This is Joe’s Brain
Compared to me, other wonders of the universe pale into insignificance. I am a one and a Half-Kilo mushroom of gray and white tissue of gelatinous consistency. No computer exists that can duplicate all my myriad functions. My component parts are staggering in number: some 30 billion neurons and five to ten times that number of glial cells. And all this fitted into the crown of a size 7 hat! I am Joe’s Brain.
I am not just part of Joe, I am Joe-his personality, his reactions, his mental capacity. He thinks that he hears with his ears, tastes with his tongue, and feels with his fingers. All these things happen inside of me — ears, tongue and fingers merely gather information. I tell him when he is sick, when he is hungry; I govern his sex urge, his moods, everything.Even when he is asleep I continue to handle traffic that would swamp all the world’s telephone exchanges. The amount of information flooding in on Joe from the outside is staggering. How can I cope with it all? I simply select what is important, and Joe ignores the rest. If Joe puts a phonograph record on and attempts to read at the same time, he will concentrate on the record or the book, not both. If Joe becomes involved in a particularly good novel, he should not
be surprised if he does not remember hearing his favorite musical passage.
Of course, if something potentially dangerous happens, I instantly shift gears. Let Joe slip on the ice and I immediately direct him to regain his balance, and then signal his arms to break the fall. Finally, if he hits the ground, I let Joe know if he is hurt. And the event is stored in my memory to warn Joe to walk carefully on ice in the future.
In addition to taking care of such emergencies, I have thousands of housekeeping chores to perform. Overseeing breathing, for example. Sensors inform me that carbon dioxide is rising in Joe’s blood and that he needs more oxygen. I step up the breathing rate – timing the contraction and relaxation of chest muscles. In thousands of such ways I baby Joe In return, I am piggishly demanding. Although I represent only two percent of Joe’s body weight, I require 20 percent of the oxygen he inhales and a fifth of the blood his heart pumps. I am utterly dependent on a constant supply. Let there be a temporary shortage and Joe faints. Let the supply be cut off for a few minutes and I suffer grave damage– paralysis or death may result. I also demand a steady supply of nourishment-glucose. Even in situations of acute starvation, I get first call on any available, for without me Joe would die.
In many respects, I am like a vast, unexplored continent, with little more known than the rough outlines of the shore. But the re searchers who are attempting to map me have come up with some fascinating information. For example, although all pain is felt in me, I myself have no pain sensation even when I am cut. Thus, brain surgery is performed with the patient wide-awake, allowing the brain explorers to stimulate specific areas of me electrically and observe the response. If Joe ever undergoes such surgery, he will be amazed at what can happen. A tickle of electricity in one place and he might”see” a long forgotten third grade teacher. Stimulated in other places, he might “hear” a train whistle or a recitation of nursery rhyme he could not have recalled a few hours earlier. I am like an old attic containing mementos of a lifetime. Joe might not be aware of what it is in the attic, it really is there.The brain mappers have at least a rough outline of my primary functioning areas: vision in the rear, hearing on the sides.
Perhaps the most interesting discovery is the “pleasure center.” Teach a rat to press a switch that gives a minute electrical prod to the “pleasure center” and the animal will press the switch almost continuously– preferring the stimulation even to food, Given time, it could die of starvation-presumably happily. If Joe ever suffers a severe depression, doctors might implant such an electrode in his brain. Little pits of electricity could transform a depressed Joe into an ecstatic Joe.
I reside, of course, in a well-protected fortress. The skull is about half a centimeter thick at the top, and even thicker at the base. I am bathed in a watery fluid that cushions me from shocks. A blood- brain barrier serves as a gatekeeper letting some things in, denying entrance to others. Thus, it welcomes the glucose I need, but blocks out bacteria and toxic substances. Most painkillers and anesthetics pass in with ease, unfortunately, as does alcohol and hallucinogenic drugs that wildly distort my normal activities.
A word about my architecture. Lift a piece of sod from a lawn and note the baffling intertwining of roots. I am something like that –multiplied by millions. Each of my 30 billion nerve cells, or neurons, connects with others — some as many as 64000 times!
A neuron looks something like a spider attached to a filament. The spider is the cell body, the filament the axon, the legs the dendrites. The legs pick up a signal from adjacent neurons, pass it to the body; the signal is in turn passed along by the filament at speeds up to 340 km.p.h. After each signal passes, it takes the filament about 1/2000 of a second to recharge itself chemically. At no point does one of my neurons touch another; signals are passed spark-gap fashion. At each “firing” one nerve chemically communicates with another.
For all my versatility, I unfortunately never learned the wonders of reproduction. Skin liver tissue, blood cells can be replaced after damage or loss. If I lose one of my cells it is lost forever–and by age 35, Joe was losing over 1000 of my nerve cells a day! With age, I also lose weight and for my great reserves , these things might be disastrous. I compensate. Let a thousand cells die and a thousand others may never notice the loss. If enough cells are destroyed, Joe sense of smell might diminish. His taste could become less acute and hearing fade. Joe might notice his attention span diminishing, and he might have more difficulty remembering names, dates, telephone numbers. I will take care of the really important jobs to the end.
Joe knows he has two kidneys, two lungs, two adrenals. He does not think of me as a “paired” organ, in a sense I am, in that I have distinct right and left hemispheres. My left half controls much of the activity on the right side of his body, my other hemisphere the left. With right-handed people, the left hemisphere is dominant. With Lefties, the reverse is true.
Recent studies suggest that my left hemisphere controls Joe’s ability to walk, write and do mathematics. My right hemisphere is essentially mute but can do other things, such as make spatial judgments.
Certainly, though, my most striking feature is my backup system. I store each memory in various places-either the sight of an apple tree or the sound of a brook could trigger the same memory of a special spot in Vermont. Thus, it is possible for Joe to manage quite nicely even with part of me destroyed. My remaining part may require considerable time to take over jobs strange to it. Frequently I am able to set up compensating networks of nerve connections. Speech may return, life may come back to paralyzed limbs, cobwebs clear. I AM JOE’S BRAIN
For more information…”I Am Joe’s Body” by J.D. Radcliff on Amazon.com