Neurotransmission

Neurotransmission describes organic communication in the brain.  It's the nuts and bolts of message transmission without consideration specifically of the content of messages.  Broca outlined the different areas of the brain in a geographical way depicting how different parts seemed to primarily be important to some task.  Hence the understanding of visual images occurs in the occipital region (backyard)  of the brain.  The sensory mechanism called the eye, has cones and rods which are affected by the light much the same way 'developing paper' and later digital cameras worked.  This information recorded in light and darkness as 'digital' (0100010111) kind of information is then transmitted to the processing part of the brain in the occipatal region, wich Broca gave a distinct number to.
Transmission of information occurred across nerves which by connected by synapses.  Synapses were spaces where chemicals were released which in turn excited another nerve in the relay system of communication.  Further synapses from other nerves could alter the communication speed or even over ride the actual communication.  Neurochemical transmitters were identifed and named such as adrenaline, serotonin, gaba etc.  Some 50 plus neurotransmitters have been discovered.  Different synapses have been identified as well.  Further the brain geographically is not so neatly demarcated as once understood.  The complexity of different broca areas is competing daily with the increasing discoveries of specific roles for different regions.  It's not that there isn't a sensory 'homongus' or little man shaped outline in the brain which is like the whole of the skin surface of our body ,but rather that the sensory communication associated with the homungus can be modified by many other areas of the brain. This is in actual fibers of communication within the brain called 'tracts' . These are rather like 'freeways' while in additon there are back roads and trails of communication between all the different parts of the brain.
The amygdalla is important in emotional modification of messages as the hippocampus is important to memory. These 'solid' structures are however at best 'relay stations' and 'command posts' for the specific functions.  The information about the importance of these 'regions' was first noted with exquisite contribution of surgical genius's like the Canadian neurosurgeon Penfold.  In his surgical attempts to stop epilepsy he noted the relative importance of different parts of the brain.  Further knowledge came from the study of the pathology of brains where a known deficit was identified while the person lived.  Today research is more often delineated with the use of imaging devices such as EEG, CTScan and MRI.  Actual function can be observed with the functional MRI or fMRI.  Further SPECT and PET scan add to the overall picture which to date is vastly limitted by the small numbers in the samples.  Specific questions therefore are easier to answer than any generalized or overall question per se.
This leaves areas of central importance to function connected by multiple hard tracks fueled by chemical communication.  In addition to this the 'hard' brain surrounds a 'lake system' , fluid filled caverns called 'ventricles'.  The Cerebral Spinal Fluid is a veritable soup of nutrients and communication altering chemicals.  Brain cells specifically utilize 'glucose' or 'sugar' which allows alot of the understanding derived from imaging techniques.  By tagging 'sugar' so it can be 'seen' in the functional imaging techniques areas of brain which are working (ie using up sugar) will light up on the camera lens of say the fMRI.  By this technique it was noted that cocaine affected the frontal lobe of the brain and that after cocaine was stopped the frontal lobes of the brain did not return to normal functioning for at least three months.  The frontal lobes of the brain are the youngest developmental regions of the brain and most associated with what is considered to be truly 'human' characteristics such as 'compassion'.  Psychopaths are noted to have the most abnormalities in their frontal lobes compared to normals.
That said, the 'hard' brain rests in this 'soup' of neurotransmitters and chemicals which can modify communications "up and down regulating' it in the jargon of this field of research.  The 'blood brain' barrier can further alter what enters the Cerebral Spinal Fluid.  The blood brain barrier in this sense acts like the 'placenta' for a mother and baby separating what body and brain experience from, say, digestive nutrients.  Hence, the 'vitamins' or 'health food' which is ingested and must then be absorbed from the digestive tract into the body per se must then be further selected for transmission across the blood brain barrier. This transmission is an active membraine whose transmission portals are affected by the homeland security muscled by ATP, a chemical that alters the shape of gateways.
The understanding of neurotransmission with it's balkanization of geographical regions, connected in regular warrens by trails and freeways coupled to  reservoir lakes feeding  the soup of psychoactive chemicals that bathe it, depending on the fickleness of the blood brain barrier,   tends to defy the reductionism that the stupid and lazy firing on even fewer cylinders demand.
Pseudoscience however is always available to give warm and fuzzy answers that ignore the trillions of synapses that make neurotransmission within each brain a microcosm for communication amidst the millions of participants of the earth,who are situated around several lakes and bathed by the atmosphere in chemically active compounds, the least of which is oxygen.
Scientifically then we are like the greatest computer of the Hitchhiker's Guide to the Galaxy which when asked the 'meaning of life' after years spewed out a list of numbers. The understanding of the numbers then begat the building of an even greater computer to decipher the meaning of that code.
Neurotransmission is the way the brain produces a digital series.  Mario de Beauregaard , the brilliant neuroscientist and researcher and author, explains in Spiritual Brain how this 'digital communication' is not as some simplistic souls would have us believe, either mind or soul. Neurotransmission is a function of the brain.  Mind and soul are more akin to the person who sits at this magnificent organic wonder of nature and either programs or deciphers the programs that are possible within the limits of these seemingly limitless matrix.
Is it any wonder that I feel daily as a child of 2 given a space craft before I can read and write and not even knowing if any instruction manual can appreciate the miracle of the sensory apparatus, let alone the world wonderland that I'm allowed to play in, despite all the bullies and dangers that abound.   Neurotransmission then is the internal brain communication, or script that I write a poem with..  It is the words and sentences, maybe even paragraphs and stories but not Shakespeare.  And I am not Shakespeare.  The wonder also is in the uniqueness that abounds, to the eternal frustration of those who would simplistically bar code humans, because of some as yet not understood flaw in the connection between their frontal lobes and heart which makes them blind to what their occipital lobes would tell them about what their eyes can so obviously see.