Biological Model of Addictive Behaviour

Initiation - Low Dopamine;
-Lerman et al. showed that people who lacked the reward gene have fewer dopamine receptors in the pleasure centre of the brain and therefore are more susceptible to addiction.
-Nicotine increases dopamine release in the brain and gives a positive feeling.
-Therefore individuals are likely to use it to compensate for their deficiency by stimulating what few receptors they have.

Maintenance/Relapse - Nicotine Regulation Model;
-Chemical Addiction/Dependency.
-Suggests people maintain/relapse because going without nicotine is unpleasant.
-Clear evidence that nicotine is extremely addictive and produces significant changes in how the brain functions such as increased dopamine levels.
-Smokers start to experience impairment of mood and concentration within hours of last cigarette
-Long term withdrawal symptoms (Headaches, anxiety, nausea, cravings.) alleviated by smoking, therefore the cycle is maintained and there is relapse to avoid symptoms.

Initiation - Volkow et al. & The Role of Dopamine;
-Gave Ritalin to a group of adult volunteers
-Some loved the feeling, some hated it
-Researchers produced brain scans of volunteers; Those who loved it had fewer dopamine receptors than those who hated it.
-Concluded that some people are particularly vulnerable to the added rush whereas others have a dopamine circuitry that can't handle the additional stimulation.
-Findings can explain why some people develop and addiction whilst others don't.

Maintenance - Schachter;
-Compared how many cigarettes different smokers needed to consume each week.
-Participants were given cigarettes with either high or low nicotine levels.
-Those with low nicotine cigarettes smoked more than those with high, particularly observable in heavy smokers who smoked up to 25% more low nicotine than high.
-Argues that smokers continue to smoke to maintain nicotine in the body at a level high enough to avoid withdrawal symptoms.

Practical Applications to Prevent Relapse;
-Advantage is it can explain the biological basis of addictive behaviour and can therefore inform pharmalogical treatments e.g. Nicotine patches which steadily release a low dose of nicotine through the skin to minimise withdrawal symptoms and lessen cravings. Such an approach removes the physical dependency removes the physical dependency and withdrawal symptoms, therefore significantly reducing risk of relapse.
-The effectiveness of these treatments offers support to the biological model, suggesting the model is based on correct assumptions.

General - Lacks explanatory power;
-Biological explanation is reductionist as it reduces complex phenomenon of addiction down to simple explanation of chemical dependency
-Can't be purely biological as one of the biggest struggles for addicts is breaking the learned habits.
-Nicotine inhalers help remove both the chemical craving for nicotine and the key behaviours linked to smoking (i.e raising a cigaette to the mouth and inhaling). This highlights the benefits of an eclectic approach to help understand addictive behaviour.

Initiation - Genetic Vulnerability;
-Black et al. found that first-degree relatives of pathological gamblers were more likely to suffer from pathological gambling than more distant relatives, demonstrating a strong genetic link.
-Suggestion that pathological gamblers inherit certain personality traits that predispose them to need intense stimulation and excitement which makes it likely for them to engage in risk-taking behaviour.
-Zuckerman proposed the personality characteristic of sensation-seeking. Blasczynski et al. found that poor tolerance for boredom may also contribute to gambling behaviour.

Maintenance - Physical Dependency Theory;
-Suggests that people maintain an addiction because going without is unpleasant
-Example - placing a bet can be followed by a period of anticipation where the body prepares for an outcome with an increased flow of adrenaline and increased heart rate. After the outcome is reached there is a drop in these levels which makes the person want to re-engage in the behaviour.
-Risen pulse rates slow down (quicker in seasoned gamblers), therefore need to engage in more and more risky behaviour, placing bigger bets or playing faster in order to maintain the positive feelings it gives

Relapse - Withdrawal symptoms;
-Wray and Dickerson; Gamblers who are prevented from gambling report withdrawal symptoms.
-Over 60% of pathological gamblers reported physical side-effects similar to those associated with drug withdrawal when they didn't gamble. (Increased heart rate, raised blood pressure, tremors, sweating and insomnia)

Supporting Evidence for the Initiation of Gambling;
-Slutske et al. (2000)
-65% of the variation in the risk for pathological gambling could be accounted for by genetic factors alone.
-Suggests environmental factors were less significant than heritability in their contribution to gambling behaviour, supporting biological explanation for initiation of gambling.

Supporting Evidence for the Maintenance/Relapse of Gambling;
-Meyer et al. (2004)
-Compared a group of gamblers when they were playing for real and when they were playing cards but not for money (control group)
-Found that problem gamblers showed an increase in cortisol secretion and an increase in heart rate.
-EEG scans of gamblers also show heightened responses to images of gambling, similar to the response drug addicts show to images of drug paraphernalia

General - Incomplete Explanation;
-Environmental factors such as parental attitudes can't be ignored
-Appears addictive gambling is likely to result from both dispositional and sociocultural factors and the complex interaction between them. E.g. not surprising to find that people with higher access to gambling opportunities are more likely to become problem gamblers.
-Sharpe (2002) proposed a biopsychosocial model and suggested three main early contributory factors; biological vulnerability, family attitudes that support gambling, high levels of impulsivity.
-Complicated but realistic view of gambling that involves the interaction of different factors operating at different levels
-Therefore an eclectic approach may best explain gambling behaviour.