Anatomy: The Human Brain Part 2
The brain is encased in the skull by 22 bones. There are at least 20,000,000,000 neurons in the neo-cortex section (no one has completed counting them) which are held together by 80,000,000,000 or more (glial) glue cells. Electrical-chemical messages travel 1000 times per second across the synaptic gaps (chemical bridges between brain neurons). Each neuron has between 100 and 10,000 synaptic connections. The brain has the ability to store up to 1000 new bits of information per second. Using these figures we find that if we could process and record to memory at that rate, it would take more than 300 years to fill all the neuron spaces available.
If the neo-cortex section of the brain were spread out it would cover 400 square inches of surface area. The neo-cortex burns 400 kilocalories every day. This part of the brain is only a small portion of the total volume yet it contains 70 to 85% of all neurons and controls all higher mental functions
The entire brain consists of three main parts: the reptilian brain, the limbic brain and the neo-cortex, neo-mammalian or intellectual/creative brain.
The reptilian brain is the oldest of the evolutionary brain systems. It was the first to develop and although millions of years old, it’s basically the same in humans as it was in early reptiles or dinosaurs. The reptilian brain deals with the outer environmental and material world, is unemotional, territorial, food and sexually driven and highly motivated towards physical survival. In humans its developmental stage is between conception and approximately 15 months of age. The physical and biological functions of the body are interfaced with other parts of the brain but under the control of the reptilian section. The reptilian brain coordinates wakefulness, self-defense and maintenance of the organism.
In the human species the reptilian brain dominates thought concerning hunting, foraging, organizing the home (in the reptile this is known as selecting a nesting site), mating, establishing boundaries to eliminate outsiders (building fences) and to conform to social hierarchies. The reptilian brain has no, or very few, functional parts for care or concern of offspring.
The typical behavior patterns of the reptilian brain are ritualistic, considers routines very important and also characteristically displays aggressive behavior with bluffing and threats designed to intimidate or instill fear in others. Challenges for territorial rights are met with “I dare you” or “ I am” attitudes. The gestures and body movements of this brain section are choppy and angular when under stress with hips forward and puffing up of the body in an effort to appear as large as possible, like dogs when they walk stiff-legged with their hackles up. Have you ever been so scared your hair stood on end? That’s a reaction of the reptilian brain.
Reptiles and humans who dwell in their reptilian brain, are unemotional, cold towards others and detached from the world around them. They are slow to learn and balk at picking up new information, preferring to “stay the way I am” and to hold on to things even when they are no longer needed. Holding on is an attitude that drains ones life energies. This brain section isn’t capable of innovation, risk taking, transfer of ideas “I already know everything I need to know”, has no ability for reasoning and once a basic pattern is set, becomes stuck in one mode of thinking (high or low gear).
The reptilian part occupies the center of the brain and is directly connected to the spinal cord. It has no capacity for reasoning or innovation. Although there is the ability to memorize or imitate, there is no ability to recognize similarities. This is part of the brain we dwell in when we’re in the victim and victimizer mode or the “why are they doing this to me again?” mentality.
This part of the brain only responds to outside stimuli and is unable to generate its own reality. The reptilian brain has no functional barrier and can’t delay responses to outer stimuli, meaning everything is a knee-jerk reaction. The functional barrier doesn’t develop in humans until about the age of 7. When we consider the behavior patterns connected with this part of the brain we can agree with the scientists who contend that some people never do develop the functional barrier.
Tags: Anatomy , Human Brain , Intelligence , Brain
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