Your Central Executive

4. Your Central Executive. Finally, your central executive pulls together
and integrates the information from these three other systems—
the visuospatial sketchpad, the phonological loop, and the
episodic buffer. In addition, this executive function helps to determine
where you are going to place your attention and suppresses
irrelevant or unimportant information, so you can stay focused on
what’s important and not be distracted by what isn’t. It also helps
you plan strategies and coordinate behavior, so you decide what to
do next and what not to do. Then you don’t get pulled away from
what you most want to do.26
Think of this as the top executive or senior manager in charge of
all of these other systems, which doesn’t store information itself.
Rather, like the executive of a company, it sets the priorities for what
these other sections of your memory should be doing. Or as Matlin
puts it: ‘‘like an executive supervisor in an organization . . . the [central]
executive decides which issues deserve attention and which
should be ignored. The executive also selects strategies, figuring out
how to tackle a problem.’’27
For example, when you decide what task you are going to work
on at work and seek to remember what your boss has instructed you
to do, along with what else you know about how to best perform
the task, that’s your central executive pulling together what is most
relevant from the other sections of your working and long-term
memory, so you can better perform the task.
* * *
So there you have it—the basic structure of how your memory
works, according to the latest research from cognitive psychologists.
In subsequent chapters, I’ll be drawing on this model as I describe
different techniques for optimizing your memory. Accordingly, you’ll
find techniques for strengthening your ability to work with images
(your visuospatial sketchpad), with verbal and audio input (your
phonological loop), with your ability to temporarily coordinate the
input from the other components of your memory (your episodic
buffer), and with your ability to use all of this information in a mindful,
coordinated, and strategic way (your central executive). 26

Your Episodic Buffer

3. Your Episodic Buffer. This section of your working memory is
essentially a temporary storehouse where you can collect and combine
information that you have gotten from your visuospatial sketchpad
and phonological loop, along with your long-term memory.24
Think of this like a notebook or page in a word processing program
where you are working with sentences, graphic images, and then
thinking about what else you would like to add from what you already
know. As Margaret Matlin describes it, the episodic buffer ‘‘actively
manipulates information so that you can interpret an earlier
experience, solve new problems, and plan future activities.’’25
For example, say a co-worker says something to you at work that
offends you. This is where you might consider the words the person
just said, the context in which he said it, and take into consideration
what you remember from how this co-worker has acted toward you
before (which comes from your long-term memory). Then, this episodic
buffer helps you quickly decide what to do in light of how you
have interpreted this offending remark.

Your Phonological Loop

2. Your Phonological Loop. Just as your visuospatial sketchpad
stores images briefly while you are working with them, your phonological
loop stores a small number of sounds for a brief period.21 Generally,
researchers have found that you can hold about as many
words as you can mentally pronounce to yourself in 1.5 seconds, so
you can remember more short words than long ones.22
A good example of how this works is when you are trying to
remember what you or someone else has just said. Without memory
training to put those words in long-term memory, you will normally
only be able to clearly remember back what has been said in the last
1.5 seconds, though you will remember the gist of what you or the
other person has said. Also, because of this 1.5-second limit, you will
be better able to remember more shorter names than longer ones,
such as when you are introduced to a number of people at a business
mixer or cocktail party. It’s simply much easier to remember names
like Brown and Cooper than longer and more unusual ones.
You’ll also find that just as working with different types of visual
imagery can cause interference, so can working with different types
of audio sounds. For example, if you are trying to remember a phone
number and someone says something to you, that can interfere with
your ability to remember that number. But if you are looking at
something while you are trying to remember the number, that won’t
interfere as long as you continue to pay attention to remembering
that number, since your visual observation is processed in your visuospatial
sketchpad.
Then, too, just as similar visual imagery can cause memory errors,
so can hearing similar sounding words or numbers, such as
when you find yourself meeting a Margaret, Maggie, and Mary at a
party. The names can blend together in your mind and you have
trouble remembering who is who. Or say you are trying to remember
a phone number you have gotten from a message so you can write it
down.Well, if you are given two phone numbers to remember—such
as this is my land line and this is my cell phone—the two numbers
can interfere with each other, so you might mix up numbers or just
not remember at all. Or if you are trying to recall and write down a
number that’s close to another phone number you already know,
that could interfere with your ability to remember the new one.
But the reason that visual images won’t interfere with trying to
remember words or other audio sounds, as long as you are attending
to both, is that the audio processing occurs in a different section of
your brain—in the left hemisphere of your brain, which is the side
of your brain that handles language. Plus the auditory information
is stored in the parietal lobe of your brain, though when you practice
working with this information, your frontal lobe section that processes
speech will become active too.

Your Visuospatial Sketchpad

1. Your Visuospatial Sketchpad. Consider this a drawing pad in
which you place visual images as you see something or where you
sketch the images you create in your mind when someone tells you
something.20 For example, as you watch a TV show or movie, the
series of images you see get placed on this sketchpad, and some of
the most memorable will move on to your long-term memory. You
won’t remember every detail, since there are thousands of such images
zipping by in a minute. But your memory for these images will
string them together—and as you improve your memory for visual
details, you will be able to notice and remember more.
This is also the section of your memory that works on turning
what you are hearing or thinking about into visual images. For example,
as you read or hear a story, this is where you create images
for what you are listening to, so it becomes like a movie in your
mind. Or suppose you are trying to work out a math problem in your
mind. This is where you would see the numbers appear, such as if
you are trying to multiply 24 33 and don’t already have a multiplication
table for that problem in your mind. You would see the individual
rows as you multiply and then add them together.
However, while you might be able to see and keep in memory
one image very well, you will have less ability as the number of images
increase, and you may find that one image interferes with another.
For example, if you are driving while trying to think about
and visualize the solution to some kind of problem, your thoughts
could well interfere with your driving. I found this out for myself
when I was trying to multiply some numbers in my mind and took
the wrong turn-off because I was distracted by seeing the problem
in my mind. But if you are only listening to music on the radio or to
someone speaking without forming images, that will not interfere—
or at least to the same degree.
You might think of this process of trying to work with more and
more images at the same time as looking at the windows on a computer
screen. As you add more windows to work with at the same
time, the individual windows get smaller and smaller, as do the images;
you are less able to see what is in each image distinctly, and
your attention to one window may be distracted by what is flashing
by in another.
Intriguingly, brain researchers (also called neuroscientists) have
found that these images you see in your visuospatial sketchpad correspond
to real places in your brain. As neuroscientists have found,
when you work with a visual image, it activates the right hemisphere
of your cortex, the top section of your brain, and in particular they
activate the occipital lobe, at the rear of your cortex. Then, as you
engage in some mental task involving this image, your frontal lobe
will get in on the action, too.
Researchers have been able to tell what part of the brain is associated
with different types of thinking by using PET (positron emission
tomography) scans, where they measure the blood flow to the
brain by injecting a person with a radioactive chemical just before
they perform some kind of mental task. They find that certain
sections of the brain have more blood flow, indicating more activity
there for different types of mental tasks. 23

Some Barriers to Remembering

Researchers have found that there are some cognitive barriers to a
better memory that will slow you down. One is having longer names
or words, especially when they have odd spellings and many syllables.
Even trying to take a mental picture of the name or word may
not work, because saying it verbally to yourself is an important part
of putting a new name or word into your memory.
For example, I found the long words and names a real stumbling
block when I tried to learn Russian two times—once when I was
still in college, and later when I was taking occasional classes at a
community college in San Francisco. I could even manage seeing the
words in Cyrillic, converting them into their English sound equivalent.
But once the words grew to more than seven or eight letters, I
had to slow down to sound out each syllable and it was a real struggle
to remember. Had I known the principle of chunking back then,
I’m sure I would have caught on much sooner.
Another barrier to memory is interference; if some other name,
word, or idea that you already have in your working memory is similar
to what you are learning, it can interfere with your remembering
something new correctly. And the more similar the two items, the
greater the interference16 and the more likely you are to mix them
up. Again, researchers have come to these conclusions by looking at
words (or even nonsense words) and pictures, and asking subjects
to remember these items after learning a series of similar items. But
you can take steps to keep what you have learned before from interfering
with what you learn in the future. As you’ll discover in Chapter
5 on paying attention, you can stop the interference by intensely
focusing on what you want to remember and turning your attention
away from what is similar and interfering with your memory now.

The Power of Your Working Memory

How much information can you actually hold in your working memory—
what can you deal with on your desktop at one time? Well,
when researchers began studying the working memory, they came
up with some of the findings that are still accepted and incorporated
into models of memory today.
One of these findings is the well-known Magic Number Seven
principle, which was first written about by George Miller in 1956 in
an article titled ‘‘The Magical Number Seven, Plus or Minus Two:
Some Limits on Our Capacity for Processing Information.’’ He suggested
that we can only hold about seven items, give or take two—or
five to nine items—in our short-term memory (which was the term
originally used for the working memory). However, if you group
items together into what Miller calls ‘‘chunks’’—units of short-term
memory composed of several strongly related components—you can
remember more.13 And in Chapter 12 you’ll learn more about how to
do your own chunking to improve your memory capacity.
You can see examples of how this Number Seven principle and
chunking work if you consider your phone number and social security
number. One reason the phone number was originally seven
numbers and divided into two groups of numbers is because of this
principle—then when the area code was added, the phone number
was split up or chunked into three sections. Similarly, your social
security number is divided into three chunks. And when you look at
your bank account, you’ll see that number is chunked up into several
sections. As for memory experts who can reel off long strings of
numbers, they do their own mental chunking so they can remember.
They don’t have a single, very long string of numbers in their mind.
However you chunk it, though, whatever material comes into
your working or short-term memory is frequently forgotten if you
hold it in your memory for less than a minute14—a finding repeatedly
confirmed by hundreds of studies by cognitive psychologists.
That’s why you normally have to do something to make that memory
memorable if you want to retain it.
Yet, while you want to improve your memory for things you
want to remember, you don’t want to try to improve it for everything.
Otherwise your mind would be so hopelessly cluttered, you
would have trouble retrieving what you want. For example, think of
the many activities and thoughts you experience each day, many of
them part of a regular routine. Well, normally, you don’t want to
remember the minutia of all that, lest you drown in an overwhelming
flood of perceptual data. It would be like having an ocean of
memories, where the small memory fish you want to catch easily
slip away and get lost in the vast watery expanses. But if something
unusual happens—say a robber suddenly appears in the bank where
you are about to a make a deposit—then you do want to remember
the event accurately. So that’s when it’s important to focus and pay
attention in order to capture that particular memory, much like reeling
in a targeted fish.
Memory researchers have also found that your short-term or
working memory is affected by when you get information about
something, which is called the ‘‘serial position effect.’’ In general,
whatever type of information you are trying to memorize, you will
better remember what you first learn (called the ‘‘primacy effect’’) or
what you learn most recently (called the ‘‘recency effect’’).15 When
psychologists have tested these effects by giving numerous subjects
lists of words that vary in word length and the number of words, the
results show a similar pattern. Subjects can generally remember two
to seven items and are most likely to remember the most recent
items first. In turn, you can use that principle when you want to
remember a list of anything, from a grocery list to a list of tasks to
do.

From Perception to Working Memory to Long-Term Memory

Memory starts with an initial perception as you are paying attention
to something, whether your attention is barely registering the perception
or you are really focused on it. So, as described in Chapter 5,
one of the keys to improving your memory is paying more attention
in the first place.
The next stop is your working memory, which is your brief, initial
memory of whatever you are currently processing. A part of this
working memory acts as a central processor or coordinator to organize
your current mental activities.11 You might think of the process
as having a screen on your computer that has the information you
are currently reading or writing. As psychologist Margaret Matlin
explains it, your ‘‘working memory lets you keep information active
and accessible, so that you can use it in a wide variety of cognitive
tasks.’’12 Your working memory decides what type of information is
useful to you now, drawing this out from the very large amount of
information you have—in your long-term memory or from the input
you have recently received. Think of yourself sitting in front of a
desk with expansive drawers representing what’s in your long-term
memory and a cluttered top of your desk representing what’s in your
working memory. Then, you as the central executive (the working
memory) decide what information you want to deal with now and
what to do with it. 17

Current Thinking on Memory

While the Atkinson-Shiffrin model was extremely popular at the
time, today psychologists think of sensory memory as a part of perception,
held only so briefly in consciousness, and they think of
short-term and long-term memory as more part of a continuum,
with no clear distinction between them.10 Still, psychologists usually
distinguish between these two types of memory, and I will too, in
discussing ways you can improve both types of memory. In fact, with
the development of neuroscience and the recognition that we are
engaging in multiple forms of mental processing at the same
time—a process called ‘‘parallel distributed processing’’—psychologists
have recognized that memory is much more complex than earlier
scientists might have thought. Currently, the commonly accepted
model views memory in a more dynamic way, in which a central
processing system coordinates different types of memory input,
which may be visual or auditory or both. After taking into consideration
personal knowledge and experience, this central processor
passes selected bits of memory from the working memory into the
long-term memory. It’s a model that I’ll be using as a backdrop to
different types of memory techniques that are designed to make improvements
in each area of processing. In the next section, I’ll explain
in a little more detail how this works.

Modern Research on Memory

According to psychologists, building on the work of these early precursors,
cognitive psychology—the study of mental processes, including
memory—really begins in 1956. So the foundations of
modern memory research only go back 50 years. As Margaret W.
Matlin writes in Cognition, an introduction to cognitive psychology,
initially published in 1983 and now in its sixth edition, ‘‘research
in human memory began to blossom at the end of the 1950s. . . .
Psychologists examined the organization of memory, and they proposed
memory models.’’7 They found that the information held in
memory was frequently changed by what people previously knew or
experienced—a principle that can also be applied in improving your
memory. For example, if you can tie a current memory into something
you already know or an experience you have previously had,
you can remember more.
For a time, psychologists studying memory used an informationprocessing
model developed by Richard Atkinson and Richard Shiffrin
in 1968 that came to be known as the Atkinson-Shiffrin model.
While some early memory improvement programs were based on
this model, it has since been replaced by a new model that is discussed
in the next section.
In the Atkinson-Shiffrin model, memory is viewed as a series of
distinct steps, in which information is transferred from one memory
storage area to another.8 As this model suggests, the external input
comes into the sensory memory from all of the senses—mostly visual
and auditory, but also from the touch, taste, and smell—where it is
stored for up to two seconds and then quickly disappears unless it is
transferred to the next level. This next level is the short-term memory
(now usually referred to as ‘‘working memory’’), which stores
information we are currently using actively for up to about 30 seconds.
Finally, if you rehearse this material, such as by saying the
information over and over in your mind, it goes on into the longterm
memory storage area, where it becomes fairly permanent.9
Thus, if you want to improve your own memory, it is critical to
rehearse any information you want to transfer into your long-term
memory and thereby retain. Such rehearsal can take the form of selftalk,
where you say the ideas to remember over and over again in
your mind to implant them in your long-term memory. Graphically,
this process of moving memory from sensory to short-term to longterm
memory looks something like this:
Sensory Memory Short-Term Memory Long-Term Memory

The Beginnings of Studying Memory

Even before philosophers and other theorists began to study human
thought processes, including memory, memory played an extremely
important part in the development of human society. It was critical
for teaching new skills, customs, and traditions. Before the development
of printing, people had to remember many things that now are
recorded on the printed page or can be shared through audio and
video recordings. For example, consider all of the rituals, songs, and
stories that people had to learn and then pass on to others. This
might be like learning the contents of dozens of books. Anthropologists
have estimated the extensive scope of such learning by speaking
with the culture bearers of once nonliterate cultures and
speculating as to what kind of learning might have been passed on
by distant cultures.
Then, to skip ahead to about 2,300 years ago, the Greek philosopher
Aristotle was one of the first to systematically study learning
and memory. Besides proposing laws for how memory works, he also
described the importance of using mental imagery, along with experience
and observation—all of which are key aids for remembering
anything.
However, the formal study of memory by psychologists didn’t
begin until the late 19th century, when Wilhelm Wundt set up a
laboratory in Leipzig, Germany, and launched the discipline of psychology,
based on studying mental processes through introspection
or experimental studies.1 There, along with studying other mental
processes, he began the first studies of human memory.
Many of these memory studies used assorted clinical trials,
which may seem a far cry from the practical tips on memory that are
described in this book. But the work of these researchers helped to
discover the principles of how we remember that provide the theoretical
foundation for what works in effective memory training
today. For example, back in 1894, one of the first memory researchers—
and the first woman president of the American Psychological
Association, Mary Whiton Calkins—discovered the recency effect,
the principle that we more accurately recall the last items we learn.2
These early researchers generally used nonsense syllables to determine
what words a person would best remember after a series of
tests of seeing words and trying to recall them, but the recency principle
still applies when you try to remember something in day-to-day
life. Want to better remember something? Then, learn it or review it
last when you are learning a series of things at the same time.
The well-known psychologist William James was also interested
in memory, discussing it in his 1890 textbook Principles of Psychology,
along with many of the cognitive functions that contribute to memory,
such as perception and attention. He even noted the ‘‘tip-of-the-
tongue’’ experience that we have all had: trying to recall a name that
seems so close—but not quite able to grasp it.3
During the first half of the 20th century the behaviorists, with
their focus on outward, observable behaviors and the stimuli contributing
to different behaviors, dominated psychological research in
the United States. They weren’t interested in mental processes or in
introspection about them, though their methods of measurement
were later adopted by memory researchers.4
But in Europe, in the early 1900s, Gestalt psychology got its start.
It brought a new perspective of looking at meaning and at the way
humans organize what they see into patterns and wholes. They
pointed up the importance of the overall context for learning and
problem solving, too.5 It’s an approach that is very relevant for understanding
ways to improve memory; their work helped us understand
that by creating patterns and providing a meaningful context
to stimulate better encoding of a memory in the first place, that
memory could more easily be retrieved later. For example, Frederick
C. Bartlett, a British psychologist, who published Remembering: An
Experimental and Social Study in 1932, who used ‘‘meaningful material’’
such as long stories (rather than random words or nonsense
syllables), found that people made certain types of errors in trying to
recall these stories for the researchers. Significantly, these were errors
that often made the material more consistent with the subject’s
personal experience, showing the way meaning shapes memory.6
Like the recency findings discussed above, these findings—that you
will remember something better if you can relate it to your own experience—
are the basis for some of the techniques described later in
the book.

How Your Memory Works

To know how to improve your memory, it helps to have a general
understanding of how your memory works. I have created specific
exercises based on this knowledge, exercises that will help you improve
in each of the areas of your memory.
The roots for the way we think about memory today actually
have a long history, dating at least back to the time of the Greeks,
and perhaps earlier. Accordingly, I have included a little history
about the way psychologists have thought about memory that has
developed into the model of memory that psychologists commonly
hold today and that I use in this book.