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)