Addiction
Specification:
1. Describing addiction: physical and psychological dependence, tolerance, and withdrawal
syndrome.
2. Risk factors in the development of addiction, including genetic vulnerability, stress,
personality, family influences and peers.
3. Explanations for nicotine addiction: brain neurochemistry, including the role of dopamine,
and learning theory as applied to smoking behaviour, including reference to cue reactivity.
4. Explanations for gambling addiction: learning theory as applied to gambling, including
reference to partial and variable reinforcement; cognitive theory as applied to gambling,
including aversion therapy and covert sensitisation.
5. Reducing addiction: drug therapy; behavioural interventions, including aversion therapy and
covert sensitisation; cognitive behaviour therapy.
6. The application of the following theories of behaviour change to addictive behaviour; the
theory of planned behaviour and Prochaska’s six-stage model of behaviour change.
1. Describing addiction: physical and psychological dependence, tolerance, and withdrawal
syndrome.
AO1 (don’t need AO3 for this spec point).
Addiction = a state characterised by compulsively engaging in rewarding stimuli despite the
associated adverse consequences
Walters et al defined the 4 ‘P’s in addiction:
- Progression – as the addictive behaviour progresses, so do the tolerance levels.
- Preoccupation – the behaviour dominates the thoughts of the individual.
- Perception – the individual feels no control over the behaviour; it controls them.
- Persistence – the person continues the behaviour despite the problems of tolerance,
dependency and withdrawal.
Physical dependence = when an individual needs to take the drug in order to feel ‘normal’
and can occur with long-term use of a drug. It can be demonstrated by the presence of
withdrawal symptoms when the use of the drug is reduced or stopped.
- Often follows heavy daily use over several weeks or longer.
- Does not necessarily mean individual = addicted but physical dependence usually
accompanies addiction.
- Often accompanied by increased tolerance to the drug.
Psychological dependence = when a drug becomes a central part of an individual’s thoughts,
emotions, and activities, resulting in a strong urge/ compulsion to continue taking a
substance or continue performing a behaviour because its use is rewarding.
- Results in addicted individual still taking substance or engaging in behaviour until it
becomes a habit despite the harmful consequences.
- A characteristic of both types of dependence = cravings (intense desire to repeat the
experience associated with particular drug or activity).
- If cravings aren’t met – individual feels v anxious + may feel unable to cope.
, Tolerance = a reduction in response to a substance, so that an addicted individual needs
more to get the same effect. Caused by repeated exposure to the effects of a substance.
There are 3 ways tolerance can occur:
- Metabolic tolerance = the enzymes responsible for metabolising the drug do this more
efficiently over time. This results in reduced concentrations in the blood and at the sites
of drug action, making the effect weaker.
- Prolonged drug use leads to changes in receptor density, reducing the response to the
normal dose of the drug.
- Learned tolerance = user will experience reduced drug effects because they have
learned to function normally when under the influence of the drug.
Withdrawal syndrome = a set of symptoms (e.g. shaking and anxiety) that develop when an
addicted individual abstains from or reduces their use of a substance that they are physically
dependent on.
- Acute withdrawal – begins within hours of drug cessation and gradually resolves after a
few weeks. During this stage, the physical cravings are intense and persistent, as the
body adjusts to the absence of the substance it has used for so long. Relapse is highly
probable because of the intensity of the physical cravings.
- Post-acute withdrawal – can last for months or years after the person has topped taking
the drug. It is characterised by emotional and psychological turmoil as addicts
experience alternating periods of dysfunction and near-normality as the brain slowly re-
organises and re-balances itself. This indicates neuro-transmissional components as a
factor in addiction.
2. Risk factors in the development of addiction, including genetic vulnerability, stress,
personality, family influences and peers.
Genetic vulnerability: any inherited predisposition that increases the risk of a disorder or condition.
AO1
The A1 variant of the DRD2 gene is more common in people addicted to alcohol or cocaine.
Non-smokers are more likely than smokers to carry a protective gene, CYP2A6, which causes
them to feel more nausea and dizziness from smoking.
Slutske et al interviewed 2889 pairs of twins. MZ twins had a higher rate of both twins being
pathological gamblers (if one twin was a pathological gambler) than DZ twins, suggesting a
genetic influence on addiction. The closer the genetic relatedness between 2 individuals, the
higher the concordance rates.
Cross cultural research: Tsuang et al, investigating illegal drug addiction on a sample of 3000
male twins in Vietnam; and Kendler et al, investigating alcohol addiction on a sample of 9000
Swedish twin pairs found higher concordance rates between MZ than DZ twins.
Fidler et al found that those with a parent and a step-parent who smoked were more likely to
report smoking than those who did not have parents who smoked and that students who
reported at 11-12 that just a step-parent smoked were significantly more likely to report
smoking at some point during the study. They found smoking by a non-biological parent
appeared to be at least as influential as smoking by biological parents, suggesting
environmental factors = far more important than genetic factors in terms of initiation.
AO3
Lots of high-validity research support such as:
, - Cross-cultural twin studies (Tsuang et al + Kendler et al) – both support the presence of a
clear genetic component involved in addiction. Both have high pop val, large sample
sizes + the cross-cultural element reduces the likelihood that environmental influences
are at play.
- BUT small limitation = all male participants in Tsuang’s study limiting pop val, especially
because research has shown genetic influences on addiction are different for males and
females.
Real-world application
- Genetic vulnerability research explains why some develop addictive behaviour, yet
others with similar/ same life experiences don’t.
- Useful because those who have the A1 variant of the DRD2 gene can be aware they’re
more susceptible to developing an alcohol or cocaine addiction + hence can take
preventative measures (e.g., avoiding substances).
- Same for those with family members prone to addictive behaviour. E.g., some relatives of
alcohol addicts choose to not have alcohol despite never being addicted themselves.
- Also useful for doctors + counsellors as it provides greater insights into how to help
addicted patients, or those at risk of addiction.
To solely focus on genetic explanation to addiction = biologically deterministic.
- For many twin studies e.g. Kendler et al, concordance rates for MZ twins aren’t 100%
despite MZ twins sharing 100% of genes. Therefore, genetics can’t be only factor.
- But the sig concordance rates indicate that environmental factors are also not the only
factors at play. Research suggests biological and environmental determinism both =
flawed explanations + it’s instead a combination of the two.
- Example: Shinohara et al found raised levels of dopamine + noradrenaline occur in social
gamblers only when they are gambling, but occur in anticipation of gambling and in
response to gambling paraphernalia in pathological gamblers, suggesting learning
processes and biology are involved in gambling dependency.
Stress: a state of physiological arousal produced by stressors (demands from the environment).
AO1
Self-medication
- The self-medication model proposes that some individuals intentionally engage in
pathological behaviour (e.g. alcohol, drugs, gambling) to ‘treat’ the psychological effects
of every-day stressors in their life.
- Research on drug abusers shows stress = one of the strongest predictors of relapse +
increased drug cravings.
Traumatic stress – people exposed to severe stress are more vulnerable to addictions.
- E.g., Robins et al interviewed US soldiers within a year of their return from the Vietnam
war. Almost half had used either opium or heroin during their tour of duty with 20%
reporting they developed physical or psychological dependence on heroin during their
time in Vietnam.
- Driessen et al found 30% of drug addicts + 15% of alcoholics also suffered from PTSD.
AO3
Limitation: reductionist to imply stress = only cause of addictive behaviour.
- Ignores genetic influences e.g. Slutske et al illustrates the genetic influence on gambling
addiction.
