ICR:No. 200 THINKING ABOUT THE BRAIN by Drs. Don DeYoung and Richard Bliss*

   Introduction

   Whether considering a star or a starfish, design remains one of the
strongest evidences in support of Creation. Opponents never have known
how to deal with the compelling design and plan observed in all parts
of nature.(1) Meanwhile, science accumulates new examples of design
every day. Scripture adds its approval, declaring that there is no
excuse for missing the implications of creative design (Romans 1:20).

   But there is one particular aspect of design which is so powerful,
so convincing, that it almost seems unfair to challenge evolution with
it. The reference is to our brain, the greatest concentration of
chemo-neurological order and complexity in the physical universe. It is
a video camera and library, a computer and communication center, all in
one. And the more the brain is used the better it becomes! A detailed
picture of the human brain is slowly emerging, the origin of which
seems entirely beyond comprehension from a naturalistic point of view.
We see remarkable purpose and interdependence within the brainevery
part works for the benefit of the whole. Such features are not totally
understood; the brain is unable fully to understand itself. As always,
we cannot fully understand the created, intricate details of the
present-day world.

   Description of the Brain

   The adult brain weighs about 1350 grams, just three pounds, yet it
handles the information of 1000 supercomputers. The fundamental unit
within the brain is the neuron, or nerve cell. Each cell, about 10 to
the minus-6th power meter in diameter, contains a nucleus and branching
fibers called dendrites and axons. When a cell "fires," it sends
electro-chemical impulses along its axon extension to neighboring
neurons. These signals, or brain-wave patterns, are in the range of
microvolts. Figure 1 shows two neurons with dendrite-axon contacts
called synapses. Our brain contains about 10 billion neurons (10 to the
10th power). During the first nine months of life, these neurons form
at the astounding rate of 25,000 per minute.
  
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Figure 1. Two neurons are shown, representing the ten billion cells
within the brain. Axons are fibers that interconnect the cells. Axons
are long in motor neurons; the dendrites are long in sensory neurons.
The number of branching dendrites is large and variable.
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   Each neuron is in dendritic contact with perhaps 10,000 other
neurons. The total number of neurological interconnections is on the
order of 10 to the 14th power (100 trillion). This number is equivalent
to all the leaves on all the trees of a vast forest covering half of
the U.S. The total length of the nerve dendrites in an adult brain is
over 100,000 miles!(2) At any given moment the many dendrite
connections can be visualized as light switches that are either on
(firing) or off, controlled by a chemical transmitter. Thus the brain
holds at least 10 to the 14th power bits (binary digits) of
information. Actually, it is a much greater number, since the neurons
also show intermediate firing states, somewhat like a light-dimmer
switch. Consequently, the brain shows both digital and analog
characteristics. At any given moment, perhaps 10% of the brain cells
are firing, at a frequency of about 100 hertz. This implies a rate of
10 to the 15th power signals or computations every second. For
comparison, the Cray-2 supercomputer's speed is 10 to the 9th power
computations per second, with a storage capacity of 10 to the 11 power
bits. Thus, the storage capacity of this supercomputer is 1,000 times
less than that of the human brain. Table I shows the memory capacity of
several systems. Note that the potential brain capacity is estimated as
at least equivalent to that of 25 million volumes, a 500-mile-long
bookshelf! Clearly, the brain is far more advanced than any computer
ever produced. This computer analogy should not be carried too far,
however, because brain organization is unlike anything else encountered
in technology or nature.(3)

   Computer designers have attempted to mimic brain structure with
"neural networks," a type of artificial intelligence (AI). Success has
been very limited; one leader has concluded that some facets of our
thinking will never be duplicated by a machine.(4)

   Table 1. Memory of various systems in terms of words. (One word = 5
bytes = 40 bits, or binary digits.)

   Storage Device Information capacity (words)

   1 typed page 300 3.5" double density compact disk (CD) 40-200 million

   Library of Congress 20 million volumes 2 trillion

   Brain 25 million volumes 2.5 trillion

   Evolutionary Explanations

   A.R. Wallace was a natural historian and an acquaintance of Charles
Darwin. In an exchange of letters in 1869, Wallace wrote, "Natural
selection could only have endowed the savage with a brain a little
superior to that of the ape whereas he possesses one very little
inferior to that of an average member of our learned society." Darwin
realized the threat of this statement to evolution, and replied, "I
hope you have not murdered completely your own and my child."(5) Darwin
feared the death of his evolution theory because the human brain far
exceeded his view of early man. Why did the brain evolve with potential
which never has been utilized to its fullest extent? This "murdered
child" threat greatly troubled Darwin in his later years.(6) Perplexed
by what he observed, Darwin described the brain of even the lowly ant
as the most remarkable speck of matter in the world.(7)

   How does modern secular science explain the assumed "explosive
development" of the human brain? Very creatively! One traditional idea
is that man's discovery of complex tools and speech led to higher
thinking and increased brain size. However, this explanation is a
tautology: Which came first, the increased thinking ability or
increased brain capaity? Today there are new ideas emerging for man's
intelligence, some of them quite humorous. For example, consider the
suggestion that early man had his brain "baked" and damaged by spending
too much time in the hot sun.(8) The brain compensated by evolving
additional neuron connections to make up for the deficit. When our
ancestor finally came in from the sun (or perhaps put on a hat!) his
full brain began to function once again!

   The Two Brains

   One active area of research involves the separate functions of the
brain's left and right hemispheres. These mirror-image halves are
joined together by a massive bundle of perhaps twenty million nerve
fibers called the corpus callosum. The left side of the body is mainly
controlled by the right hemisphere, and vice versa. The left hemisphere
is found to be specialized for language and analytical problem-solving.
The right hemisphere, in contrast, controls visual and artistic ideas.

   A standard secular explanation of this brain division is that the
two hemispheres evolved to provide backup systems for each other in the
event of injury to one side.(9) One might ask, however, why there is
just one division of the brain, when four or six backup parts would
provide even greater survival value. And if the two halves indeed
evolved as backups for each other, then why are they specialized for
different activities? The arbitrary and conflicting ideas of brain
evolution are obvious. Much evolutionary thinking appears to be the
result of dominant right hemisphere activity, where creativity reigns,
and the neglect of the left hemisphere, where logical reasoning occurs!

   Conclusion

   The beautiful complexity of our brain contrasts sharply with all
simplistic secular attempts to explain it away. Our brain remains a
frontier of science; we actually know very little about it, but what is
known is overwhelming. In addition, every single neuronal cell within
the brain contains a trillion atoms. This is like a microscopic
universe within each cell, complete with order, purpose, and
interdependence of components.

   Many topics related to the brain remain for the creationist to
explore: What could our first parents, Adam and Eve, have accomplished
with the possible full use of their brain potential, before the
limitations of the curse? What damage has been done to science by the
false revolutionary idea that brain size is the sole measure of
intelligence?(10)

   The brain truly provides an ultimate design challenge for evolution.
It should be a cause for humble praise in considering the wonder of the
mind. It is a privilege to dedicate these minds to the Creator.

   * Don B. DeYoung, Ph.D., is a Professor of Physics at Grace College,
Winona Lake, Indiana; Richard B. Bliss, Ed.D., is Director of
Curriculum Development at ICR.

   REFERENCES

   1. R. Dawkins, The Blind Watchmaker, Longmans Group, Harlow, Essex
England. 1986, p. 5. 2. M. Denton, Evolution: A Theory in Crisis, Adler
and Adler, Bethesda, Maryland, 1985, p. 330. 3. D. Meredith,
Metamagical Themes, Basic Books, N.Y., 1985. 4. R. Penrose, The
Emperor's New Mind, Oxford University Press, New York, 1989. 5. R.M.
Restak, The Brain the Last Frontier, Doubleday and Company, Inc.,
Garden City, New York, 1979, pp. 58,59. 6. Ibid., p. 67. 7. C.U.M.
Smith, The Brain, G.P. Putnam's Sons, New York, 1970, p. 195. 8. K.R.
Fialkowsky, "A mechanism for the origin of the human brain: a
hypothesis," Current Anthropology 27(6):288, June 1986. See also "A
half-baked theory of how our brains grew?", Discouer 7(9):15, September
1986. 9. R.M. Restak, The Brain, Bantam Books, New York, 1984, p 240.
10. H.B. Sarnat and M.G. Netsky, Evolution of the Nervous System,
Oxford University Press, New York, 1981, p. 398.
