Biological explanations for smoking
Individuals may be genetically predisposed to finding smoking more rewarding. Specific genes have been proposed to explain why a person may initiate in smoking. However, it is now believed multiple genes influence a person's likelihood of initiating smoking behaviour. These multiple genes could lead to genetic differences predisposing individuals to engage in smoking behaviour e.g. biochemical pathways. For example, Liebman and Cooper suggested those with more sensitive Dopamine pathways were more likely to become addicted. There is evidence supporting dopamine's involvement in smoking addiction but it is reductionist to say that all addiction is due to more sensitive biochemical pathways.
However, Shields' 42 twin pair study found that only nine pairs were discordant for smoking behaviour. That is, nine twin pairs did not correlate with smoking behaviour. This can be seen as evidence for environmental factors as the twin pairs share the same genes. Nevertheless, it can be argued that twin pairs also share similar environments so further biological explanation is needed.
Schacter's physical dependence theory can be seen as another biological explanation as he argues smokers maintain their habit to keep their nicotine levels at a high enough level to prevent withdrawal symptoms. Furthermore explanations for maintenance supporting this view is Epping-Jordan. He found that rats given nicotine needed a lower voltage shock for pleasure than controls to experience the same feeling of pleasure, suggesting that smoking addiction can make other experiences more pleasurable. However, this study can be criticised as it is unclear here how "levels of pleasure" were measured and may merely be subjective.
In terms of relapse, withdrawal symptoms have been thought to be the reason why many relapse e.g. due to mood swings, fatigue etc. These effects may lead to the abstainer to believe they cannot physiologically cope without smoking and so relapse. Supporting this, Lerman et al found higher activity in certain parts of of the brain of those abstaining from alcohol than controls, suggesting a biological basis. However, it can be argued that this study is testing alcoholism and cannot necessarily be generalised to smoking addiction. Nevertheless, smoking and alcohol addiction are both substance-related disorders so comparisons may be made.
To conclude, the biological explanation can be seen as a strong explanation for the initiation, maintenance and relapse of smoking addiction, however, the belief that genes dictate ones behaviour is largely deterministic as it removes free will. Furthermore, the approach is also reductionist as it reduces addictive behaviour purely to biological factors e.g. genes, biochemicals etc. For…