Monday, December 25, 2006


From the time when man first began to depend on his mind for
coping with the environment, the possession of an excellent
memory has placed individuals in positions of both command
and respect. The amazing feats in remembering accomplished
by particular people were so impressive that they have become
It is difficult to say exactly when and where the first inte-
grated ideas on memory arose. It is reasonable to state, how-
ever, that the first sophisticated concepts can be attributed to
the Greeks some 600 years before the birth of Christ.
As we look back on them now, these 'sophisticated' ideas
were surprisingly naive, especially since some of the men
proposing them are numbered among the greatest thinkers the
world has ever known!
In the 6th century B.C., Parmenides thought of memory as
being a mixture oflightand dark or heat and cold! He thought
that as long as any given mixture remained unstirred, the
memory would be perfect. As soon as the mixture was altered,
forgetting occurred.
In the 5th century B.C. Diogenes ofAppollonia advanced a
different theory. He suggested that memory was a process
which consisted of events producing an equal distribution of.
air in the body. Like Parmenides he thought that when this
equilibrium was disturbed forgetting would occur.
Not surprisingly, the first person to introduce a really major
idea in the field of memory was Plato, in the 4th century B.C.
His theory is known as the Wax Tablet Hypothesis and is still
accepted by some people today, although there is growing
disagreement. To Plato the mind accepted impressions in the
same way that wax becomes marked when a pointed object is
moved around on its surface. Once the impression had been
made Plato assumed it remained until, with time, it wore away,
leaving a smooth surface once more. This smooth surface was,
of course, what Plato considered to be complete forgetting—the
opposite aspects ofthe same process. As will become clear later,
many people now feel that they are actually two quite different
Shortly after Plato, Zeno the Stoic slightly modified Plato's
ideas, suggesting that sensations actually 'wrote' impressions
on the wax tablet. When Zeno referred to the mind and its
memory he, like the Greeks before him, did not place it in any
particular organ or section of the body. To him and to the
Greeks 'mind' was a loose and very unclear concept.
The first man to introduce a more scientific terminology
was Aristotle, in the late 4th century B.C. He maintained that
the language previously used was not adequate to explain the
physical aspects of memory. In applying his new language
Aristotle attributed to the heart most of the functions that we
properly attribute to the brain. Part of the heart's function, he
realised, was concerned with the blood, and he felt that
memory was based on the blood's movements. He thought
forgetting to be the result of a gradual slowing down of these
Aristotle made another important contribution to sub-
sequent thinking on the subject ofmemory when he introduced
his laws ofthe association of ideas. The concept of association
of ideas and images is now generally thought to be of major
importance to memory. Throughout Speed Memory this con-
cept will be discussed, developed and applied.
In the 3rd century B.C. Herophilus introduced to the discus-
sion 'vital' and 'animal' spirits. He considered the higher order
vital spirits to be located in the heart. These higher order
spirits produced the lower order animal spirits, which included
the memory, the brain, and the nervous system. All ofthese he
thought to be secondary in importance to the heart!
It is interesting to note that one reason advanced by Hero-
philus for man's superiority over animals was the large number
of creases in man's brain. (these creases are now known as
convolutions of the cortex). Despite thefact ofhis observation,
Herophilus offered no reason for his conclusion. It was not until
the 19th century, over 2,000 years later, that the real import-
ance of the cortex was discovered.
In summary, the Greeks made the following significant
contribution: they were the first to seek a physical as opposed
to a spiritual basis for memory; they developed scientific con-
cepts and a language structure that helped the development of
these concepts; and they contributed the Wax Tablet hypo-
thesis which suggested that memory and forgetting were
opposite aspects of the same process.
Surprisingly, the contributions ofthe Romans were minimal.
The major thinkers of their time, including Cicero in the 1st
century B.C. and Quintilian in the 1st century A.D., accepted
without question the Wax Tablet concept of memory, and did
little further work.
Their major contribution was in the development ofmemory
systems. It was they who first introduced the idea of a Link
system and a Roomsystem, both of which will be described in
later chapters.
TheInfluenceoftheChristian Church
The next major contributor to the progress of ideas on
memory was the great physician Galen in the 2nd century A.D.
He located and delineated various anatomical and physiological
structures, as well as further investigating the function and
structure of the nervous system.
Like the later Greeks, he assumed that memory and mental
processes were part of the lower order of animal spirits. These
spirits he thought were manufactured in the sides ofthe brain,
and it was consequently here that memory was seated.
Galen thought that air was sucked into the brain, mixing
with the vital spirits. This mixture produced animal spirits
which were pushed down through the nervous system, enabl-
ing us to feel and taste, etc.
Galen's ideas on memory were rapidly accepted and con-
doned by the Church which at this time was beginning to exert
a great influence. His ideas became doctrine, and on that
account little progress was made in the field for 1,500 years.
This mental suppression stifled some of the greatest minds
that philosophy and science has produced!
St. Augustine in the 4th century A.D. accepted the Church's
ideas, considering memory to be a function of the soul, which
had a physical seat in the brain. He never expanded on the
anatomical aspects of his ideas.
From the time of St. Augustine until the 17th century there
were virtually no significant developments in ideas on memory,
and even in the 17th century new ideas were restricted by
Even such great a thinker as Descartes accepted Galen's
basic ideas, although he thought that animal spirits were sent
from the pineal gland on special courses through the brain
until they came to the part where memory could be triggered.
The more clear-cut these courses, the more readily, he
thought, would they open when animal spirits travelled
through them. It was in this way that he explained the improve-
ment of memory and the development of what are known as
'memory traces'. A memory trace is a physical change in the
nervous system that was not present before learning. The trace
enables us to recall.
Another great philosopher, who 'went along with the tide'
was Thomas Hobbes, who discussed and consideredthe idea of
memory but contributed little to what had been said before. He
agreed with Aristotle's ideas, rejecting non-physical explana-
tions ofmemory. He did not, however, specify the real nature
of memory, nor did he make any significant attempts to locate
it accurately.
In summary, it is evident from the theories of the 16th
century intellectuals that the influence of Galen and the
Church had been profound. Almost without exception these
great thinkers uncritically accepted primitive ideas on memory.
TransitionalPeriod—The18th Century
One ofthe first thinkers to be influenced by the new surge of
science and by the ideas ofNewton was Hartley, who developed
the vibratory theory of memory. Applying Newton's ideas on
vibrating particles, Hartley suggested that there were memory
vibrations in the brain which began before birth. New sensa-
tions modified existing vibrations in degree, kind, place and
direction. After influence by a new sensation, vibrations
quickly returned to their natural state. But if the same sensa-
tion appeared again the vibrations took a little longer to return.
This progression would finally result in the vibrations remain-
ing in their 'new' state, and a memory trace was established.
Other major thinkers of this period included Zanotti who
was the first to link electrical forces with brain functions, and
Bonnet who developed the ideas of Hartley in relation to the
flexibility ofnervefibres.Themoreoftennerves wereused,the
more easily he thought they vibrated, and the better memory
would then be.
The theories of these men were more sophisticated than
previous ones because they had been largely influenced by
developments in related scientific fields. This interaction of
ideas laid the groundwork for some of the more modern
theories of memory in the 18th century.
The19th Century
With the development of science in Germany in the 19th
century, some important developments occurred. Many of the
ideas initiated by the Greeks were overthrown, and work on
memory expanded to include the biological sciences.
Prochaska finally and irrevocably rejected the age-old idea of
animal spirits, on the ground that it has no scientific basis and
no evidence to support it. He felt that limited existing know-
ledge made speculation on the location of memory in the
brain a waste oftime. 'Spatial localisation may be possible', he
said, 'but we just do not know enough at the moment to make
it a useful idea.' It was not for some 50 years that localising the
area of memory function became a useful pursuit.
Another major theory presented in this century was that of
Flourens, who 'located' the memory in every part ofthe brain!
He said that the brain acted as a whole and could not be inter-
preted as the interaction of elementary parts. His views held
the field of physiology for some time, and it is only recently
that great strides have been made in the development of our
thinking on memory.
Modern Theories
Modern developments in memory have been aided to an
enormous degree by advances in technology and methodology.
Almost without exception psychologists and other thinkers in
this field agree that memory is located in the cerebum, which
is the large area ofthe brain covering the surface ofthe cortex.
Even today however, the exact localisation of memory areas is
proving a difficult task, as is the accurate understanding ofthe
function of memory itself.
Current thought has progressed from Ebbinghaus's work
with learning and forgetting curves at the turn of the century,
to advanced and complex theories.
Research and theory can be roughly divided into 3 main
areas: work on establishing a biochemical basis for memory;
theories which suggest that memory can no longer be consid-
ered as a single process but must be broken down into divi-
sions; and Penfield's work on Brain Stimulation.
Research into the biochemical basis for memory was initiated
by Hyden in the late 1950's. This theory suggests that RNA
(ribonucleic acid), a complex molecule, serves as a chemical
mediator for memory.
RNA is produced by the substance DNA (deoxyrinbonucleic
acid) which is responsible for our genetic inheritance—for
example DNA decides whether your eyes will be blue or
brown, etc.
A number of experiments have been performed with RNA,
lending support to the idea that it does indeed have a lot to do
with the way in which we remember things. For example, if
animals are given certain types of training, the RNA found in
certain cells is changed. And further, ifthe production ofRNA
in an animal's body is stopped or modified, these animals have
been unable to learn or remember.
An even more exciting experiment showed that when RNA
was taken from one rat and injected into another, the second
rat 'remembered' things that he had never been taught, but
which the first rat had!
While research into this aspect of memory is progressing
other theorists are saying that we should stop emphasising
'memory', and concentrate more on the study of 'forgetting'!
It is their position that we do not so much remember, as
gradually forget.
Encompassing this idea is the Duplex theory of remember-
ing and forgetting, which states that there are two different
kinds ofinformation retention: long-term and short-term. For
example, you have probably experienced a different 'feeling'
from the way in which you recall a telephone number which
has just been given to you, and the way in which you recall
your own telephone number.
The short-term situation is one in which the idea is 'in' the
brain but has not yet been properly coded and is therefore
more readily forgotten. In the long-term situation the idea has
been completely coded, filed and stored and will probably
remain for years, if not for life.
Research into direct brain stimulation has been recently
initiated by Dr. Wilder Penfield, a clinical surgeon. When
performing craniotomies (removal of a small section of the
brain) in order to reduce epileptic attacks, Penfield had first to
remove a portion of the skull lying over the side of the brain.
Before operating Penfield conducted, and conducts, a system-
atic electrical stimulation of the open brain, and the patient,
who remains conscious, reports his experience after each
stimulation. In an early case Penfield stimulated the temporal
lobe of the brain and the patient reported a recreated memory
of a childhood experience!
Penfield found that stimulating various areas of the cortex
produces a range ofresponses, but that only stimulation ofthe
temporal lobes leads to reports of meaningful and integrated
experiences. These experiences are often complete in that when
recreated they include the colour, sound, movement, and
emotional content of the original experiences.
Ofparticular interest in these studies is the fact that some of
the memories stimulated electrically by Penfield had been un-
available in normal recall! In addition to this the stimulated
experiences seemed to be far more specific and accurate than
normal conscious recall which tends to be a generalisation. It
is Penfield's beliefthat the brain records every item to which it
pays conscious attention, and that this record is basically
permanent although it may be 'forgotten' in day-to-day living.
That brings us roughly up to date! Looking back over
history, we see that real thinking in this area has been going on
for only a little over two thousand years years, and that for as
many as 1,500 of those 2,000 years virtually no advances were
made. In fact only a few hundred years ofprogressive thought
have passed, and during those years man has progressed from
thinking of memory in terms of spirits and vague concepts, to
tracking it down to a fairly small area in the body.
But even now he is still only at the beginning ofhis search.
Every month more than 80 new articles are published from the
major research centres in the world. It may not be long before
final and dramatic breakthroughs are made.

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