Your Marvelous Brain

For years man’s brain has been likened to a computer, yet recent discoveries show that the comparison falls far short. “How does one begin to comprehend the functioning of an organ with somewhere in the neighborhood of 50 billion neurons with a million billion synapses (connections), and with an overall firing rate of perhaps 10 million billion times per second?” asked Dr. Richard M. Restak. His answer? “The performance of even the most advanced of the neural-network computers . . . has about one ten-thousandth the mental capacity of a housefly.” Consider, then, how much a computer fails to measure up to a human brain, which is so remarkably superior.

What man-made computer can repair itself, rewrite its program, or improve over the years? When a computer system needs to be adjusted, a programmer must write and enter new coded instructions. Our brain does such work automatically, both in the early years of life and in old age. You would not be exaggerating to say that the most advanced computers are very primitive compared to the brain. Scientists have called it “the most complicated structure known” and “the most complex object in the universe.” Consider some discoveries that have led many to conclude that the human brain is the product of a caring Creator.

Use It or Lose It

Useful inventions such as cars and jet planes are basically limited by the fixed mechanisms and electrical systems that men design and install. By contrast, our brain is, at the very least, a highly flexible biological mechanism or system. It can keep changing according to the way it is used—or abused. Two main factors seem responsible for how our brain develops throughout our lifetime—what we allow to enter it through our senses and what we choose to think about.

Although hereditary factors may have a role in mental performance, modern research shows that our brain is not fixed by our genes at the time of conception. “No one suspected that the brain was as changeable as science now knows it to be,” writes Pulitzer prize-winning author Ronald Kotulak. After interviewing more than 300 researchers, he concluded: “The brain is not a static organ; it is a constantly changing mass of cell connections that are deeply affected by experience.”—Inside the Brain.

Still, our experiences are not the only means of shaping our brain. It is affected also by our thinking. Scientists find that the brains of people who remain mentally active have up to 40 percent more connections (synapses) between nerve cells (neurons) than do the brains of the mentally lazy. Neuroscientists conclude: You have to use it or you lose it. What, though, of the elderly? There seems to be some loss of brain cells as a person ages, and advanced age can bring memory loss. Yet the difference is much less than was once believed. A National Geographic report on the human brain said: “Older people . . . retain capacity to generate new connections and to keep old ones via mental activity.”

Recent findings about our brain’s flexibility accord with advice found in the Bible. That book of wisdom urges readers to be ‘transformed by making their mind over’ or to be “made new” through “accurate knowledge” taken into the mind. (Romans 12:2; Colossians 3:10) Jehovah’s Witnesses have seen this happen as people study the Bible and apply its counsel. Many thousands—from the whole spectrum of social and educational backgrounds—have done so. They remain distinct individuals, but they have become happier and more balanced, displaying what a first-century writer called “soundness of mind.” (Acts 26:24, 25) Improvements like these result largely from one’s making good use of a part of the cerebral cortex located in the front of the head.

Your Frontal Lobe

Most neurons in the outer layer of the brain, the cerebral cortex, are not linked directly to muscles and sensory organs. For example, consider the billions of neurons that make up the frontal lobe. (See drawing, page 56.) Brain scans prove that the frontal lobe becomes active when you think of a word or call up memories. The front part of the brain plays a special role in your being you.

“The prefrontal cortex . . . is most involved with elaboration of thought, intelligence, motivation, and personality. It associates experiences necessary for the production of abstract ideas, judgment, persistence, planning, concern for others, and conscience. . . . It is the elaboration of this region that sets human beings apart from other animals.” (Marieb’s Human Anatomy and Physiology) We certainly see evidence of this distinction in what humans have accomplished in fields such as mathematics, philosophy, and justice, which primarily involve the prefrontal cortex.

Why do humans have a large, flexible prefrontal cortex, which contributes to higher mental functions, whereas in animals this area is rudimentary or nonexistent? The contrast is so great that biologists who claim that we evolved speak of the “mysterious explosion in brain size.” Professor of Biology Richard F. Thompson, noting the extraordinary expansion of our cerebral cortex, admits: “As yet we have no very clear understanding of why this happened.” Could the reason lie in man’s having been created with this peerless brain capacity?

Unequaled Communication Skills

Other parts of the brain also contribute to our uniqueness. Behind our prefrontal cortex is a strip stretching across the head—the motor cortex. It contains billions of neurons that connect with our muscles. It too has features that contribute to our being far different from apes or other animals. The primary motor cortex gives us “(1) an exceptional capability to use the hand, the fingers, and the thumb to perform highly dexterous manual tasks, and (2) use of the mouth, lips, tongue, and facial muscles to talk.”—Guyton’s Textbook of Medical Physiology.

Consider briefly how the motor cortex affects your ability to speak. Over half of it is devoted to the organs of communication. This helps to explain the unparalleled communication skills of humans. Though our hands play a role in communication (in writing, normal gestures, or sign language), the mouth usually plays the major part. Human speech—from a baby’s first word to the voice of an elderly person—is unquestionably a marvel. Some 100 muscles in the tongue, lips, jaw, throat, and chest cooperate to produce countless sounds. Note this contrast: One brain cell can direct 2,000 fibers of an athlete’s calf muscle, but brain cells for the voice box may concentrate on only 2 or 3 muscle fibers. Does that not suggest that our brain is specially equipped for communication?

Each short phrase that you utter requires a specific pattern of muscular movements. The meaning of a single expression can change depending upon the degree of movement and split-second timing of scores of different muscles. “At a comfortable rate,” explains speech expert Dr. William H. Perkins, “we utter about 14 sounds per second. That’s twice as fast as we can control our tongue, lips, jaw or any other parts of our speech mechanism when we move them separately. But put them all together for speech and they work the way fingers of expert typists and concert pianists do. Their movements overlap in a symphony of exquisite timing.”

The actual information needed to ask the simple question, “How are you today?” is stored in a part of your brain’s frontal lobe called Broca’s area, which some consider to be your speech center. Nobel laureate neuroscientist Sir John Eccles wrote: “No area corresponding to the . . . speech area of Broca has been recognized in apes.” Even if some similar areas are found in animals, the fact is that scientists cannot get apes to produce more than a few crude speech sounds. You, though, can produce complicated language. To do so, you put words together according to the grammar of your language. Broca’s area helps you do that, both in speaking and in writing.

Of course, you cannot exercise the miracle of speech unless you know at least one language and understand what its words mean. This involves another special part of your brain, known as Wernicke’s area. Here, billions of neurons discern the meaning of spoken or written words. Wernicke’s area helps you to make sense of statements and to comprehend what you hear or read; thus you can learn information and can respond sensibly.

There is even more to your fluent speech. To illustrate: A verbal “Hello” can convey a host of meanings. Your tone of voice reflects whether you are happy, excited, bored, rushed, annoyed, sad, or frightened, and it may even reveal degrees of those emotional states. Another area of your brain supplies information for the emotional part of speech. So, various parts of your brain come into play when you communicate.

Chimpanzees have been taught some limited sign language, but their use of it is essentially limited to simple requests for food or other basics. Having worked to teach chimps simple nonverbal communication, Dr. David Premack concluded: “Human language is an embarrassment for evolutionary theory because it is vastly more powerful than one can account for.”

We might ponder: ‘Why do humans have this marvelous skill to communicate thoughts and feelings, to inquire and to respond?’ The Encyclopedia of Language and Linguistics states that “[human] speech is special” and admits that “the search for precursors in animal communication does not help much in bridging the enormous gap that separates language and speech from nonhuman behaviors.” Professor Ludwig Koehler summarized the difference: “Human speech is a secret; it is a divine gift, a miracle.”

What a difference there is between an ape’s use of signs and the complex language ability of children! Sir John Eccles referred to what most of us have also observed, an ability “exhibited even by 3-year-old children with their torrent of questions in their desire to understand their world.” He added: “By contrast, apes do not ask questions.” Yes, only humans form questions, including questions about the meaning of life.

Memory and More!

When you glance in a mirror, you may think of how you looked when you were younger, even comparing that with what your appearance could be in the years to come or how you would look after applying cosmetics. These thoughts can arise almost unconsciously, yet something very special is occurring, something that no animal can experience.

Unlike animals, who mainly live and act on present needs, humans can contemplate the past and plan for the future. A key to your doing that is the brain’s almost limitless memory capacity. True, animals have a degree of memory, and thus they can find their way back home or recall where food may be. Human memory is far greater. One scientist estimated that our brain can hold information that “would fill some twenty million volumes, as many as in the world’s largest libraries.” Some neuroscientists estimate that during an average life span, a person uses only 1/100 of 1 percent (.0001) of his potential brain capacity. You might well ask, ‘Why do we have a brain with so much capacity that we hardly test a fraction of it in a normal lifetime?’

Nor is our brain just some vast storage place for information, like a supercomputer. Biology professors Robert Ornstein and Richard F. Thompson wrote: “The ability of the human mind to learn—to store and recall information—is the most remarkable phenomenon in the biological universe. Everything that makes us human—language, thought, knowledge, culture—is the result of this extraordinary capability.”

Moreover, you have a conscious mind. That statement may seem basic, but it sums up something that unquestionably makes you exceptional. The mind has been described as “the elusive entity where intelligence, decision making, perception, awareness and sense of self reside.” As creeks, streams, and rivers feed into a sea, so memories, thoughts, images, sounds, and feelings flow constantly into or through our mind. Consciousness, says one definition, is “the perception of what passes in a man’s own mind.”

Modern researchers have made great strides in understanding the physical makeup of the brain and some of the electrochemical processes that occur in it. They can also explain the circuitry and functioning of an advanced computer. However, there is a vast difference between brain and computer. With your brain you are conscious and are aware of your being, but a computer certainly is not. Why the difference?

Frankly, how and why consciousness arises from physical processes in our brain is a mystery. “I don’t see how any science can explain that,” one neurobiologist commented. Also, Professor James Trefil observed: “What, exactly, it means for a human being to be conscious . . . is the only major question in the sciences that we don’t even know how to ask.” One reason why is that scientists are using the brain to try to understand the brain. And just studying the physiology of the brain may not be enough. Consciousness is “one of the most profound mysteries of existence,” observed Dr. David Chalmers, “but knowledge of the brain alone may not get [scientists] to the bottom of it.”

Nonetheless, each of us experiences consciousness. For example, our vivid memories of past events are not mere stored facts, like computer bits of information. We can reflect on our experiences, draw lessons from them, and use them to shape our future. We are able to consider several future scenarios and evaluate the possible effects of each. We have the capacity to analyze, create, appreciate, and love. We can enjoy pleasant conversations about the past, present, and future. We have ethical values about behavior and can use them in making decisions that may or may not be of immediate benefit. We are attracted to beauty in art and morals. In our mind we can mold and refine our ideas and guess how other people will react if we carry these out.

Such factors produce an awareness that sets humans apart from other life-forms on earth. A dog, a cat, or a bird looks in a mirror and responds as if seeing another of its kind. But when you look in a mirror, you are conscious of yourself as a being with the capacities just mentioned. You can reflect on dilemmas, such as: ‘Why do some turtles live 150 years and some trees live over 1,000 years, but an intelligent human makes the news if he reaches 100?’ Dr. Richard Restak states: “The human brain, and the human brain alone, has the capacity to step back, survey its own operation, and thus achieve some degree of transcendence. Indeed, our capacity for rewriting our own script and redefining ourselves in the world is what distinguishes us from all other creatures in the world.”

Man’s consciousness baffles some. The book Life Ascending, while favoring a mere biological explanation, admits: “When we ask how a process [evolution] that resembles a game of chance, with dreadful penalties for the losers, could have generated such qualities as love of beauty and truth, compassion, freedom, and, above all, the expansiveness of the human spirit, we are perplexed. The more we ponder our spiritual resources, the more our wonder deepens.” Very true. Thus, we might round out our view of human uniqueness by a few evidences of our consciousness that illustrate why many are convinced that there must be an intelligent Designer, a Creator, who cares for us.

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From Particle Physics to Your Brain

Professor Paul Davies reflected on the ability of the brain to handle the abstract field of mathematics. “Mathematics is not something that you find lying around in your back yard. It’s produced by the human mind. Yet if we ask where mathematics works best, it is in areas like particle physics and astrophysics, areas of fundamental science that are very, very far removed from everyday affairs.” What does that imply? “It suggests to me that consciousness and our ability to do mathematics are no mere accident, no trivial detail, no insignificant by-product of evolution.”—Are We Alone?