AlcoholismNature Or Nuture Essay Research Paper INTRODUCTION — страница 4

brain’s reward system produces extreme pleasure, which is reinforced more as alcohol consumption increases. Such strong reinforcement may explain why people will forego food, instead of alcoholic drinks if presented the choice. Increasing activity in the brain reward system is related to increased reinforcement, which supports the continued use and abuse of alcohol. Tolerance of alcohol develops differently in people but one thing remains consistent. That being increased activity in the nervous system or shaking occurs on cessation after prolonged use. Tolerance is developed when following a prolonged period of use, more alcohol is required to produce a wanted or given effect. The development of tolerance can contribute to the progression from use to abuse and addiction. As

alcohol dependency develops, a person must continue to drink more alcohol to avoid the unpleasant experience of withdrawal. Sensitization, the opposite of tolerance, plays a significant role in supporting alcoholism. With prolonged use of alcohol, cells in the brain adapt to its presence such that the alcohol is required to maintain normal cell function. On withdrawal of alcohol, the cell behaves abnormally and a withdrawal syndrome ensues. Generally, the withdrawal syndrome is characterized by a series of signs and symptoms, such as tremors. No matter the severity of the physical withdrawal syndrome, its existence can create a craving or desire for alcohol and dependence can play a very strong role in recurrent patterns of relapse and maintaining alcohol-seeking behavior. With

repeated cycles of abstinence and re-use of alcohol, the time required to elicit alcohol dependence grows shorter. The quantity of alcohol rather than the frequency of use have been studied to be a powerful predictor of problematic use. The two are not the same. A person who occasionally drinks but when they do does so in large quantities, can be greatly harming himself or herself. Conversely a person who drinks in moderation every day may not experience any problems in the short term, but may encounter health problems later on. The type of alcohol used also has an effect on later alcohol problems. By this I mean drinking beer or wine instead of ‘hard’ liquor such as rum and whiskey. BIOLOGICAL: Alcoholism is considered to derive from genetic causes. Family studies have

repeatedly confirmed that the risk of alcoholism is higher among parents, siblings and children. While genetics may play an important role, there are other factors that can influence individual biological susceptibility to the effects of alcoholism. Because alcohol abuse is linked to behavioral and environmental factors leads to the point that genetics act together along with other non-genetic factors. Some diseases are caused by the alteration of a single gene such as cystic fibrosis, but alcoholism is not on of these. Alcohol abuse is very likely to involve multiple genes that control various aspects of the biological response to alcohol. Research studies have not been able to explain what precisely is inherited that causes people to become problem drinkers although it may be

possible to do so. First, one way would be to identify a ‘risk marker’ or biological trait associated with alcoholism, but to date no ‘risk markers’ have been clearly identified. Second, the genetic technique of linkage analysis can narrow the area on a chromosome where a gene may be located. It can lead to the identification of the gene, which in turn can improve the understanding of the molecular events that underlie the expression of the gene. There have been few genetic linkage studies related to alcohol abuse. Third, an association between alcoholism and a gene that regulates the number of a type of dopamine receptors in the brain has been studied. One study revealed a relationship between the presence of the gene not only in alcoholics, but also in other disorders

such as autism and Tourette’s syndrome. The presence of this particular gene, while not uniquely specific for alcoholism, may cause an alteration in the brain’s dopamine system that somehow contributes to alcohol abuse. Studies in this biological field began using selective breeding amongst animals. The results do show that alcohol tolerance, the actions of alcohol, alcohol preference and alcohol physical dependence can be affected by genetics. One study found a high rate of alcohol abuse between identical twins over fraternal twins. Interestingly studies found that identical male twins are more frequent in cases of alcohol abuse and dependence than that of fraternal male twins. The same results were found in identical female twins as well. Adoption studies have also