Specification
An addiction is…“A state of Addiction is a
state of periodic or chronic intoxication
produced by repeated consumption of a drug,
natural or synthetic”(World Health Organisation)
“An addict is a person addicted to a habit, especially
one dependent on a drug” (OED)
The central feature of drug addiction is compulsive drug use - loss of control over apparently voluntary acts of drug seeking
and drug taking (Goldstein, 1994).
Addiction Unit Spec & Qs
Substance related disorders = Smoking Impulse control disorders = Gambling
Explain and Evaluate the Biological Approach to Addiction
Answer & Peer mark:Outline and evaluate the biological model as an explanation for the
maintenance of one addictive behaviour. (4 marks + 4 marks)
What is addictive behaviour?The DSM-V has 2 categories:
1.Substance related disorders (smoking)
2.Addictive disorders (gambling)
50 word
wonder!Choose one and summarise in
50 words – MAX!Check your neighbours!!
Can an addiction be inherited?
100% InheritedGenetics(Nature)
100% EnvironmentLearnt(Nurture)
The Biological Approach to Addiction
In each model we look at:
Initiation
Maintenance
Relapse
Definitions…
Write a definition for each
InitiationThe process of
becoming addicted
MaintenanceAddictive behaviour continues due tolerance or withdrawal
(even when aware of the undesirable consequences)
CessationWhen an addictive
behaviour is treated or stopped and
finally terminated completely
RelapseAfter a behaviour
has been terminated; signs
and symptoms begin to show again.
Can an addiction be inherited?
100% InheritedGenetics(Nature)
100% EnvironmentLearnt(Nurture)
The Biological Approach to Addiction
The Biological Approach to Addiction
The Brain!
What is the focus of the Biological Approach?
What neurotransmitters are involved?
How can genetics explain gambling?
How does it link to the behavioural approach?
Assumptions:Addiction is an illness
Addiction is irreversible
Emphasis on
treatment
InitiationAddictive drugs trigger the release of
dopamine - reward systemWhile the full diversity of drug effects is mediated by multiple
neurotransmitters acting in multiple brain regions, most addictive drugs share the common property of increasing dopamine release in
the striatum (e.g., Di Chiara and Imperato, 1988; Kuczenski et al., 1991).
Opiate (pleasure) pathways can be directly stimulated by heroin, alcohol and nicotine
Susceptible people to addictions are born with a more sensitive mesolimbic dopamine pathway
(Liebman and Cooper, 1989)
Mesolimbic pathways: spontaneously release small amounts of dopamine to maintain stable moods.
Maintenance
Persistent exposure to a drug eventually leads to a reduction in brain activity
Greater Tolerance = More drug useGreater Withdrawal
Draw a representation of this…
Less effect…
Relapse
Lasting memories maintain the need for the drug and the positive rewards.
Addicts crave the dopamine rush (not just the drug!)
Genetic Predisposition
Alcohol disorder patients: 36% of
their relatives also diagnosed with an alcohol disorder
(Merikangas et al, 1998)
Heritability of nicotine dependence has been estimated at 60-70% (Kendler, et al, 1999)
Heritability of alcohol dependence has been estimated at 39-60%
(Heath and Martin, 1993)
Can an addiction be inherited?
100% InheritedGenetics(Nature)
100% EnvironmentLearnt(Nurture)
The Biological Approach to Addiction
Evaluation Game!
Create an acronym or
image story to
remember these
terms
GeneralisabilityReliabilityApplicationValidityEthics
Evaluation Game!
Now apply them
to the Biological
Approach
GeneralisabilityReliabilityApplicationValidityEthics
Individual differences: genetic predisposition or
resistance?
Does everyone become an addict?
Nature AND nurture?
Much of the data is correlational…
What about Gambling?
Outline and evaluate the biological model as an explanation for the
maintenance of oneaddictive behaviour. (4 marks + 4 marks)