The Nervous System
The nervous system is divided into two main areas, the peripheral nervous system and the central nervous system. The central nervous system controls the brain and spinal cord. The average human brain weighs approximately 3 pounds and contains approximately 100 billion neurons, as well as trillions of “support cells” called glia. The spinal cord weights approximately 35-40 grams and is around 43 cm long in adult woman and 45 cm long in adult men. The frontal lobe of the brain controls our judgement and is responsible for reasoning, planning and carrying out complex tasks. The frontal lobe works together with the amygdala. This is the part of the brain which is linked with emotional memory. The prefrontal cortex (part of the frontal lobe) analyses a situation, such as a student about to walk into an exam hall to take an important exam, and if the individual’s actual coping ability conflicts with the individual’s perceived coping ability i.e. the student panics and feels they are not fully prepared, then the amygdala will highlight that there is a problem. Depending on the actual problem, the prefrontal cortex can negotiate with the amygdala and try to defuse the situation. For example, the prefrontal cortex will try to reason with the amygdala and tell the amygdala to stop worrying and that they have prepared enough. However, in extreme circumstances, such as if the individual begins to doubt their self esteem, the amygdala can neuro hijack the prefrontal cortex resulting in extreme stress such as rage. The amygdala then signals the hypothalamus releasing the neurotransmitter chemical noradrenaline which activates the sympathetic branch of the autonomic nervous system, part of the peripheral nervous system.
The peripheral nervous system is divided into two parts, the somatic nervous system and the autonomic nervous system. The somatic nervous system is responsible for voluntary movement by carrying information from the