It may seem little confusing before understanding the whole anatomy of human brain, to be precise the 3 parts of our brain. There are different structures layered with great craftsmanship inside our brain which in order to understand you shall start with the evolution process that led to the formation of a brain model. Popular neuroscientist Paul D. MacLean first brought the concept of limbic system in front of the world which states that our brain comprises of three brains actually. Paul D. MacLean further discussed the theory in his book The Triune Brain in Evolution that gives a proper understanding of the brain anatomy and its successive evolution.
The three recognized part of brain are:
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Reptilian brain- It connects best with the survival instinct. Made out of the cerebellum and the brain stem, its fundamental duty is to survive and maintain the body. It basically performs the major task like breathing, controlling body movements, reproduction, etc. The reptile brain is similar to that found in a lizard’s brain. Most of the function of this brain is in subconscious state and done automatically, hence it is not changed easily until forced to change. It is the most oldest amongst the 3 parts of our brain. This brain dominates when a person is sleeping or in coma.
Limbic System or Mammalian Brain-It is the second layer as suggested in the anatomy of human brain that comes right after reptile. This part is also regarded as the ‘feeling brain’ as it is concerned with the feelings and emotion of a human being. The limbic brain controls the emotion of the body such as anger, pity, sorrow, at a subconscious level which strongly influences the way of human behavior. Another neuroscientist Jaak Panksepp says "subjective feelings and emotional responses to world events interacting with innate motivational value systems." which means it plays a vital role in social bonding and interaction with other human beings.
Neocortex-It is the outer most part of 3 parts of our brain, hence considered to be evolved after the reptile and mammal brains. Also it comprises a large volume of space in our brain and with the comparatively more number of neurons gives better connectivity to the human body. The basic function of neorocortex is to make the body able to implement basic logic, develop speech and writing skills. It is the dominant brain when a human is active, and unlike the other two brains it works at a conscious level. This part of the brain structure allows human being to think, act and plan for future as well.
The interesting facts about the evolution of 3 parts of our brain has raised interest in people of various background, including neuroscientist, psychologist and various other researchers. It could be a great start for high school students to begin their research on brain anatomy. Triune theory is not limited to brain study and its evolution but in understanding human behaviors and psychology. For example, Howard Bloom refers to triune theory in his book The Lucifer Principle to explain human behaviors.
Related article: The Role Our Three BrainsTag(s) : brain anatomy, brain structure, brain model, neuroscience, human body, behaviour,