore, but dissociation; the mind somehow splits off the traumatic memory and banishes it to the suburbs. This shift allowed them to keep testifying, without batting an eye or ruffling a feather, as scientific experts in cases of recovered memories.

This speaks to investment in the narrative. This is not about admitting that yelling at your spouse about forgetting to buy ice cream was a mistaken over-reaction. In the case of these practitioners, this is their career. It is also the many lives they may have destroyed by unintentionally encouraging false memories of trauma. It would not be easy for any of us to admit mistakes when the consequences of those mistakes are so devastating.

How can we remember things that didn’t happen? Because self-justification has an effect on our memories.

Between the conscious lie to fool others and unconscious self-justification to fool ourselves, there’s a fascinating gray area patrolled by an unreliable, self-serving historian – memory. Memories are often pruned and shaped with an ego-enhancing bias that blurs the edges of past events, softens culpability, and distorts what really happened.

We remember our past in a way that confirms what we believe of ourselves in the present.

When we do misremember, our mistakes aren’t random. The everyday, dissonance-reducing distortions of memory help us make sense of the world and our place in it, protecting our decisions and beliefs. The distortion is even more powerful when it is motivated by the need to keep our self-concept consistent.

The authors present many fascinating examples of totally fabricated ‘memories’. Not ones that are intentional, but situations in which the memories were believed to be genuine and turned out to be false. In all cases the memories had been unconsciously altered or created to support a self-justifying narrative. For example, believing you are an independent free-spirit, you remember your actions as always having been so, or conversely you remember the past as more awful than it was in order to support your narrative of strength and change.

If a memory is a central part of your identity, a self-serving distortion is even more likely.” How many of us have come across our old journals or diaries, and felt like they were reading the life story of someone else? We will frequently look at the entries and say ‘wow, I don’t remember being like this at all’.

Okay, so our memories are unreliable. Hardly a surprise. For the millions of people who frantically search for their car keys every morning, it will not be shocking that your fourth year birthday cake wasn’t the bad-ass Batman you remember, but a cute puppy with giant eyes. So why worry about memory?

The self-justifying mechanisms of memory would be just another charming and often exasperating aspect of human nature were it not for the fact that we live our lives, make decisions about people, form guiding philosophies, and construct entire narratives on the basis of memories that are often dead wrong.

When we use our memories to strengthen our narratives, it causes huge dissonance when those memories are revealed to be false. It often requires a rewriting of the entire narrative. This is incredibly hard for humans, provoking what can be thought of as an existential crisis. If I am who I am because of my experiences, what happens when those experiences cease to exist? Do I, in a sense, cease to exist as well?

Admitting Mistakes

In order to be able to admit mistakes, to correct the spiraling self-justification that can have devastating consequences for ourselves and others, we need to accept that “something we did can be separated from who we are, and who we want to be. Our past selves need not be a blueprint for our future selves. The road to redemption starts with the understanding that who we are includes what we have done but also transcends it, and the vehicle for transcending it is self-compassion.”

This clears the path. It allows us to let go of the past and focus on building the future. More of this would result in an inevitable boon to society.

What is needed is a deep understanding not only of what went wrong then but also of what is going wrong right now, the better to prepare for what could go wrong with current decisions.

The authors argue that is a problem, particularly endemic to North America, that we associate mistakes with failure. We need to shift the thinking, to see mistakes as part of the learning process, necessary steps on the road to making things better.

The amazing thing is, most of us find it refreshing and positive when people admit mistakes. We long to hear our politicians or intellectual leaders or even our relatives say ‘yeah, I messed up. No excuses, I own it, and now I want to fix it’. Hearing this frees us and allows us to do the same.

So try it out. Right now. Think about a mistake you’ve made recently. We all have; with our kids, our partners, our colleagues. Pick one. Think about the narrative you told yourself in the aftermath. Now kick that narrative to the curb and leave it there. You don’t need it anymore. Then find a mirror. Admit to yourself you made a mistake.

Last step. Go find the person you hurt and own up to your mistake. I know this sounds scary, but the more we do this the more authentic and rewarding our relationships will be.

Richard Restak: Mozart’s Memorization of Miserere and Improving your Memory with Visual Chess

In 1956 George Miller, a Princeton University psychologist, set out an important principle that you’ve probably heard of in a paper titled “The Magical Number Seven, Plus or Minus Two.”

Miller revived an observation made by Scottish Philosopher William Hamilton. After throwing marbles on a floor, “you will find it difficult to view at once more than six, or seven at most, without confusion.”

More items, however, Hamilton noted can be remembered when they are “chunked.”

In the fascinating book Mozart’s Brain and the Fighter Pilot: Unleashing Your Brain’s Potential, Richard Restak shows us how to improve the performance of our brain by improving the performance of our memory through better “chunking”.

Memory Pegs

One can remember long strings of numbers, letters, or words when they are reconstructed into meaningful patterns, also known as “memory pegs.”

One that is familiar to most of us concerns the position of the planets in relations to the sun, which is remembered by the mnemonic aid “My Very Educated Mother Just Sent Us Nine Pizzas.” This sequence reminds us of the planetary order: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. (Before you ask, I haven’t abandoned Pluto just yet.)

Chunking is how a lot of inexplicable things happen with memory.

Consider Mozart’s memorization of the Miserere, written more than a century earlier by the Italian composer Gregorio Allegri.

In 1770, while in his early teens, Mozart visited the Vatican’s Sistine Chapel and heard this choral work performed on only two occasions. He then sat down and wrote out the entire score from memory. We know this because only three copies of the score existed at the time and its owner, the Vatican, forbade any publication. Thus, Mozart had no source for re-creating the score other than his own recall of the performances he had attended. Now that the score is freely available, Mozart’s accomplishment seems less remarkable. Musicians have told me that the Miserere is harmonically quite conventional for the period. Anyone who shared Mozart’s familiarity with similar musical forms would not find it a great challenge to chunk large parts of the work around these standard structures.

A further addition to the story comes from John Sloboda’s book The Musical Mind. “Mozart’s feat of memory does not involve inexplicable processes which set him apart from other musicians,” he writes. “Rather it distinguished him as someone whose superior knowledge and skill allow him to accomplish something rapidly and supremely confidently which most of us can do, albeit less efficiently, and on a smaller scale.”

The Memory Palace is a form of chunking, which propelled Joshua Foer to the world Memory Champion. The concept is believed to be first suggested by the Greek poet, Simonides of Ceos who suggested, as Restak tells us, “an imaginary walk through one’s own house or town square. At selected locations along the walk, Simonides would conjure up a vivid mental picture of the location to remind him of a point he wished to make in a speech.”

Basically link what you want to remember with a specific location you know well and a vivid image. Why a vivid image?

The reason comes from Ad Herennium, which dates to 82 B.C. The unknown author writes:

[O]rdinary things easily slip from the memory while the striking and the novel stay longer in the mind. We ought then to set up images that can adhere longest in memory. And we shall do so if we establish similitudes as striking as possible; if we set up images that are not many or vague but active; if we assign to them exceptional beauty or singular ugliness.

Bizarre Linking

Restak also offers another, “complementary memory method (that) involves linking together dramatic and often bizarre images that represent the memorized material.”

In their book, (The Memory Book) Lorrayne and Lucas give several examples of the use of stark images to provide memory clues to overcome absentmindedness. For instance, if you want to be sure you don’t leave your umbrella at the office, they suggest the following “ridiculous” image: “As you arrive and put your umbrella away, associate it to the first thing you see or do as you’re leaving the office. If you ride in an elevator picture an umbrella operating it.”

The brain weaves together the right and left hemispheres into one total experience.

Visualization exercises strengthen the powers of the right hemisphere. And when you bring the left hemisphere into play, the integration between the hemispheres is enhanced.

Intensely studying art can increase the powers of visual perception, something that was well-known to the ancients, who used art to meditate, focus, and hopefully further their quest towards enlightenment.

Asian art, especially Tibetan Buddhist paintings, was created to enhance the powers of visual perception. Buddhist devotees intensely studied the paintings until they could envision the images down to the smallest detail. They believed this act of visualization and intense concentration cleansed and prepared their minds to assume the attributes and wisdom of the beings portrayed in the paintings.

Roberta Smith, a New York Times art critic, said of these Tibetan paintings, “These images are visual exercises of the highest order. Each time you look at them, you see and understand more. . . . They were often tools that helped develop the powers of meditation basic to enlightenment.”

Visual Chess

Restak suggests you do the following exercise to improve your visual acuity by playing “visual chess.”

Most chess masters can manage a game of ‘mental chess’; some of the great masters of the past could play several opponents simultaneously while blindfolded. … Although it’s less demanding than blindfold chess, you’ll find it challenging.

Read into a tape recorder the first dozen moves of a famous chess match. My favorite is the game played in 1858 by American chess prodigy Paul Morphy against Duke Karl Brunswick and Count Isouard during an intermission in the royal box at the opera house in Paris. Whichever game you choose, read the moves slowly and distinctly with a five-second pause between each move. (For the first few efforts, you probably won’t have to read more than a dozen moves.) Then set up the chessboard and begin.

Turn on the tape recorder and mentally make the first move by white, followed by black’s response. Imagine the resulting position of the pieces on the board. Continue the moves until you experience a slight lack of clarity or doubt about the position of the pieces. Focus as keenly as possible. See the pieces in your mind. When you reach the point where you can’t image the board and the position of the pieces, open your eyes and move the pieces until you reach the position where you began to lose clarity. (The best arrangement of all is to have someone moving the pieces as you call out each move; thus, upon opening your eyes, you immediately encounter the exact position where your imaging faltered.) When you can once again establish a clear image of the position, close your eyes again and continue.

If you’re not into chess, you can accomplish the same thing by attempting to complete a crossword puzzle without resorting to pencil or pen.

As you come up with the correct words, visualize them on the grid and retain them in your memory. See how far you can get before you have to stop. Since this is a test of visualization rather than a test of your talent for solving crossword puzzles, have the solution readily at hand so you can mentally fill in the missing words and go on with visualizing.

These exercises are designed to prime the frontal lobes, which help with concentration and focus, the visual association areas, and the hippocampus and its attendant connections (which govern memory). Over time, disciplined practice can yield some very interesting and worthwhile improvements.

Mozart’s Brain and the Fighter Pilot goes on to explore 27 other ideas to improve your memory and the operation of your brain.

Memory and the Printing Press

You probably know that Gutenberg invented the printing press. You probably know it was pretty important. You may have heard some stuff about everyone being able to finally read the Bible without a priest handy. But here’s a point you might not be familiar with: The printing press changed why, and consequently what, we remember.

Before the printing press, memory was the main store of human knowledge. Scholars had to go to find books, often traveling around from one scriptoria to another. They couldn’t buy books. Individuals did not have libraries. The ability to remember was integral to the social accumulation of knowledge.

Thus, for centuries humans had built ways to remember out of pure necessity. Because knowledge wasn’t fixed, remembering content was the only way to access it. Things had to be known in a deep, accessible way as Elizabeth Eisenstein argues in The Printing Press as an Agent of Change:

As learning by reading took on new importance, the role played by mnemonic aids was diminished. Rhyme and cadence were no longer required to preserve certain formulas and recipes. The nature of the collective memory was transformed.

In the Church, for example, Eisenstein talks of a multimedia approach to remembering the bible. As a manuscript, it was not widely available, not even to many church representatives; the stories of the bible were often pictorially represented in the churches themselves. Use of images, both physically and mentally, was critical to storing knowledge in memory: they were used as a tool to allow one to create extensive “memory palaces” enabling the retention of knowledge.

Not only did printing eliminate many functions previously performed by stone figures over portals and stained glass in windows, but it also affected less tangible images by eliminating the need for placing figures and objects in imaginary niches located in memory theatres.

Thus, in an age before the printing press, bits of knowledge were associated with other bits of knowledge not because they complemented each other, or allowed for insights, but merely so they could be retained.

…the heavy reliance on memory training and speech arts, combined with the absence of uniform conventions for dating and placing [meant that] classical images were more likely to be placed in niches in ‘memory theatres’ than to be assigned a permanent location in a fixed past.

In our post on memory palaces, we used the analogy of a cow and a steak. To continue with the analogy used there, imagining that your partner asks you to pick up steak for dinner. To increase your chances of remembering the request, you envision a cow sitting on the front porch. When you mind-walk through your palace, you see this giant cow sitting there, perhaps waving at you (so unlike a cow!), causing you to think, ‘Why is that cow there–oh yeah, pick up steak for dinner’.

Before the printing press, it wasn’t just about picking up dinner. It was all of our knowledge. Euclid’s Elements and Aristotle’s Politics. The works of St. Augustine and Seneca. These works were shared most often orally, passing from memory to memory. Thus memory was not as much about remembering in the ages of scribes, as it was about preserving.

Consequently, knowledge was far less shared, and then only to those who could understand it and recall it.

To be preserved intact, techniques had to be entrusted to a select group of initiates who were instructed not only in special skills but also in the ‘mysteries’ associated with them. Special symbols, rituals, and incantations performed the necessary function of organizing data, laying out schedules, and preserving techniques in easily memorized forms.

Anyone who’s played the game “Telephone” knows the problem: As knowledge is passed on, over and over, it gets transformed, sometimes distorted. This needed to be guarded against, and sometimes couldn’t be. As there was no accessible reference library for knowledge, older texts were prized because they were closer to the originals.

Not only could more be learned from retrieving an early manuscript than from procuring a recent copy but the finding of lost texts was the chief means of achieving a breakthrough in almost any field.

Almost incomprehensible today, “Energies were expended on the retrieval of ancient texts because they held the promise of finding so much that still seemed new and untried.” Only by finding older texts could scholars hope to discover the original, unaltered sources of knowledge.

With the advent of the printing press, images and words became something else. Because they were now repeatable, they became fixed. No longer individual interpretations designed for memory access, they became part of the collective.

The effects of this were significant.

Difficulties engendered by diverse Greek and Arabic expressions, by medieval Latin abbreviations, by confusion between Roman letters and numbers, by neologisms, copyists’ errors and the like were so successfully overcome that modern scholars are frequently absent-minded about the limitations on progress in the mathematical sciences which scribal procedures imposed. … By the seventeenth century, Nature’s language was being emancipated from the old confusion of tongues. Diverse names for flora and fauna became less confusing when placed beneath identical pictures. Constellations and landmasses could be located without recourse to uncertain etymologies, once placed on uniform maps and globes. … The development of neutral pictorial and mathematical vocabularies made possible a large-scale pooling of talents for analyzing data, and led to the eventual achievement of a consensus that cut across all the old frontiers.

A key component of this was that apprentices and new scholars could consult books and didn’t have to exclusively rely on the memories of their superiors.

An updated technical literature enabled young men in certain fields of study to circumvent master-disciple relationships and to surpass their elders at the same time. Isaac Newton was still in his twenties when he mastered available mathematical treatises, beginning with Euclid and ending with an updated edition of Descartes. In climbing ‘on the shoulders of giants’ he was not re-enacting the experience of twelfth-century scholars for whom the retrieval of Euclid’s theorems had been a major feat.

Before the printing press, a scholar could spend his lifetime looking for a copy of Euclid’s Elements and never find them, thus having to rely on how the text was encoded in the memories of the scholars he encountered.

After the printing press, memory became less critical to knowledge. And knowledge became more widely dispersed as the reliance on memory being required for interpretation and understanding diminished. And with that, the collective power of the human mind was multiplied.

If you liked this post, check out our series on memory, starting with the advantages of our faulty memory, and continuing to the first part on our memory’s frequent errors.

Mozart’s Brain and the Fighter Pilot

To get smarter, we need to exercise our cognitive powers – in the same way that we strengthen our bodies by exercising our muscles. To do this, we need to put ourselves in rich and varied environments, learn new things, and strengthen our memory.


Most of us want to be smarter but have no idea how to go about improving our mental apparatus. We intuitively think that if we raised our IQ a few points that we’d be better off intellectually. This isn’t necessarily the case. I know a lot of people with high IQs that make terribly stupid mistakes. The way around this is by improving not our IQ, but our overall cognition.





Improving Our Cognitive Power

To improve the brain, we need to exercise our cognitive powers. Most of us believe that physical exercise helps us feel better and live healthier, yet how many of us exercise our brain? As with our muscles and our bones, “the brain improves the more we challenge it.”




“We are,” Restak writes, “what we remember.” And poor memories are not limited to those who suffer from Alzheimer’s disease. While some of us are genetically endowed with superlative memories, the rest of us need not fear.



Learning and Knowledge Acquisition

When we learn something new, we expand the complexity of our brains. We literally increase our brainpower.


Too many of us can’t remember these days, because we’ve outsourced our brain. One of the most common complaints at the neurologist’s office for people over forty is poor memory. Luckily most of these people do not suffer from something neurological, but rather the cumulative effect of disuse — a graceful degradation of their memory.


Before the printing press, we had to use our memories. Epics such as The Odyssey and The Iliad were recited word-for-word. Today, however, we live in a different world, and we forget that these things were even possible. Information is everywhere. We need not remember anything, thanks to technology. This helps and hinders the development of our memory.




From this, we can draw a reasonable conclusion: if you stop learning, mental capacity declines.


The Better Network: Your Brain or the Internet




Cognitive researchers now accept that it may not be the size of the human brain, which gives it such unique abilities — other animals have large brains as well. Rather, it’s our structure; the way our neurons are structured, arranged and linked.

The more you learn, the more you can link. The more you can link, the more you increase the brain’s capacity. And the more you increase the capacity of your brain, the better able you’ll be to solve problems and make decisions quickly and correctly. This is real brainpower.

Multidisciplinary Learning



This brings the entire range of ideas into play, rather than just silos of knowledge from human-created specialties. Charlie Munger and Richard Feynman would probably agree that such over-specialization can be quite limiting. As the old proverb goes, the frog in the well knows nothing of the ocean.

Charles Cameron, a game theorist, adds to this conversation:


Mozart’s Brain and the Fighter Pilot goes on to provide 28 suggestions and exercises for enhancing your brain’s performance, a few of which we’ll cover in future posts.

Remembering More of Everything: The Memory Palace

it’s often because it doesn’t have anything to stick to.”

— Joshua Foer









The Memory Palace











Got it?


Four hours from now when you leave work to head home you’ll remember you had to pick something up from the grocery store. When you take a trip to your memory palace, walk up the drive and gaze at your front porch. What do you think you are more likely to remember? The packaged steaks, that you see all the time? Or the gum chewing cow we created?




PAO: Person – Action – Object








