When the surgeon removed a 2in wide, 2in long, and 4in deep section from the top left side of my brain due to cancer, I could hardly raise I right arm. The section removed is called the "pre-motor strip."
Back to the cup of coffee…. As I began to re-train my brain, I noticed how many steps are involved in what, up till then, I assumed was a simple task. First, part of your brain has to decide that you want a drink. Maybe it received a signal from the part of the brain that interprets smells… which intern connects with your memory… childhood memories of smelling coffee roasting at the nearby coffee processing factory are mine. Or maybe it was a signal from our stomach says: “I’m empty”. There are hundreds of other signals and memories that might trigger your brain to say: “I want a drink of coffee.” That, my friends, is just Step 1!
You have decided to take a drink of coffee. That decision sets off a second string of events. The part of the brain that decided to take a drink must issue orders to the part of the brain that controls the muscles in your arm and hand. Guess what? Those orders do not go directly to the appropriate muscles control center. They are passed along by the pre-motor strip!!!! (Read above). And the order is not simply to “Pick up the cup.” It is very complex: What muscles do I need use? How do I hold the cup? (by the handle and by wrapping fingers around the mug?) How firmly do I need to hold it? How far do I need to extend my arm to get the cup? Where is my mouth? How much force do I need to apply to raise said cup to my mouth? This is only part of Step 2.
Now, damage or remove the pre-motor strip!
Your frontal lobe (with input from various other parts of the brain) makes the decisions and issues the orders to take a drink of coffee, but nothing happens. In frustration, you try to make it happen by thinking harder, but nothing happens. However, over the next few days, your brain relearns and you are able to do Step 2 at least semi correctly.
Ok, you have the cup in your hand. You are still learning how to get the coffee to your mouth without spilling it in your lap, but each day you are improving. You have even re-mastered the art of halting the cup a fraction of an inch from your month so that the area right above your upper lip and front of our nose can send a signal to your brain about the coffee’s temperature. Your brain issues new orders to proceed and you take a drink. You have successfully completed Step 3.
But wait. You are not finished yet. The cup is still in your mouth. Similar to Step 1, various parts of the brain are involved in the decision that you have had enough. And as in Step 2, the brain issues orders to lower the cup. All of these sub-steps form Step 4.
At about the time you get the cup down onto the hospital’s beside table, someone comes in: Maybe a friend, maybe a family member, or, if you are really lucky, maybe your doctor, :lol:. You talk for a while and forget that what used to be an order your brain issued to your hand without you hardly noticing it, did not get through: “Let go of the cup, dummy!!!” Letting gravity have its way, you allow your arm to drop onto the bed… cup still firmly in your hand but with hot coffee on your lap.
Step 5: “Let go of the cup, dummy!!!” :lol:
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