The Brain: The Most Complex Organ In The Human Body

The brain is the most complex organ in the human body (Psychology Today, 2014) and is the central organ of the human nervous system; with the spinal cord makes up the central nervous system. It controls most of the activities of the body, processing and coordinating the information it receives from the sense organs, hence making decisions as to the instructions sent to the rest of the body, (Wikipedia, 2010). The brain contains the limbic system which plays a key role in how an organism responds to environmental threats and challenges and thus is believed to be the key factor in whether we respond aggressively or not to an external stimulus, (Tutor2u, 2017). The limbic system is a complex system of nerves and networks in the brain, involving

“Within the limbic system, the amygdala, which is responsible for emotions and partially responsible for memory, has been found to directly influence changes in violent or hostile activity (Wright et al., 2008)”, (Renegdanoble, 2014). The amygdala is an almond-shape set of neurons located deep within in the brain's medial temporal lobe – one of the four major lobes of the brain in the cerebral hemisphere, (ScienceDaily, 2017). It is thought that people who are excessively aggressive or fearful have problems with their amygdala. This can be because their amygdala is damaged which can occur through stroke, tumour or developmental problems. Moreover, damage to the prefrontal cortex- a part of the brain located at the front of the frontal lobe near the forehead, which is implicated in a variety of complex behaviours, and greatly contributes to personality development, would reduce the inhibition of the amygdala resulting in higher levels of aggression, (Good Therapy,

It was concluded that 79% of the aggressive group were injured in their pre-frontal cortex and 49% of the non-aggressive group suffered injuries in their pre-frontal cortex, (LiveScience, 2011). These figures outline the fact that injury to the pre-frontal cortex has a positive correlation with aggression levels. Research shows that individuals with borderline personality disorder and schizophrenia are known to have damage to areas of the brain, which may account for violent propensities. This is evident as 42 studies showed that, compared to healthy individuals, Borderline Personality Disorder patients displayed ‘extensive cortical brain abnormalities in structure and function’ (Current Psychiatry, 2014). Furthermore, people with schizophrenia have about 5-7% brain shrinkage – most notably in the gray matter – an important part of the amygdala amongst other structures in the limbic system, (Schizophrenia,