©Fernando Caracena 2020
The brain is a computer -like organ of the body that not only controls, regulates. and orchestrates the functions of the other organs of the body, but it is also the central processor of the entire sensory apparatus. It is where our consciousness is located, from where we initiate all willful action. Brain structure and function is an area of active research that has been going on for several hundred years. Like most modern areas of technology, brain research is advancing fast, producing many fascinating discoveries. Most recently neuroscientists have completed the most detailed map of brain function ever. To find out how neuroscientists have explored brain structure and function, look here.
Just as in the other organs of the body, when the tissues of the brain are examined under the microscope,they are found to be made up of cells, in this case called neurons, the fundamental units of the nervous system. A neuron features a long axon, which is up to about a meter in length, through which it communicates electrochemically with other neurons across special, knobby, junction gaps that are called synapses. Neurons are fairly plastic structures forming synaptic connections according to how they are used. In this way they are switching mechanisms that are programmed by what the user chooses to examine and to do. Our life history is written in the synaptic connections that we have inscribed in our brain.
There are neurons that report back sense data to the brain, others that transmit commands to the muscles from the brain, and neurons that communicate specialized portions of the brain with others (2nd ref).
A notable discovery recently made is that neurons are quite sophisticated in function, which is more like the function of what was originally thought to be that of an entire neural network consisting of many neurons. The entire brain is a complex of neurons, which is a network of neurons, each of which is a computer network in its own right. So far we have described two levels of processing. But wait, there is a third level to be described below, which results in a total of three levels of processing, one within the other. That third level also looks like a quantum computer, and in that third level is where some researchers claim that human consciousness resides.
If you do a search of the Web using the phrase, "Where does consciousness reside in the brain?", you will see a lot of explanation that are copies of what some authority figure said that it is an emergent phenomenon. But, if you did deeper you will find that the focus of consciousness is in localized areas of the two hemispheres of the prefrontal cortex. There is where we have left and right brain awareness of past and present. There is where de decide what to do. The rest of the brain handles all the details of how sensory information is presented to our consciousness and how our decisions on how to act are created into and orchestrated into a sequence of motor functions. Our consciousness functions a lot like a king and queen who receive information gathered by many, which is further filtered, presorted, and summarized by others, who conferring among themselves make the decisions that are carried out by their minions.
The picture that I get of brain function [subject to a lot of further research of course] is that data transmitted from the senses is processed in various appropriate areas of the brain that use a variety of computational algorithms to reduce that information into a form, which is to be sent to the seats of consciousness in the prefrontal cortex. Anesthetize those prefrontal cortex areas of the brain and you will have a fully functional brain, but without consciousness. You will have a person that is alive but unconscious.