Biological Viewpoint

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1. How does your assigned theoretical viewpoint (Biological) explain the causes of substance abuse, and what treatments does it recommend?

Biological theories are based on the assumption that biological neurotransmitters associated with pleasure create dependency or that there is a genetic predisposition to alcoholism; it is inherited through your genes.

1. The Pleasure Center Theory: Biological Model

It is based on early studies with rats investigating the pleasure centres of the rat's brain. For example, Olds and Milner (1954) performed an operation on a rat where a self-stimulating electrode was attached to its hypothalamus. When the electrode, which protruded from the top of the rat's skull, was attached to one part of the hypothalamus they observed the rat's behaviour. Through a lever in its cage it sent constant charges down the electrode at the rate of 100 a minute. The rat would continue to press the lever in preference to other possible rewards such as food, drink or sexual activity and would even cross a grid with a painful electric current passing through it to reach the lever and receive the pleasurable stimulation. So stimulation of this area was very reinforcing. People become addicted because they chase after the high and euphoria, which gradually takes more of the drug, with less effect (tolerance). (1)

b. A modern variation on this theory concerns certain neurotransmitters like dopamine which are a source of pleasure. Many drugs, such as heroin and cocaine affect the dopamine receptors and others, and this biological pleasure?and expected euphoria creates physical dependency. (1)

2. Genetic Theory of Addiction: Biological Model

This theory, known as addictive inheritance, attempts to separate the genetic and environmental factors of addictive behaviour. Evidence comes from twin studies, race studies and comparing alcoholic to non-alcoholic subjects. For example, Sayette & Hufford (1997) studied alcoholism and found that concordance rates in monozygotic twins were higher than for dizygotic twins. This suggests that genes, not the environment are ...