The brain is an amazing organ, a one-of-a-kind instrument, a magnificent work of art. If you doubt it, just look at how it’s protected: a bony skull, liquid cushion, and multiple selective membranes all combine to prevent anything from damaging our Central Command Center. We may risk our other body parts for a good cause, but brains we can’t do without. Our brains are Fort Knox. We can’t live without them.
So, what goes on in our brains anyway?
The brain doesn’t work by magic: (poof) an idea! (poof) a thought! (poof) an emotion! It works by electricity … and chemistry. Most of the brain is made of white matter. Here, electrical signals are sent along nerve cell axons until they reach the terminal where the electrical signal is converted to a chemical signal (as a neurotransmitter) to travel across the space between neurons known as the synapse. The post synaptic neuron receives inputs from lots of different neurons. The cell body of the post synaptic neuron does the math, (adds and subtracts inputs) and then, if there is sufficient total stimulus, it activates the signal anew along its own axon in the communication pathway.
Important: there is no decision-making here and no preference shown. That is, there is no, I prefer this impulse to that one, this “thought” to that one. It is all addition and subtraction. These neural expressways don’t decode, decide, alter, alert, or choose; they simply relay. Very democratic. Along the way, the neurons simply communicate the information coded as electrical signals. Mathematically, it is either yes or no. Fire or don’t fire. It is that simple.
So, how do we think, feel or decide?
Most of the brain is made up of “white matter,” nerve cells which appear white because their long axons are wrapped by a protein called myelin which speeds the signal along the length of the nerve cell. Integration of signal information happens in regions of “gray matter” — in the brain periphery and in specialized centers — where many inputs are received and related to previous inputs, experiences and memories and a “decision” is made about responding. It is in the gray matter that we “think.”
Different regions of gray have their own specialized responsibilities and receive and integrate their own specialized kinds of information (i.e. the visual center receives visual input and makes visual associations; the motor center receives input from joints and muscles and associates with motor patterns). Each contributes its assessment to other areas for higher order processing and appropriate response. (i.e. I see that. It looks, sounds and smells like a lion. It’s a lion! It may eat me. I scream and run!) Ironically, if I have never seen a lion, do not know it is dangerous, and it is not acting in a threatening way, I may respond very differently. (i.e. Here kitty, kitty.)
In many ways our brains are just a reflection of us: what we have done, what we are doing, and what we’re planning to do. We are inputting and outputting over our whole life time. It’s all just a matter of coding, comparing and simple calculating. Our brain is the world’s most complex computing device, with one exception: It is ALIVE.
What does it mean for the brain to “be alive”?
Living things are always changing: that is, as they engage with their environment, they adapt and respond. The brain is very much alive. Subjected to various inputs, it adapts and then responds accordingly. Structurally and functionally, it becomes more “sensitive” to input it “knows” and less sensitive or less familiar with input it “doesn’t know.” In this way, brain pathways grow or shrink, strengthen or weaken, speed or slow. They “learn.”
Important: Our brains follow the use-it-or-lose-it principle. The parts we use the most get fortified (see: How exercise makes us smarter) with stronger signals and increased neural traffic; the parts we use less get pruned and send weaker signals and channel less traffic. Because of this, a manageable brain challenge or stress is good for us. It develops stronger and more resilient mental processing and grows a healthier mentality.
Bottom line: how we use our brains effects how they develop and function. (This is what launched the No Child Left Behind program) How we treat our brains impacts how they perform. Just as “we are what we eat,” in very many ways, “we become what we think.”
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