Transcript The Biological Model (Medical)

Check your homework answers
for the evaluation points of the
Theory of Planned Behaviour:
A strength of the theory of reasoned action (TPB) is that it has research
studies to support the fact that it can explain addictive behaviour.
A meta-analysis by Armitage and Connor (2001) found that perceived
behavioural control more accurately predicted individual’s intention to
behave when compared to looking at attitudes and subjective norms
alone.
This shows that the principles of the TPB can accurately predict how
people will behave in terms of their likelihood to engage in addictive
behaviour.
However, a limitation of this research is that it may not predict actual
addictive behaviour accurately.
This is because their meta-analysis showed research into the TPB
found it was only accurate in predicting intention to change rather
than actual behavioural change – therefore explaining how people may
be motivated to change and intend to change but may not lead to a
change in their behaviour.
This limits the extent to which TPB can be applied to the accurate
prediction of health behaviours in clinical settings, as it may be
primarily an account of intention formation rather than clearly
specifying the processes involved in translating intention into action.
However, a further strength of the TPB is that it is supported by the
principles of the cognitive model of addiction.
This model assumes that humans are in control of their own behaviour
and have the free will to choose whether to engage in an addictive
behaviour or not. This is in contrast to a deterministic view such as the
biological perspective that states addictive behaviour is the result of
‘faulty’ genes or an imbalance of neurotransmitters or hormones.
Thus, both the TPB and the cognitive approach acknowledge the
complexity of human thought processes and their influence on
addictive behaviour.
However, a limitation of the TPB is that there is research evidence that
other models may provide better alternatives for explanations of
behaviour change.
For example, ‘Stages of change’ model suggests an individual must be
ready for change and tries to get them to a position where they are
highly motivated to change behaviour, taking into account that most
people who take action to change an addiction are not successful at
first. Moreover, this model has been successfully used in smoking
cessation clinics.
Therefore, this model may be more productive at explaining nonconscious behaviours such as addiction as opposed to the TPB which
could be said to fail to take into account emotions and compulsions of
addiction.
On the other hand, a weakness of the TPB is that the very existence of
approaches other than the cognitive model of addiction suggests that
this theory alone is not enough to account for and prevent addictive
behaviour.
This model only explains addictive behaviour at the level of thought
processes and behavioural intentions and fails to acknowledge that
addiction may be learned through the process the operant
conditioning, when addicts engage in addictive behaviour because of
the positive reinforcement they receive (e.g. feeling relaxed or high).
In order to explain the complex nature of addiction, a more holistic
view should be taken that encompasses a bio-psych-social perspective.
Task
 Complete pages 51 – 54 in your booklets on biological
interventions to treat addiction.
Main neurotransmitters for
addiction
 Serotonin - helps regulate mood (e.g. anxiety and
depression). Too little has been associated with
depression (neurons using this found in pons)
 Dopamine - plays a role in mood, particularly
motivation and reward (as well as cognition, learning
and memory).
 Endorphins - produced in pituitary gland during
exercise, excitement and pain.
 Dopamine agonists
 Dopamine antagonists
Treatment for smoking
1. NRT – replace nicotine from cigarettes with
nicotine from safer sources (patches, gum, spray,
inhalers). Small amounts of nicotine contained
within the gum or patch which is absorbed into
the blood, giving body nicotine it thinks it needs.
Purpose behind NRT to slowly reduce dosage.
Little by little, less nicotine until, eventually, you
not needed anymore.
A02 - May double rates of quitting. BUT smokers
may continue to smoke in addition to
intervention.
2. Varenicline – drug that acts as nicotine receptor
partial agonist; attaches to receptors to partially
stimulate receptor, without creating full nicotine effect
to alleviate craving and withdrawal symptoms and
reduce rewarding effects of smoking. Secondly, blocks
the ability of nicotine to stimulate the central nervous
mesolimbic dopamine system.
 A02 – Varenicline: side effects are common, has been
associated with depression and suicide – patients need
careful monitoring
3. Antidepressants - e.g. bupropion and nortriptyline
(tricyclic antidepressants) – inhibits the reuptake of
dopamine, serotonin and noradrenaline, allowing
chemicals to stay in the brain for longer
A02 - Hall et al (1988) found antidepressant
nortriptyline assisted quitting, especially if used
alongside CBT, BUT have more serious side effects
than newer SSRIs (which are not effective in treating
smoking)
Treatment for gambling
1. Opioid antagonists – prevent the pleasure
experienced when gambling by attaching to (i.e.
blocking) dopamine receptor sites, therefore
diminishing desire to gamble (theory is that
repeated lack of effects from gambling breaks the
habit)
A02 - Grant and Kim (2006) found gamblers
experience rush of excitement and that
naltrexone reduced thoughts about gambling
and urge to gamble, and at higher doses, reduced
actual gambling.
2. SSRIs – gamblers been found to have low levels of
serotonin (more likely to engage in sensation-seeking
behaviour) – as serotonin is low SSRIs should be
effective.
A02 - Kim et al (2002) found SSRIs reduced gambling
symptoms compared to placebo condition.
3. Mood stabilisers (e.g. Lithium) –target impulsivity
associated with impulse-control disorders such as
gambling by altering the way the body breaks down
neurotransmitters: increases effect of serotonin (a
neurotransmitter that plays a role in stabilizing
moods) and also decreases the levels of the
neurotransmitters norepinephrine and dopamine, and
prevents the nerve receptors from becoming overly
sensitive to the effects of dopamine.
AO2
A02 - Hollander et al (2005) found Lithium more
effective than placebo at reducing gambling urges over
10 weeks. BUT, drug group did not lose less money or
gamble less than placebo group
A02 – drug treatments for gambling still at early stage
and remain experimental
Task - homework
 Listen to the pod cast and fill in the missing
information (page 54) on evaluation of biological
interventions.
 Identify the main point of each evaluation paragraph.
Optional - Exam question
 Discuss one type of intervention aimed at reducing
addictive behaviour.
(4 + 8 marks)