The Autonomic Nervous System is a complex system that incorperates nerves and ganglia. (Dictionary.com) This system supplies blood vessels, heart, smooth muscles, viscera, and glands. It also controls the involuntary functions of all these parts. (Dictionary.com) The Autonomic Nervous System plays a major role in fear response. The Autonomic Nervous System helps regulate blood pressure and heart rate. It also helps adjust and adapt to the environment in stressful situations. There are three different respnses:biochemical, emotional, and physical responses. (Fritscher, 2008) The biochemical response is universeral and the same throughout. The emotional response is highly individualized. (Fritscher, 2008) The physcial response includes: sweating heart rate increase, high adrenaline levels, “fight or flight” response, or even evolutionary development.
The brain is one of two parts of the Central Nervous System. The brain and the spinal cord functions to be the control center. (Marieb, 2008) The brain maight be the “Head Honcho” but there are smaller parts that make the brain this way. Some of the smaller parts are the: thalamus, hypothalamus, sensory cortex, hippocampus, and the amygdala.
The thalamus is one of the first parts of the fear equation. The thalamus is located above the brain stem. The thalamus brings in sensory impluses which passes through to reach the cerebral cortex. (Dictionary.com) It brings in information to be processed. Once understood the information is then relayed to the next section of the brain. (The Nemours Foundation, 2010)
The sensory cortex is a section in the brain, located in the cerebral cortex, that is concerned with the receiving and interpreting sensory information. (Dictionary.com) The sensory cortex recieves information through the senses: eyes, nose, mouth, and ears. There are also the touch and temporature differences in the body. Each region in the sensory cortex is responsible for certain sensory perception. (Smith, 2010) The sensory cortex interprets the sensory data then sends it to the next part of the brain.
The hippocampus is located next to the mammilary body in the brain. (Marieb, 2008) When the hippocampus recieves information, its first job is to store the information. (Layton, 2010) Information is placed in the memory until this same information is recognized again. (The Nemours Foundation, 2010) When recognized the hippocampus retrieves the information from the conscious memories. Once the hippocampus’ job of storing and retrieving information is done the amygdala takes over.
The amygdala is located on the end of the caudate nucleus. (Marieb, 2008) The amygdala’s job is to decode emotions. (Layton, 2010) It determines if there is a possible threat. If not, then it passes. The amygdala stores all these memories of fear.
The hypothalamus is located on top of the brinstem. The hypothalamus is the main center of the autonomic nervous system. (Marieb, 2008) The hypothalamus’ functions are to regulate: temperature, food intake, water balance, thrist, biological rythums and drives. (Marieb, 2008) It also initiates the “fight or flight” response. (The Nemours Foundation, 2010)