Models of addiction
Biological- Genes - Assume that addiction is a specific diagnosis ( either you are an addict or you are not), addiction is an illness, the problem lies with the individual, the addiction is irreversible and there is an emphasis on treatment.
- It is unlikely that a single gene is responsible for addictive behaviour. It is more likely that multiple genes are involved and that different genes underlie different addictions.
- There seems to be a link between smoking and genes involved with dopamine regulation (Lerman 1999) whereas research into cannabis, cocaine and heroin addiction has found links to a gene in a different brain system (Comings et al 1997).
- Some adoption studies lend support to this approach. Twin studies offer additional support. Heritability of nicotine dependence has been estimated at 60-70% ( Kendler 1999).
- Even if we were to confirm a biological basis we would need to identify the mechanism by which the influence takes place. This may be biochemical (in terms of how various addictions are metabolised by the brain) or psychological ( in terms of how psychological factors such as personality determine behaviour. Whatever the precise mechanism is, we must understand that the addiction will only express itself if the person consumes large amounts of it. A person that is genetically vulnerable to smoking ill only become addicted if they try smoking. If they never smoke they will not become addicted. The trigger to start the addiction probably result from environmental factors.
- There are two main pathways identified as being important in the development of an addiction. The dopamine reward system and the endogenous opioid system.
- Neurotransmitters are brain chemicals…