Our neuroscientists
like to claim that our memories are stored in our brain. There is a
way to test this claim. I will review each of the things that a
computer uses to store and retrieve data, and in each case I will
ask: is there something like that in the brain? I will use pretty
much the simplest example of data storage and retrieval I can think
of: the storage of a small file containing a few words of text. Below
are the things that a computer uses to store and retrieve such
information.
Item
# 1: An Operating System
Besides applications
that do specific things, a computer has what is called an operating
system that does various low-level tasks. Bill Gates originally made
his fortune by selling the MS-DOS operating system that was the first
high-selling operating system used by personal computers. Nowadays if
you have a desktop computer you may be using some Windows operating
system such as Windows 10, or some Apple operating system. An
operating system is a highly complex and coordinated base of code
that serves as a kind of foundation for applications that are built
to leverage that operating system.
As far as we know,
the brain has no such thing as an operating system. There are
particular genes that list the amino acid constituents of particular
brain proteins, but those structural proteins are like hardware,
rather than the software that is an operating system.
Item
# 2: An Application to Store and Retrieve Data
While it is possible
to store a small amount of data on a computer merely using a nerdy
command-line string of characters, almost no one does that to store
text data. Instead, 99% of the time someone will use an application
to store data. An application is a program that does some specific
type of work, typically by leveraging the functionality in the
operating system. A person using a Windows operating system might use
an application program such as Notepad, Wordpad, or Microsoft Word to
store text data.
As far as we know,
the brain has no such thing as application programs. No one has ever
given a coherent description of how storing information to the brain
would involve making use of “how to” instructions stored
elsewhere in the brain, some set of instructions that could be
compared to an application program.
Item
# 3: The ASCII Code for Encoding Information
Text
is never directly written to a file stored on your computer's hard
drive or a zip-drive. If, for example, you were to break apart your
computer's hard drive (or break apart a small zip drive), and look at
its contents in a high-magnification microscope, you would never see
little tiny “a,” “b,” and “c” characters. What actually
happens when your text data is stored is this: (1) the ASCII code is
used to convert each of your text characters into a number; (b) those
numbers are then converted from decimal into binary; (c) the binary
information is then stored on your computer's hard drive or a zip
drive. The ASCII code consists of a table in which each character is
represented by a number.
Does the brain have
anything like this? As far as we know, it does not. The ASCII code is
an example of an encoding protocol, and no one has ever been able to
discover any encoding protocol used by the brain to store
information.
Item
# 4: A Decimal to Binary Conversion Table or Utility
The ASCII code
merely converts letter to decimal numbers, numbers that use the Base
10 system. But computers store information using binary code, and
when binary is used, numbers are stored using the Base 2 system. So
rather than directly writing text represented in the ASCII code, an
application must convert from decimal to binary.
This is another
encoding protocol that does not correspond to any functionality known
to exist in the brain.
Item
# 5: A Medium That Allows a Permanent, Stable Storage of Information
When a computer has
all the bits needed to write, it must have a stable medium to write
to. Some of the earliest stable media to write to were clay (used in
writing cuneiform), parchment, and paper. Nowadays computers use a
stable medium such as magnetic disks.
Does
the brain have anything like this – some medium allowing a
permanent, stable storage of information? It would seem not, at least
nothing that could be used by the brain to store memories that last
for years. The main assumption during the past decades has been that
memories are stored in synapses. But synapses are an unstable
“shifting sands” type of medium subject to high molecular
turnover and structural turnover. As discussed earlier, rapid
molecular turnover in synapses should make them unsuitable for
storing memories that last longer than a year. But humans are able to
remember many memories for 50 years or longer. As a scientific paper
puts it:
Experience-dependent behavioral memories can last a lifetime, whereas even a long-lived protein or mRNA molecule has a half-life of around 24 hrs. Thus, the constituent molecules that subserve the maintenance of a memory will have completely turned over, i.e. have been broken down and resynthesized, over the course of about 1 week.
Experience-dependent behavioral memories can last a lifetime, whereas even a long-lived protein or mRNA molecule has a half-life of around 24 hrs. Thus, the constituent molecules that subserve the maintenance of a memory will have completely turned over, i.e. have been broken down and resynthesized, over the course of about 1 week.
The DNA inside
neurons is a stable medium for permanent information storage, but it
doesn't seem to be used for storing our memories. Our DNA has been
exhaustively studied by projects such as the Human Genome Project and
the Encode project. No one has discovered the memories of any
particular human in that human's DNA.
Shockingly, there
seems to be no plausible candidate for a particular component in the
brain where the brain could be storing memories that last for
decades. Neither synapses nor DNA is such a plausible candidate.
Item
# 6: A Storage Location System by Which the Exact Position of a Data
Item Can be Specified, Allowing Fast Retrieval from an Exact Location
When a computer
stores data on a hard drive or zip file, it's not similar to adding
to a heap, something similar to pouring another cup of water in a
swimming pool full of water. It's always rather like putting some new
papers in a particular file of a filing cabinet. This is so that
information can be retrieved rapidly. You can get papers from a file
in a file cabinet quickly, but it would take you way too long to get
that information if you just had some giant heap of papers in the
middle of your office.
So whenever your
computer stores data, it has some idea of a specific location where
this data will be saved. For example, you may store your little text
data in a file called SaturdayNote.txt in a folder or directory
called MyTextFiles. That gives the computer a way to retrieve this
information quickly, by first going to that particular folder or
directory, and then searching for the file named SaturdayNote.txt
file in that particular folder or directory.
Does the brain have
any type of similar system for storing information in specific named
locations? As far as we know, it does not. It's hard to conceive of
how such a thing could possibly exist in the brain. The brain is more
like a tower-sized ball of tangled spaghetti than some city with
labeled streets. There seems to be no way in which a brain could ever
know exactly where some data was that it was storing. Neurons don't
have any coordinate system allowing anything to tell a precise
location in the brain. If your brain somehow wrote some information
to a brain position of X=2345, Y=24342, Z=73252, there would be no
way for the brain to record that exact position in a way that would
allow that exact location to be quickly accessed. Writing some
information to the brain would seem to be like writing on some index
card, and throwing it into the middle of an Olympic-sized swimming
pool full to the brim with index cards. Under such a setup,
instantaneous retrieval of some precise information should be
impossible.
Item
7: Read/Write Functionality Allowing Data to Be Written to a Specific
Location and Also Read From the Same Location
The discussion under
Item #6 above was purely a discussion of an organizational system in
which some data can be given a location for it to be stored. A
separate requirement is that data can be written to a storage medium,
and also read from that storage medium. The reading and the writing
must occur in a very consistent way, so that the data read is exactly
the same as the data written.
Your computer has
one or more systems capable of such read/write functionality. For
example, a hard disk in a computer is a read-write device. There is
complicated hardware involved. There is a read-write arm which can
move back and forth in a particular line, and also a spinning disk
underneath that arm. At the end of the read-write arm is a read-write
head that can read data when it is above some particular location.
With the combination of these two things, the system can read and
write from any desired location on the disk.
A read-write head of a hard drive
Does the brain have any such read-write functionality? Some think that what is called long-term potentiation acts like a write system for storing memories. But the term long-term potentiation is very misleading. Long-term potentiation (LTP) is actually a very short-lived effect, almost always lasting less than a few weeks. The brain may have some kind of system for writing something that will last a short time, rather comparable to someone writing in the wet beach sand with his fingers. But there is no known write mechanism by which the brain could permanently store data.
When it comes to
read functionality, we know of no mechanism at all for such a thing.
There seems to be absolutely nothing in the brain similar to the
read-write head of a hard disk, something that might allow the brain
to “zoom in” and read from one particular location. A system has
to be organized in a very specific way for read-write functionality
to be possible, and the brain seems to be organized in no such way.
Our neuroscientists
tend to dogmatically speak as if our memories are all stored in
brains, but this is more of an ossified dogma rather than a truth
determined by observations. Neuroscience itself undermines such a
doctrine, by indicating that there is no stable component that the
brain could be using to store memories lasting decades. Comparing the
brain to a computer, we find that the brain has nothing like any of
the 7 main things that the computer uses to store and retrieve data.
But our minds recall obscure information instantly, and a single
phrase may get you to instantly recall some old tune you have not
heard in 50 years (as recently happened to me).
The discussion above
should be very discouraging to anyone who hopes to explain how brains
could achieve the memory capabilities of human minds. To such a
person I must merely say: you're barking up the wrong tree. The feats
of our minds cannot be explained solely in terms of the brain. We
must postulate some psychic or spiritual component to account for the
feats of our minds, something beyond the brain. Such a thing is
needed to account for the wonders of psychic phenomena, and is also
needed to account for the ordinary marvels of the human mind such as
the instantaneous recall of childhood memories.
We may imagine the following conversation between a curious young boy and a distracted mother walking on the street.
Boy: Mommy, who made the clothes I wear? And who made the TV shows I watch? And who made the cars I see? And who made the street lights?
Mother: The answers are simple, my son. They are: Santa Claus, Santa Claus, Santa Claus, and Santa Claus.
We can also imagine a similar conversation between a philosopher and a neuroscientist.
Philosopher: From whence comes that hint of the transcendent we feel when we look at a sky ablaze with stars? From where do our loftiest ethical principles arise? Why do we lie awake and ponder the weightiest riddles of existence? How do we ever grasp the most abstract notions such as the idea of the universe and the eternal laws of nature?
Neuroscientist: The answers are simple. They are: neurons, neurons, neurons, and neurons.
Such simplistic answers are convenient, but should we not suspect such complex questions have equally complex answers?
We may imagine the following conversation between a curious young boy and a distracted mother walking on the street.
Boy: Mommy, who made the clothes I wear? And who made the TV shows I watch? And who made the cars I see? And who made the street lights?
Mother: The answers are simple, my son. They are: Santa Claus, Santa Claus, Santa Claus, and Santa Claus.
We can also imagine a similar conversation between a philosopher and a neuroscientist.
Philosopher: From whence comes that hint of the transcendent we feel when we look at a sky ablaze with stars? From where do our loftiest ethical principles arise? Why do we lie awake and ponder the weightiest riddles of existence? How do we ever grasp the most abstract notions such as the idea of the universe and the eternal laws of nature?
Neuroscientist: The answers are simple. They are: neurons, neurons, neurons, and neurons.
Such simplistic answers are convenient, but should we not suspect such complex questions have equally complex answers?
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