The Influence of Stress on Dopamine Levels :: Biology Essays Research Papers

The Influence of Stress on Dopamine Levels In the quest to survive, every living organism is equipped with the armor to withstand the impacts of stress. The African savanna leaves the zebra in an anxiety-ridden position of vulnerability to predators. Stress may can be as basic as the lack of food, habitat, or reproductive success. Humans are especially aware of the impacts of stress due to the nature of todayà ¢s contemporary lifestyle. Too many daily demands can give a person anything from insomnia to indigestion to depression. Every person is equipped to naturally deal with large amounts of stress, but when these amounts exceed what the body can handle, discomfort is considerable. Besides the qualitative approach to coping with stress, what bodily mechanisms are responsible for dealing with anxiety? The nervous system is almost solely credited with this task. The complex interaction system between billions of individual neurons facilitates large number of behaviors that result due to inputs originating inside and outside the organism. Spaces between neighboring neurons are called synapses, and one way in which they communicate is by sending chemical signals called neurotransmitters across the presynaptic membrane to the postsynaptic membrane. Years of nervous system research have determined that stress activates the neurotransmitter, dopamine. The functions of dopamine are numerous, but in general it inhibits transmission of nerve impulses. This transmitter is found throughout the body, though mainly housed in the brainà ¢s interior basil ganglia, in the frontal lobe of the information-processing center of the brain, or in the limbic system (1). Many chronic diseases result from the overproduction or underproduction of dopamine. The dopamineà ¢s inability to move into the frontal lobe of the brain results in the inability to control fine motor movement and is familiarly called Parkinson Disease(1) . If the flow of dopamine throughout the nervous system is not allowed to circulate as usual, then schizophrenia follows (1). Now that the extreme abnormalities of dopamine have been discussed, letà ¢s look at how dopamine affects the average person who is subjected to a stressful environment. One study maintains that the chewing behavior of mice is a response to stress, and therefore it serves as a coping device. The body responds to stress by the activation of the cerebral dopaminergic (DA) system. The study shows that when given the option of chewing, the activation of mouse DA system is drawn out (2) In other words, when allowed to chew, a mouseà ¢s body will have prolonged the presence of stress-managers; this coping mechanism reduces the impact of the stress.