Dopamine Essay, Research Paper

Dopamine

An integral component of the Central Nervous System is dopamine. Dopamine is a neurotransmitter which plays a major role in carrying out two activities of the CNS. Dopamine assists in controlling movement, and it is strongly linked with behaviors based on emotion. Neurons from an area of the brain, substantia nigra, which connects to the corpora striata is the area from where dopamine is released. This pathway is involved in movement control and the musculoskeletal system. The mesocorticolimbic pathway is the second pathway that dopamine plays a major role in. The neurons of the ventral tegmentalarea send dopamine to neurons which are connected to the limbic system. The limbic system is important as it regulates emotion, motivation, behavior, smell, as well as various other involuntary actions.

There are quite a few dopamine related neurological problems. Among these are narcolepsy, Huntington’s chorea, and Parkinson’s disease. Narcolepsy is a disorder which causes people to fall into recurring episodes of deep sleep and is caused by a high level of dopamine and acetylcholine. Huntington’s chorea is an inherited disease which is caused by a high level of dopamine in the brain. The fatal illness stems from the base of the brain where neurons are progressively destroyed. Parkinson’s disease, an illness associated with tremors in limbs and muscular rigidity, is caused by the death of neurons in the nigrostriatal pathway. The lack of these neurons results in a low level of dopamine. People suffering from Parkinson’s have trouble walking, writing, and speaking. Luckily, the drug levodopa, also called L-dopa causes the remaining neurons in the nigrostriatal pathway to increase dopamine production. Another disorder, schizophrenia, is a psychiatric problem which affects contact with reality and changes in personality. People suffering from the disease have a normal level of dopamine, however, they are very sensitive to it. The drug Thorazine blocks the action of dopamine and decreases the symptoms of schizophrenia.

Individuals addicted to alcohol, cocaine, and nicotine have a lower than normal level of dopamine in their mesocorticolimbic pathway. When the aforementioned drugs are used, dopamine levels go up and a pleasurable feeling results. The feeling is in part related to the fact that dopamine inhibits the CNS. This process’ end result is a lower level of dopamine in the important pathway.