Psychology of Addiction (The models)

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Psychology of Addiction(The models)
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The disease model

• Neurotransmitters
• The chemical that moves between nerve cells to
  transmit messages.
• If the message is blocked or replaced there will
  be a change to the physiological system and this
  in turn will effect mood behaviour and cognition.
  

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The disease model-Dopamine.

• Dopamine is the most commonly associated
  neurotransmitter with addiction.
• Dopamine is similar to adrenaline in that it
  affects brain processes that control movement,
  emotional response, and ability to experience
  pleasure and pain.
• Cocaine and other drugs of abuse can alter
  dopamine function

• Some drugs are known as dopamine agonists.
• These drugs bind to dopamine receptors in place
  of dopamine
• directly stimulate those receptors.

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The disease model- Dopamine.

• Drugs such as cocaine and amphetamine produce
  their effects by changing the flow of
  neurotransmitters. These drugs are defined as
  indirect acting because they depend on the
  activity of neurons.
• In contrast, some drugs bypass neurotransmitters
  altogether and act directly on receptors. Such
  drugs are direct acting.
• However, some drugs increase dopamine by
  preventing dopamine reuptake, leaving more
  dopamine in the synapse.
• An example is the widely abused stimulant drug,
  cocaine. Another is methylphenidate, used
  therapeutically to treat childhood hyperkinesis
  and symptoms of schizophrenia.

Thinking point At this point think about the
role of dopamine in relation to addiction e.g.
what about gambling/gaming...could you describe
how dopamine can be used as a viable theory to
explain these addictions?
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The disease model-Genetics
There is no single addiction Gene.
Scientists will never find just one single
addiction gene. Susceptibility to addiction is
the result of many interacting genes
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Dr Glen Hanson suggests

• "Just because you are prone to addiction doesn't
  mean you're going to become addicted. It just
  means you've got to be careful."

• Researchers construct pedigrees of large families
  with addiction as a first step to understanding
  the disease.
• A pedigree can reveal whether or not a trait has
  a genetic component. That is, whether or not it
  is passed down from parent to child by way of
  genes

Using pedigree data, researchers can begin to
hunt down genes. They begin by comparing DNA
sequences of individuals who have the disease
with those who do not. They can then narrow down
the possibilities to identify a small number of
so-called "candidate genes" for addiction.
Sourcehttp//learn.genetics.utah.edu/content/addi
ction/genetics/
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Glen Hanson cont

• There are many ways that genes could cause one
  person to be more vulnerable to addiction than
  another.
• Starting addictive behaviour.
• Continuing with additive behaviour.
• Activating the reward system.
• Feelings of pleasure.
• There could well be a specific gene for each!
  Remember Scientists will never find just one
  single addiction gene. Susceptibility to
  addiction is the result of many interacting genes
  
• Like other behavioural diseases, addiction
  vulnerability is a very complex trait. Many
  factors determine the likelihood that someone
  will become an addict

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The story of John James.

• John Crawford has an identical twin. His
  16-year-old brother, James, is his mirror image.
  John has brown hair, brown eyes, and a slightly
  crooked smile. So does James. John weighs about
  160 pounds. Ditto for James. The brothers walk
  the same, talk the sametheir friends tease them
  because they even bowl the same.

The reason, of course, is that identical twins
share exactly the same genes, those tiny units
of hereditary material (DNA) that carry
instructions for forming all the cells in the
body and directing their activity.
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Can addiction run in families? Let us assume John
James have a parent who struggles with
alcoholism

• Q Are they destined by genetics to face the same
  fate?
• A The good news is that no single factor
  determines whether a person will become addicted
  to drugs. Thats because genetics, biology, and
  environment all influence a persons risk for
  addiction, defined as a chronic yet treatable
  brain disease characterized by compulsive seeking
  and use.
• So, while the saying may be that substance abuse
  in particular runs in the family, a whole list
  of other risk factors in addition to genes come
  into play to determine whether a person gets
  hooked.
• Genetics
• Age,
• Presence of other diseases,
• Diet
• Stress,
• Peer pressure.

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Genetics aka addictive inheritance

• Separates the genetic and environmental factors
  of addictive behaviour.
• Studies have been done to control for
  environmental components to determine if genetics
  plays a greater role.
• Most studies looking at alcoholism have
  determined that children born from alcoholic
  parents who are adopted into non-alcoholic
  families have a three to four fold increase in
  the rate of alcoholism over the rest of the
  population.
• Indeed, children born and raised by alcoholic
  parents have an even greater rate of alcoholism.
  This suggests that there is some genetic
  predisposition to alcoholic addiction.

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Several questions we must consider at this point.

• Is it the addictive behaviour that is encoded or
  a biological mechanism that drives the behaviour?
• Are there differences in the metabolism of
  various addictive substances that allow an
  individual to have varying levels of a drug in
  the blood stream and have a psychological
  experience different someone else?
• Is there some genetic difference that perhaps
  allows some to realise when an elevated blood
  alcohol level has been reached and transmits a
  message to the brain to stop drinking that others
  do not have?

Things that make you go hmm??
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What evidence is available.

• The strongest correlation between addiction and
  genetics comes when evaluating the pattern of
  inheritance. All studies show that it is sons,
  not daughters, who most often inherit the risk of
  alcoholism.

You should at this point be critically analysing
the findings by thinking..
Could it be that sons model themselves more after
their fathers? .
Or is there a sex-linked genetic mechanism at
play that is contributing to this phenomenon?
How much of this phenomenon has its basis in
genetics.
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Further evidence

• A study using 300 MZ twins approx 200 DZ twins
  estimated the contribution of genetic factors
  environmental factors to substance use in
  adolescence.
• Findings
• Major influence on the decision was
  environmental rather than genetic (Hans et al
  1999)

• 2. Link between personality addictive
  behaviour.
• 300 MZ 300 DZ looked at relationship between
  alcohol use personality.
• Findings
• Connection between genetics anti social
  personality characteristics between personality
  changes alcoholism (Jang et al 2000)

3. Comings et al (1996) also found
similar findings in the investigation looking
into behavioural addictions such as gambling
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Let us review.

• So far we have learned there are several
  components to addiction and that defining
  addiction has not always been easy. We have begun
  to look at the disease model of addiction and
  have discussed the role of neurotransmitters
  genes.
• Now would be a good time to check our
  understanding..

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Over to you In pairs answer the following
questions on your mini whiteboards.

• According to Griffiths (2005), what are the six
  components of addictive behaviour?
• What neurotransmitter is most commonly associated
  with addictive behaviour and why?
• Why are twin studies a good method for examining
  the role of genetics in addictive behaviour.

Usual rules apply!
You have 10 mins to complete this task.
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Q What about the effects of reinforcement?..Isn't
that behaviourism?

• A Technically yes!!!
• The rule/definition Anything that increases the
  probability of a behaviour occurring in similar
  circumstances.

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Reinforcement biology! There is a crossover!

• Think classical operant conditioning.....think
  pleasure centres in the brain.
• Research 1 Olds Milner (1954) discovered rats
  would press a lever for the reward of mild
  electrical stimulation in specific areas of the
  brain. They also pressed the lever for
  stimulation of other rewards such as food or
  sexual activity.

Plug em in Rat Shock Pleasure. A type of
reinforcement...there is our tedious link!!
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Things that make you go hmmm!!!

• Pleasure is an important factor in healthy
  development. Would you eat McDonalds/Chocolate
  again if it were not pleasurable?

• These feelings act as reinforcers...therefore
  pleasure encourages essential behaviours or in
  some cases unhealthy behaviours......we all have
  our crosses to bear..Is addiction is the price we
  pay??

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Evaluation of biological explanations.

• Foes
• Neurotransmitters complex effects are not fully
  understood. Which neurotransmitters produces
  which reward? Nicotine can effect memory
  learning and increase arousal but reduce
  stress...thus difficult to pinpoint exactly what
  is going on!!!
• Social interaction is underrated. Social
  contexts- The pleasures/escapism..depending on
  the context Vietnam soldiers took drugs but
  stopped when back home (Robins et al 1975)
• Genotypes are not the full story. Emphasis on
  genetics rather than environment.

• Friends
• Biological explanations help explain disposition.
• Helps to account for Vulnerabilities
  susceptibilities' and also provides information
  on why some may relapse more than others.

Don't forget other evaluative points
too! Method, Ethics, AID, Keywords etc.
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Cognitive explanations of addictive behaviour.

• Faulty Thinking

• Irrational biases

• Example Gambling
• I will win, I can control the odds, if I use my
  lucky numbers I'll be rich one day.

• Overestimate the extent to which they can predict
  or influence the outcomes. This also leads to a
  under estimation of how much has been lost/won.
• See Griffiths (1994) Gamblers irrational
  cognitive biases.

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Evaluation of cognitive explanation

• Foes

• Friends

• Skill perception varies across individuals Cannot
  establish cause effect because skill is not
  consistent among gamblers or irrational.
• Experiential factors play a role too. Many
  gamblers on automatic pilot..suggesting cognitive
  processes did not play major role in maintenance
  of behaviour.
• Cognitive explanations may be limited to specific
  addictions May have less of an effect in chemical
  addicitions such as Heroin but better in
  understanding gambling.

• Helps explain individual differences During
  development of maintenance stage faulty biases
  may be more likely to develop problems.

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How do Heuristics apply to addictions e.g.
gambling

• Rule of thumb The usual rules apply.
• Hindsight BiasI knew that would happen
• Flexible attributionIm really good at
  Blackjack, I lost on the roulette because of the
  other bloke
• Absolute frequency biasI dont thinkl about the
  losses...I won loadsa money.....
• Availability bias Look how many people have won
  the lottery....loads!!

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In review....

• Components of addiction....Check
• Models of addiction....Check
• Biological/Cognitive.....Check
• A little of behavioural too....a little check!
• Evaluation of two models...Check

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Try these questions to check your understanding
so far...in pairs on whiteboards..10 mins.

• What are heuristics why do they helps us
  understand addictive behaviour?
• Outline three criticisms of biological approach o
  addictive behaviour?
• Outline three criticisms of cognitive approach to
  addictive behaviour