Biological Explanations of Addiction

The biological model of addiction’s basic premise is that addiction: is an illness; that it is irreversible; that you are either addicted or not (there are no slightly addicted individuals) and that treatment must be medical.

There are many models of biological addiction mainly because current psychological research suggests that different areas of the brain are involved in different addictions (quashing the idea of an addictive personality per say).

In this essay two biochemical theories will be discussed, plus the genetic model. The latter theory should not be seen as distinct from the biochemical theories as biologists would propose that any biochemical abnormalities that may predispose an individual to addiction are probably inherited. Thus studies looking at concordance rates of addictions in families, twins and adopted children would support all three of the models being discussed.
One of the most popular theories of addiction is to do with the neurotransmitter Dopamine. Dopamine is involved with our pleasure/reward system. Anything we do of our volition that is pleasurable increases Dopamine. It is the release of dopamine that makes us feel Euphoria/pleasure. Drugs such as Cocaine, Alcohol and Heroin make Dopamine receptors release enormous amounts of Dopamine, so the user may feel intense pleasure. This however, does not explain addiction as many people drink or recreationally use cocaine and don’t become addicts. The main idea of the theory is that individuals biologically susceptible to addiction have more sensitive Mesolimbic/ reward pathways in their brain, e.g. drugs may have a more profound (wow factor) on their Dopamine receptors.

Another theory that may work alone or in conjunction with the Reward theory is that individuals with addictions may naturally produce low levels of Serotonin. Serotonin is thought to be a major factor in controlling our behaviour. So most of us can get drunk overeat etc but not repeat the behaviour compulsively. This is because our Serotonin levels are stable. It is thought that individuals with low levels may not be able to exercise control. There is support for this idea, e.g. low levels of serotonin are correlated with compulsive suicide, homicide, Bulimia and ADHD.

This is a preview of the whole essay

Another suggestion has been that there is a genetic basis for developing an addiction. Although a specific gene has not been found, there is plenty of research that shows high levels of concordance between families who are addicted to: alcohol (Sarafino), Nicotine (Agrawal and Lynskey, Heroin (Devaux and Krebs) and Fowler (see Erika Cox book). However like all correlational studies this kind of research cannot imply cause. The concordance could be caused by environmental factors or social learning.

Additional support for the biochemical theories comes from MRI and PET scans, animal studies using agonists and antagonists and invasive brain techniques on animals, such as neuro toxins where Dopamine receptors are removed.
Initiation-The above three theories would explain why people would find it easy to become addicted to drugs, as they are genetically pre-programmed to have less control of their behaviour and Dopamine has a more pronounced effect on their brain chemistry.

Maintenance and Relapse: Continued drug use has an adverse effect on the brain’s chemistry. It is thought that Dopamine receptors may not produce normal amounts of Dopamine after drug use; so the user has what is known as a ‘come down’ or withdrawal. Now not only do they have to get used to living without the high levels of Dopamine the drugs gave them but when they stop they may feel worse then before. Normal activities that gave them pleasure before are no longer pleasurable because less Dopamine is being produced now. This is confounded further if the person has been using drugs for some time as they have built up a tolerance, i.e., they need more drugs to maintain the good feelings because their brain chemistry has got used to the higher amounts. This means this giving up will be harder then for the novice user as the experienced user has a bigger mountain to climb down. Maintenance. This is maybe why drugs users continue to take drugs when they have adverse effects on their health and social lives. They cannot face life without them.

Reductionistic- Doesn’t explain non drug addictions such as gambling and shopping
Doesn’t consider how addiction might be better understood eclectically as cues, friends and culture, parental; attitude, cognitions etc will also contribute.
Deterministic. Sees drug adduction as inevitable and incurable so depressing but doesn’t blame individual or parent.
Nature approach,
Psychology as a science good for PET and animal studies but bad with correlational concordance too many variables to isolate. Also can’t study humans a lot as unethical to give drugs to.
Cultural bias? Only happens in western soc so can’t be just biological

Brain is too complex to pin down specific neurotransmitters and/or genes, don’t know how they effect other neurotransmitters
DRD2 has been linked to alcoholics in 42 % of cases but why don’t 58% become alchoholics?
cannot face the depressed feelings and withdrawal effects. Relapse It is thought that it may take ages for a drugs user’s brain chemistry to return to normal. Relapse may therefore occur because the user may not be able to cope with months of depression. This can be even worse for users who start as teen agers as the brain is thought to be permantly damaged. It may takes years for the brain to regenerate Dopamine pathways in other arrears of the Mesolimbic system.

There are countless instances of people who live in exactly the same environment(two siblings) but addiction is only present in some cases. Bio explanations help to account for inherent vulnerabilities and susceptibilities i.e. at the initiation stage, some people are predisposed towards addictive behaviour and also provide a person as to why some people may be more resistant to addiction treatment and more prone to relapse.

A deeper problem with neurochemical explanations is the neglect of the social contexts of the behaviours. The pleasures and escape associated with taking a drug are highly varied and depend on the person, dose, social situation they are in and the wider social context of the society they live in.

Teacher Reviews

Here's what a teacher thought of this essay

Linda Penn

24th of Sep 2013

Summary This essay includes quite a lot of information but it lacks good organisation and the writing seems hurried. Start with a good introduction to the subject of addiction with a definition or two. Then the main content needs to be planned better explaining what is meant by the biological model. The writer could then go on to look at the different biological theories citing various studies. The essay then should draw all the information together and weigh up the pros and cons in a final conclusion. Score 3*

Did you find this review helpful? Join our team of reviewers and help other students learn