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3
The Third-Person
View of the Mind


Introduction
The third-person view of the mind is from the outside, the
objective world of science and medicine. It is how we are
observed by those around us. The disturbing part is that our
colleagues tell us, "Sorry old chap, but your mind is nothing
but electrochemical activity in three pounds of meat." This is
how science sees consciousness, nothing but the operation of
the human brain. To make this even worse, the method of
reduction tells us that brain activity is pure Information,
something so abstract that it can be transmitted over a
communications channel or stored in a computer memory. The
goal of this chapter is to present the evidence for these stark
conclusions.

A Brief Tour of the Brain
Medicine has a good understanding of the functions carried
out by the body™s various organs. For instance, the heart pumps
blood, the lungs deliver oxygen, and the kidneys extract waste.
But what about the brain, what does medical science view as its
function? The answer is that the brain is needed for movement.
This is one of the fundamental differences between plants and
animals. Since plants do not move, they do not need brains.
Animals are different; their very survival depends on body
movement to capture food, escape enemies, and find mates.
This requires animals to have three specialized systems. First,
they need muscles to actually move their bodies. Second, they
need sensory organs, such as the eyes and ears, to examine their
environment. Third, they need a way of tying the sensory

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24

organs and the muscles together. This is where the brain comes
in. Its function is to receive information about the environment
from the senses, decide how to move the body to achieve
survival and reproduction, and control the muscles to carry out
the planned action. Figure 3-1 illustrates this role of the brain
as the link between the senses and muscles.
Incredible as it may seem, all of these functions are carried
out by a single type of building block, the nerve cell or neuron.
Neurons come in a variety of shapes and sizes depending on
where in the nervous system they are located. However, all
neurons have the same general structure and operate in the same
basic way. As shown in Fig. 3-2, each neuron has a cell body
containing a nucleus and other components needed to keep the
cell alive. Two kinds of projections extend from the cell body,
the dendrites, where the signals enter the neuron, and the axon,
where the signals exit. To allow the signals to jump from one
neuron to the next, the end of each axon is positioned next to
the dendrites of its neighbor, forming a connection called a
synapse.
The neuron has a unique property that allows it to transport
and process information. In the jargon of biology, neurons can
fire. It works like this. The membrane around the neuron is
capable of moving charged particles (ions) into and out of the
cell. This pumping action results in the cell becoming a tiny
battery, with the inside of the cell negative and the outside of
the cell positive. The neuron remains in this condition until
something stimulates one of the dendrites. For example,
neurons in the eye are sensitive to light, and neurons in the ear
are sensitive to sound. Neurons in the brain and spinal cord are
only sensitive to the firing of neighboring nerve cells. When
the dendrites receive sufficient stimulation, the cell membrane
briefly flips its electrical polarity. For about one-thousandth of
a second, the inside of the cell becomes positive and the outside
negative, and then the cell returns to its normal condition. This
brief polarity flip is called an action potential. Once the action
Chapter 3: The Third-Person View of the Mind 25




FIGURE 3-1
The function of the brain. Animals
must move in their environment to
survive and reproduce. This requires
senses to provide information about
where to move, and muscles to carry
out the movement. The function of
the brain is to connect these two.
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26

potential is started at the dendrites it cannot be stopped; it
quickly spreads through the cell body and down the axon. In
less scientific terms, tickling a dendrite causes the nerve cell to
pop, sending a short electrical pulse from one end to the other.
Although the action potential only lasts about one-
thousandth of a second at any particular location in a cell, it can
take much longer to move down a long axon. For instance,
some of the axons in the legs and spinal cord are several feet in
length, and it would normally take nearly a second for the action
potential to move from one end to the other. To overcome this
time delay, most neurons have their axons covered with a fatty
substance called myelin. As shown in Fig. 3-2, the myelin
sheath is interrupted at regular intervals by small breaks called
the nodes of Ranvier. An action potential moves along a
myelinated axon very quickly because it jumps from node-to-
node, rather than traveling in the normal way. This reduces the
transit time by a factor of about one-hundred. For instance, you
have probably stubbed your toe and thought to yourself, "that's
going to hurt." Several seconds later the pain begins. This is
because the neurons in your toe that detect pressure send their
signals to the brain by fast myelinated axons. However,
sensations of pain are conducted along unmyelinated axons,
requiring several seconds to move from your toe to your head.
As another example, you may be familiar with a person stricken
with Multiple Sclerosis, a disease where the myelin degenerates.
The resulting disruption of the neural transmission causes a
variety of problems in sensation and movement.
Now let™s take a closer look at the synapse, the connection
between neurons. This is the most interesting location in the
entire nervous system; it™s where the important things happen.
Except in rare cases, the action potential from one neuron
cannot directly cause the next neuron to fire. This is because
there is an extremely thin space between the axon and dendrite
called the synaptic gap. Instead, the end of each axon contains
small containers of chemicals called synaptic vesicles. When
an action potential reaches the end of an axon, it stimulates
Chapter 3: The Third-Person View of the Mind 27




FIGURE 3-2
The neuron. The nerve cell, also called the neuron, is the basic
building block of the brain and other nervous pathways.
Stimulation of the dendrites cause the neuron to fire, sending a
brief electrical pulse from the dendrites, through the cell body,
and down the axon. This electrical pulse is called an action
potential, and can be transferred from one neuron to the next
through a connection called the synapse.
The Inner Light Theory of Consciousness
28

the synaptic vesicles causing them to release their chemicals
into the synaptic gap. These chemicals move across the gap and
affect the neighboring dendrite in some way, depending on the
particular chemical released. Some encourage the next cell to
fire, while other act to discourage firing. These chemicals
released into the synaptic gap are called neurotransmitters. A
few of the most common ones are called: acetylcholine,
epinephrine, norepinephrine, serotonin, dopamine, and GABA.
Figure 3-3 illustrates this process of an action potential traveling
down an axon, resulting in the release of the neurotransmitter
into the synaptic gap.




FIGURE 3-3
Neurotransmitter release. Action potentials do not jump directly
from one neuron to the next. Instead, when an action potential
reaches the end of the axon, chemicals called neurotransmitters
are released into the synaptic gap. These chemicals then initiate
action potentials in the neighboring neurons.
Chapter 3: The Third-Person View of the Mind 29

To understand how these neural connections account for
human behavior, consider what happens when we greet a friend.
First, light is reflected from our friend's face into our eyes.
After entering our pupils, it is focused onto the back surface of
each eyeball. This is the location of the retina, a layer of
neurons that fire when exposed to light. As an example, a
neuron in the retina might fire 200 times each second when
exposed to bright light, and only five times each second when
in darkness. The axons of about ten-thousand of these neurons
leave the back of each eye to form the optic nerve, carrying the
signals that represent patterns of lightness, darkness, and color
into the brain. The other senses operate in a similar way;
neurons in the ears fire when stimulated by sound, those in the
skin by pressure and temperature, and those in the nose and
mouth by chemical reactions. All of this information is carried
into the brain by action potentials traveling down axons.
After a few seconds, we recognize our friend and respond
by extending our hand to be shaken. This movement is
controlled by neural pathways that start in the brain, lead down
the spinal cord, and terminate in the muscles of the chest and
arms. The force of the muscle contraction is determined by how
fast these nerve cells fire, allowing the brain to control the
movement in a smooth and well-coordinated manner. Most of
the muscles in the body are controlled this way, except a few
that need to operate on their own, such as the heart and
digestive tract. The muscles that produce speech are also
supervised by the brain. When we utter, “Hi Bob, it™s good to
see you,” the muscles in the diaphragm, vocal cords, tongue and
lips, are simply responding to action potentials traveling down
neurons from the brain.
Here is the important point: the only things that go into and
out of the brain are firing patterns of neurons. But this brings
us to the difficult part, to say the least. How does the brain
determine what output to generate in response to a given input?
For instance, how do we recognize the face of our friend, know
what muscles to contract to extend our hand, or how to vocalize
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30

a greeting? Keep in mind that the brain must accomplish these
tasks by using nothing more than cells that fire at different rates.
At first glance, this problem of changing the sensory input into
the muscle output seems overwhelmingly complicated. And
when you look at it longer, it becomes even worse.
How does the brain do it? First, there are an incredible
number of neurons in the brain, roughly 100 billion. Second,
each neuron is connected to a multitude of other neurons (not
just a single one as illustrated in Fig. 3-2). In round numbers,
each neuron in the brain influences about 1,000 of its neighbors,
resulting in an extraordinary 100 trillion synapses. Scientists
call this maze of interconnected nerve cells a neural network.
Third, the pathways in the brain do not just go from the
input to the output, but bend back on themselves to form loops
in the neural network. Figure 3-4 illustrates this operation.
Information from the senses is conducted to the brain where it
joins the already circulating patterns of neural activity.
Likewise, portions of this circulating neural activity break off
and pass to the muscles for body control. Of course, this
diagram is trivial compared to the enormous complexity of the
human brain. For instance, imagine that you tried to count all
of the brain's connections by looking through a high-power
microscope. At a rate of one synapse every second, it would
take more than 100,000 lifetimes to tally the entire brain.
Lastly, there is a fourth general feature of the brain, it is
highly adaptable. Each time a person learns something, be it a
mathematical equation or the face of a new friend, the brain
must change in some way to incorporate this knowledge. In
adults, the primary change in the brain is a modification of the
so-called synaptic weights. As previously described, when a
neuron fires it affects its neighbors through the release of a
neurotransmitter into the synaptic gap. The more neuro-
transmitter is released, the greater the effect on the neighboring
cells, to either encourage or discourage them from firing. The
term synaptic weight refers to how much one neuron™s firing
affects it neighbors.
Chapter 3: The Third-Person View of the Mind 31




FIGURE 3-4
Circulation of neural activity. Patterns of action potentials are
sent from the senses to the brain where they enter the already
circulating patterns of neural activity. Portions of this neural
activity exit the circulation to control the muscles.


Long term memory is accomplished in the brain by
modifying synaptic weights in response to experience. Suppose
you meet a person for the first time and your brain tries to
remember what their face looks like. The signals pass from the
eyes to the brain along the optic nerve, setting up a pattern of
neural activity in the brain that corresponds to the person™s
face. This activity changes the synaptic weights between the
affected neurons, such as by increasing or decreasing the level
of the neurotransmitter that is released when each nerve cell
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32

fires. When you see the person™s face at a later time, it causes
a similar pattern of neural activity. However, this time the
modified neural weights already match the pattern of activity,
a condition that the brain interprets as recognition. Present day
science has a general grasp of how this can occur in neural

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