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After reading and rereading about neurons (or nerve cells), we end with this…

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Diagram of a neuron

   A neuron looks like a fried egg with a tail

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   They’re small. 100,000 of them could occupy a volume the size of a grain of sand.

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For a bit more use the DOOR.

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[MORE]

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    Examining several sources¹, here are a dozen facts about neurons. Forgive us if we oversimplify; the comparisons are our own:

   (1)  100,000,000,000 (or 100 billion) neurons are found in the human brain².

   (2)  That means there are are 14 neurons in your brain for every person living on Earth.

   (3)  Neurons have 3 main parts: the soma (the bulbous area with the nucleus) that receives or creates electrical charges, the axon (or “pipeline”), sometimes thousands of time longer than the soma, that carries the charges to the dendrites (or “tail) at the end; the “hair” of the dendrites then pass the charges along to somas of other neurons.

   (4)  They can send an electrical charge from the nucleus (the “fried egg” above) down through their axon, or tail, to one or more other neurons.

   (5)  A neuron has a fixed charge that can be sent down its axon; it totally “fires” or doesn’t fire at all; therefore, a “strong” charge of a neuron is many “firings” over a given period while the fewer firings of another neuron passes on a weaker charge.

   (6)  The “organizing” and firing of electrical charges in our brains determines what we experience from the “outside” through our senses, and how we process that on our “inside” and consequently act or react in thought, word, or deed.

   (7)  Each neuron through its dendrites can form thousands of links to other neurons.

   (8)  It’s estimated that the human brain can have 100,000,000,000,000 (or 100 trillion) links.

   (9)  The human brain weighs about 3 pounds.

   (10)  Human brain cells remain the same throughout life; as a general rule, they don’t replicate themselves.

   (11)  Neuroscientists know the functions of general areas of the brain and many factors that affect them.

   (12)  “Connecting the dots,” so to speak, as to how and why people think and feel as they do still remains a great mystery.

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   As to how human life, or any life, and neurons and brains came about, naturalistic evolutionary scientists believe that all change from very simple molecules to people who can think and talk about molecules came through a series “accidents,” and mutations–some say random events–that occurred over billions of years without supernatural intervention of any kind. In other words, Accidents + Time = Change, with much matter taking increasingly more complex forms.

   Further, some insist that  (“naturalistic”–though that word is usually omitted) “Evolution is fact.”

   Other scientists are uncomfortable with such a dogmatic conclusion when so much about complicated change, and how it occurs, is still unknown.

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   ¹Much of this comes from Wikipedia and other sources on the Internet.

   ² In 2012, Suzana Herculano-Houzel, a Brazilian researcher, concluded through her–interesting but somewhat limited–research that the human brain contained “only” 86,000,000,000 neurons, and that the 100 billion figure had been passed around without solid substantiation. Still, 86 is pretty close to the “100″ that most others use, and besides, it’s easier to handle as we’ve done. Similarly the “7 billion” population reached about 3 years ago is probably on the low side.