Understanding Brain Chemistry
What is it that makes us human? Is it our actions, our sense of purpose, or our ability to keep our mind on as well as perform complex tasks? Is it that we analyze our own mental processes, as well as the processes of others? What exactly is a mental state, and what creates it? Is it a level of attentiveness, an impulse, or an emotional state? What is it that allows us to experience these things? The answers all lie within our brains.
The brain, like the rest of the nervous system, is composed by and large of neuralgia (glial cells), nerve cells (neurons), that are immersed in a constant flow of cerebrospinal fluid. The glial cells far outnumber the neurons, but have no axons or synapses, and therefore do not play a part in the electrical activity of the brain. They are simpler looking, much smaller, and have lower metabolic rates than neurons.
Another important difference includes that glial cells maintain the ability to recover from an injury and divide their entire lives. Virchow first identified these cells in 1846, and gave them the name “neurogila”, which means nerve glue. Glial cells are credited with holding the brain together, and preserving its physical structure. They are also said to provide both chemical and electric insulation for synapses, as well as the other components of the brain, and transportation for chemicals between neurons and capillaries. Finally, glial cells are thought to break down and/or synthesize the neurotransmitters released by the neurons they shelter. Many mental illnesses are mainly caused by disorders relating to the metabolism of neurotransmitters.
Neurons are the cells that create brain activity, passing chemical and electric signals from one to another. Neurons come in a vast variety of shapes and sizes, but all have branches that fall into one of two categories: dendrites (receptors) and axons (transmitters). Neurons intercommunicate through a synaptic cleft, which is the minuscule gap where an axon from one cell transmits impulses, by the use of neurotransmitters, to the dendrite or cell surface of another neuron. These synapses fall into the three categories, which include excitatory, inhibitory, and modulatory. A healthy human is born with about ten thousand million neurons. These neurons will be connected with up to ten thousand other neurons; receiving rapid pulses from a connected cell’s axon through its own dendrite will activate a cell. When the cell is stimulated, its axon will conduct signals away from the cell using neurotransmitters, and creating a chain reaction. The signal a neuron transmits can be altered slightly, because the cell has the ability to respond to stimuli at strengths different than how it was received. Additionally, the effects of a neurotransmitter is dependant on what type of neuron and dendrite it comes into contact with, as opposed to merely following its “normal” chemical nature. For this reason, it is...