Scientists
have never had any observational basis for making dogmatic statements
asserting that long-term human memories are all stored in the brain.
No scientist has ever done anything like reading a particular memory
from particular neurons in a brain, nor has a scientist ever done anything like causing a
particular memory in a human brain to be evoked when some part of the
brain is electrically stimulated. There have been a few recent claims
to have evoked memories in mice by optical stimulation of the brains
of mice, but such claims are not well founded (for reasons discussed
here). Nonetheless, neurologists and writers on the brain very
commonly commit the intellectual sin of dogmatically proclaiming
unfounded claims about the human brain, asserting that all human
mental activity is due to brain activity. But other people have long
suspected that the human mind is something more than just the brain,
and humans have long tried to gather evidence to support such a
claim.
One
way of trying to substantiate the claim that the mind is more than
the brain is to investigate anomalous psychic phenomena. If it can
be found that the human mind is capable of paranormal experiences or
talents that should be impossible for a brain to produce, that is
evidence that the mind is something more than just the brain.
Investigations into the paranormal have been highly successful in
showing things we cannot explain by brain activity. Experimenters
such as Professor Joseph Rhine accumulated very convincing evidence
for extrasensory perception (ESP), as discussed here. Solid evidence
has been gathered for near-death experiences.
Such
evidence helps to substantiate the idea that there is something like
a human soul that transcends the brain. But there is a very different
way of trying to support the idea that the mind is more than a
product of brain activity. This way involves looking not into
anomalous activity of the human mind, but instead involves an
analysis of perfectly normal, everyday activity of the human
mind. The approach is as follows:
- Make a list of all the capabilities of the human mind, capabilities such as recall of childhood memories, and instant retrieval of a memory.
- Examine the physical capabilities of the human brain, and consider whether it is plausible to maintain that each of the capabilities of the human mind could be achieved by something such as the human brain.
- Whenever a shortfall is found – whenever we find some capability of the human mind that cannot be plausibly explained by the brain – mention this as evidence that the human mind involves something more than just the human brain.
In
three previous posts, I put this strategy to work, and presented
three arguments for believing that human memories cannot all be
stored in the human brain. One
argument
was based on the apparent impossibility of the brain ever naturally
developing all of the many encoding protocols it would need to store
the many different things humans store as memories. The second
argument
was based on the apparent impossibility of explaining how the human
brain could ever be able to instantly recall memories, if memories
are stored in particular locations in the brain, because there would
be no way for the brain to know or figure out where a memory was
stored. The third argument
was based on the fact that humans can remember 50-year old memories,
but scientists have no plausible explanation for how the human brain
can store memories for longer than a single year (partially because of rapid molecular turnover).
There
is still still another argument that can be made along these lines,
another argument based on a capability of the human mind that we
cannot plausibly explain in terms of the human brain. This argument
I will call the insertable sequential memories argument. I can
concisely state the argument as follows: humans have the ability to
store memories involving very long sequences, with an easy ability
for insertion; but the human brain has no structural capability that
can support any such ability, so some of our memories or ideas are
probably stored or created in some mental reality that transcends the
human brain.
First,
let us consider the human ability to remember memories involving long
sequences. An average person shows this ability by being able to
remember the words and notes of many different songs. Each song is a
particular sequence that must be remembered. You might think to
yourself, “I don't know the words of many songs,” but if I were
to have you browse though a list of the 500 most famous songs in
history, you would find that you remembered the words and notes of
lots of them. Of course, on the stage you might see something like a
concert in which a singer sings from memory for 80 minutes. There are
opera singers who have memorized various different roles in the
operatic repertory, which may add up to many hours of words and notes
they have memorized. In his prime years as an opera singer, Placido
Domingo had at least 20 hours of opera roles he could sing upon
demand (and would sometimes fill in for a sick singer, singing one of
the many roles he knew by heart). Similarly, there are a number of
Muslims who have memorized the entire Quran, a book of some 114
chapters or surahs.
We
take this kind of sequential recall for granted, because this is the
way we have always experienced memory working. Similarly, if we were
able to exactly remember every word in each book we had read, we
would take that for granted, and think it nothing special. But we
must ask: does the brain have any type of structure that might allow
such sequential recall to occur, if memories were all stored in the
brain?
There
is no such thing in the brain. The brain consists of billions of
neurons, which are connected together. But there is a reason why the
brain does not seem to have the right type of arrangement to allow
for sequential recall of long sequences of information. The brain
consists of neurons, and each neuron is connected to many other
neurons. There is no “next” for a particular neuron. Neurons are
not arranged in any type of chain-like structure that might support a
recall of sequential memories.
Consider
the physical way in which a book allows for a sequencing of
information. Words are arranged in a linear order on a particular
page. Also, the page order and binding of a book imposes a sequence
on its contents, a sequential ordering we would not see if the pages
were in a jumbled heap.
Or
consider the DNA molecule. The DNA molecule is structured in a way
that allows for a sequential storage of information. A DNA molecule
is rather like an incredibly long and thin rope, in which a sequence
of letters is written on the rope. Within the genetic code used by
DNA, there is a particular sequence that acts as a “stop” signal,
rather like a period in a sentence. With this physical structure, DNA
allows for both a sequential storage of information and a demarcation
of information.
But
consider the human brain. There seem to be no physical
characteristics that might allow for sequential storage of
information. It seems that if you try to store information in the
brain, it should be like tossing a set of alphabet blocks onto a
giant heap in a junkyard.
I
could schematically depict a set of neurons with a visual like the
one below. The little circles represent individual neurons. The
diagram greatly understates the number of connections between
individual neurons.
Consider
the recall of sequential information. Imagine you are trying to
recall a series of words. We might imagine that individual parts of
the sequence are stored in individual neurons – perhaps something a
little like the schematic visual below.
But
how could you recall the sequence in its correct order? Nerve cells
are scattered throughout three dimensional space, with each neuron
having many connections to other neurons. If information is stored in
nerve cells, there would seem to be no way for a sequence to be
stored in a way that would allow a sequential recall involving a long
series, such as happens when an actor playing Hamlet recalls all of
his many lines in the correct order. We can't imagine the brain
simply going from one neuron to the “next” neuron to retrieve a
sequence of information. This is because neurons don't exist in
chains in which a particular neuron has a “next” neuron. Each
neuron is connected to many other neurons.
Below
we see a map of Dupont Circle in Washington D.C.
Once
your car gets on Dupont Circle, there is no “next” place to go.
You've reached an interchange in which there are 10 roads feeding out
of the circular interchange. Similarly, in the photo below we see neurons. Each one of the parts coming out of the nerve cell
is a path that can be traversed from this nerve cell. Such an
arrangement should not offer any support for storing a sequence of
information such as the lines in a play or the notes in a song.
There's no “next” route leading from one neuron to the next
neuron. Every neuron is like Dupont Circle, except that there are
even more paths leading out of the neuron.
Now
let's consider another aspect of human sequential memory: the fact
that it is insertable. What this means is when we memorize a
sequence, it is very easy to insert anywhere a new item in the
sequence.
You
can demonstrate this by trying a test such as this. Most Americans know
the beginning of the song “America the Beautiful”
O
beautiful, for spacious skies
For amber
waves of grain
But
what if we try to recall this sequential data with an insertion? Try
memorizing the following variation, and see how long it takes to
recall it while looking away from this page:
O
beautiful, for spacious skies
For amber
waves of tasty grain
This
task is extremely easy. We have no problem inserting an item in the
middle of something we have memorized. Similarly, if you (like most
Americans) have memorized the famous line “we hold these truths to
be self-evident: that all men are created equal,” then it is very
easy to change that memory into something a little different, such
as: “we hold these truths to be self-evident: that all men are
created pretty much equal.”
So
evidently humans can remember sequences, and it is quite easy for us
to make an insertion anywhere in the sequence. But from a
neurological standpoint, such a thing should be impossible. For let
us imagine that there is some sequence of neurons that stores a
sequential memory, ignoring the difficulty that a neuron has no
“next” and so neurons do not seem to be suitable for storing a sequence. Then let us
imagine we are inserting an item somewhere in the middle of this
sequence. This should be as physically difficult as inserting a new
steel link in the middle of a steel chain (or in the middle of a
chain link fence). We cannot imagine that a new neuron gets created
(in the middle of the sequence) to store the new word or words that
are being inserted, because new neurons are not created for each new item inserted into our memories.
There
is still one other problem in postulating that sequential memory is
stored in the brain. This is the “end of sequence” problem. Try
recalling the song “America the beautiful.” Typically your recall
will end nice and neatly with the line “From sea to shining sea.”
When we remember a sequence of items such as the words in a song, we
remember only up until the end point of the sequence. But how could
we possibly do that, if memories are stored in neurons? Given the
organization of neurons in the brain, storing a memory in neurons
would seem to be like tossing a bucket of letter blocks on to a
mountainous heap of blocks containing letters, words and image
fragments – not at all an arrangement that allows you to tell where
the end point of a particular sequential memory is to be found. Or if
we imagine instead an analogy of writing on a few vines in a thick
Amazon-type jungle of very densely packed vines, the “end of
sequence” problem still is there.
In
short, if long-term memory were stored in the brain, it seems we
shouldn't be able to remember long sequential memories, we should not
be able to remember where such sequences end, and we shouldn't be
able to easily insert new items anywhere in such a sequence – all
things we are actually very capable of doing.
The
points discussed here constitute another argument for believing that
our long-term memories are not actually stored in the brain, but are
stored in some greater mental reality that is merely related to the
brain. An old-fashioned word for such a reality is “soul,”
although it may be just as appropriate to use some other term. The
argument discussed here is only one basis for postulating such a
reality. Another argument is the reason discussed here: given the
rapid molecular turnover in the brain (under which molecules are
replaced every few weeks), there is no plausible and well-founded
explanation for how the brain can be storing very long-term
memories such as memories that last for 50 years. So we have very
good reason for thinking that human memory involves something much
more than just the brain.
There are many anomalies
suggesting a similar conclusion, such as this astonishing account of
a woman with only half a brain. It seems she can instantly state the
day of week of any date you select in the past 18 years, without
using any calculation. She also plays computer solitaire unusually
fast. Such an anomaly is reminiscent of the research of John Lorber,
who found many cases of almost normal functionality in people who had
lost large fractions of their brains due to disease.
In
the field of cosmology, scientists have long recognized that the
known (regular matter and regular energy) is completely inadequate to
account for the behavior of galaxies. So cosmologists have resorted
to saying that there are completely mysterious things that play a
large role in galactic dynamics: dark energy and dark matter. No one
has any idea what these things are. It would seem that when it comes
to explaining the human mind, we are in a rather similar situation.
The reality that we know of (the brain) is quite insufficient to
explain both extraordinary psychic experiences and even the ordinary
reality of human memory. So we need to postulate something more than
just the brain. If we followed the naming convention of the
cosmologists, with their dark matter and dark energy, we might call
this non-biological reality “the dark brain,” which would be a
novel term for an idea that can be described with an old-fashioned
term: a human soul.
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