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Chapter 9.2

Three Levels of the Brain.

Earthy emotions can be understood by looking at human evolution. Humans descended from a single reptilian ancestor approximately 320 million years ago.

 The human brain was built through evolutionary processes in three stages.  The stages are Reptilian Brain, the Old Mammalian Brain and the Rational Brain.

1 The Reptilian Brain 

The first stage is similar to Reptilian Brain (Basal Ganglia) and it consists of a brain stem and a cerebellum. It is responsible for primitive raw emotions such as paranoia, obsession and compulsion. (It also regulates heart and body temperature.)

The earthy emotion of fear which produces a fight or flight response is an automatic reaction to an event that is perceived as stressful or frightening by the Reptilian Brain. The perception of threat activates the sympathetic nervous system and triggers an acute stress response that prepares the body to fight or flee.

2 The Old Mammalian Brain (Limbic System)

The second stage is similar to the brain of the first mammals.  The Old Mammalian Brain (Limbic System) consists of the hypothalamus, amygdala and the hippocampus. This brain is also known as the Paleomammalian Brain.

This intermediate stage  of brain development is responsible for subconscious emotions such as fear, joy, fighting and sexual behaviour. Some of our instinctive knowledge of right and wrong stems may come from the Old Mammalian Brain.  The old mammalian brain is found in a large percentage of mammals and is believed to have a strong intricate connection with the neocortex.  The Old Mammalian Brain may play a role in a person's judgment of right and wrong. Also it is thought that this brain may malfunction and cause deep distress when there is no stimuli to cause such a response which is seen in Post-Traumatic Stress Disorder.

Fear can be triggered both by the Reptilian Brain or the Old Mammalian Brain. fear which produces a fight or flight response is an automatic reaction to an event that is perceived as stressful or frightening by the Reptilian Brain. The perception of threat activates the sympathetic nervous system and triggers an acute stress response that prepares the body to fight or flee.

 3 The Rational Brain

The Rational Brain is found in higher mammals. It is especially predominate in the human brain, and is not found in birds or reptiles. The Rational Brain is complex. This brain is also known as the Neomammalian Brain, or the Neocortex.

The neocortex is made up of grey matter consisting of folds to increase the surface area and memory retention. The arrangement of these folds differs from human to human, and is believed to account for the differing cognitive abilities of individual humans. Its more primitive functions include motor control, sensory perception and cognition.

An unique feature of the neocortex is the way in which the gray matter is arranged together in columns. In the human brain, the six neocortex layers are 2.5mm thick and contain thousands of different types of cells.  This is one indicator of a hierarchy in the mind.

Emotions Play Out on the Inner Stage
 of the Self

Spiritual and earthy emotions feed into the self.  The self is who we think we are both long term and short term.  Within the self is a stage were we act out our emotions.

By giving thought and selecting spiritual feelings over earthy emotions we become a happier, more optimized and have much better relationships.