My knowledge
of quantum physics is pretty weak. All
my training is in biomedical engineering, not physics. When I learned about electrons, it was to use them, not understand them! But in my
old age I’ve tried to learn a bit more about that area of physics. I’ve listened to courses on quantum mechanics
and read some books. Well, it’s not
working! All I figured out is that
physicists get to come up with some pretty strange names: quarks…gluons…charms.…those nerds! That would not happen in medicine. In medicine, everything is named in Latin and
even common items are renamed with some obtuse word so that no one understands
it. But, anyway, even the popular press,
in an attempt to understand quantum physics, picked up on the Higgs Boson and
called it the “God particle” – although that latter name is certainly not
something a physicist would come up with.
Well, this
morning I want to suggest that the real “God particle” is not the Higgs Boson;
it is……the neuron. Of course the neuron
is not a particle, it’s a cell. But I
think it is the center of the material universe. I’d like to make the argument, at least, that
everything smaller builds up to the neuron, and everything larger breaks down
to the neuron. How’s that for a
thesis? Well…give me a chance to explain
and then you can throw your darts!
I mentioned
the neuron in one of my first entries, because it is such a fascinating
cell. It is a living thing that
transmits communication signals throughout the body. Neurons talk to other neurons, who talk to
other neurons, etc. through a complicated network. If you want to do anything, you can’t do it
unless a neuron – or more correctly a whole set of neurons – fire. By “fire” we mean that the neuron generates
an “action potential”, which is the electrical wave that is transmitted along the
neuron, encoding information. A very
interesting and important principle of neuron firing is that it is “all or
none.” This means that the neuron can
have only two states. It is either quiet
(not transmitting signals), or it is firing an action potential. There is no such thing as a “half” action
potential. If you exert a more intense
effort, it isn’t because the action potential in each neuron is bigger. Intensity occurs when neurons fire more
rapidly (more action potentials) or when more neurons fire, or both. This “all or none” principle regarding the
action potential is very important to my basic thesis about the centrality of
the neuron.
It is fundamental
physiology that every movement you make results directly from neurons
firing. Muscles contract because an
action potential travels down the neuron to the neuromuscular junction to the
muscle fibers, causing them to contract.
When you make a movement, it can all be traced to the firing of specific
neurons. Cause and effect. The same is true with sensations – neurons
fire as a result of some sensory input, and the signal is transmitted to the
brain, where more neurons fire and make it into your conscious perception. If I could block the action potentials in all
the neurons in your hand, you won’t feel anything when you touch a hot
stove. If I block all the action
potentials to the muscles in your body, you won’t be able to move. That is very basic neurophysiology.
OK, simple
enough. Let me stop there for a moment
and consider the central role the neuron plays in movement and sensation. It comes down to the action potential, and
the fact that it is “all or none.” First
let me use a sports analogy. At the end
of most games, you either win or lose. A
“1” is placed in the win column or a “1” is placed in the loss column. Ultimately, there is usually a championship
game, and the winner of that game is the champion. That individual or team is 100% “the
champion” and everyone else is 0% “the champion.” As far as the status of “champion” goes,
nothing else with respect to the details of the championship game or any other
games matters. There were lots of things
that would have happened during a season.
If we’re talking about baseball, then every game would have had a few
hundred pitches. There would be clutch
hits and great catches and a myriad of other plays in between, but in the end,
if you ask “were you the champion?”, the answer is either yes or no. [I live in Cleveland – so the answer is no.]
How does that
apply to the neuron? I want to make the
point that lots of things go on “in the background” that result in a neuron
firing an action potential. Molecules
interact with other molecules. Proteins
unfold and fold up again. Ions bounce
around in a seemingly random path, occasionally travelling in and out of the
cell. Electrons move from one place to
another. And if you dig deeper, I guess
you will find quarks doing their things and maybe strings playing tunes and
maybe even “uncertainty principles” playing dice…and on and on. My point is this: everything from the
molecule on down culminates in either one of two states for the neuron: either an action potential fires (“1”) or it
does not (“0”). If an action potential
fires, it travels down the axon to the next neuron, and that next neuron has no
idea whether the first neuron experienced the movement of 1 electron or a
billion electrons in order to make it fire.
All the next neuron knows is either “1” or “0”.
One more step
back. If every action in the universe is
the result of previous actions, one thing people muse about is this: if I knew the state of every atom in the
universe, could I predict what would happen next? Well, with respect to the movement of every
living thing that has a nervous system, I don’t need to know anything about
molecules. If you tell me the firing
status of every neuron, I can predict the movement (ok, yes, technically I can
only predict muscle contraction – actual movement depends on additional
factors). That’s why I say everything
sums up to the neuron. And going from
the top down, I can break a movement down into the individual muscle
contractions, and then to the individual muscle fibers, and ultimately to the
neurons firing. So, therefore, I say
that the firing of the neuron is the “center of the universe” when it comes to
movements.
Next I’m
going to make a leap in logic that I will probably need to come back to at some
point. The leap is this: consciousness, thinking, deciding, etc. share
the same “neuron is central” property that movement does. When we are awake and aware, we experience
ourselves as ourselves. We can think and
decide. We can daydream. If those things are real, then they somehow
represent the firing of neurons in the brain.
As I say elsewhere: if a neuron
doesn’t fire, does it happen? There is
no thinking without neurons firing.
There is no consciousness without neurons firing. When all your neurons stop firing, you are
dead.
In summary, every
sensation, every movement, every thought, every decision…boils down to the
firing of the neuron. And, with respect
to all the things that make us uniquely human, those things are based on
neurons firing and it is not necessary to know what goes on “below” that.
I told all
that to tell you this: if my assertion
is true; and if there is such a thing as free will, then free will happens at the level of
the neuron.
And with
that, I will leave you to your own thoughts - let those neurons fire away!
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