Models Of Addiction- Biological Approach

Front 1

Initiation

Back 1

Inherit a genetic predisposition to develop an additiok

Multiple genes -focus on A1 variant of DRD2 gene -involved in regulation of dopamine levels

May increase sensitivity to action of dopamine

SLC6A3-9 ( responsible for removing dopanime from synapse)

Front 2

Maintenance

Back 2

The meso limbic dopamine system which is concerned with memory, reward and motivational processes- is involved with maintanence

In normal activity, cells in the meso limbic system releases dopamine into the synapse, addictive substances and behaviours increases dopamine levels

Addicts continue with their addiction in order to experience hights at increasing dopamine levels due to developing tolerances.

Falling levels lead to withdrawal symptoms

Front 3

Relapse

Back 3

Substances ( nicotine ) activate dopamine reward pathways which causes the brain to adapt to the new levels ( neuroadaptation )

Adaptation not needed whrn substance isnt there so withdrawal symptoms could be experienced that are unpleasant

Front 4

Evaluation comparing to other approachs

Back 4

Doesnt explain initiation as well as the behavioural or cognitive approach

Front 5

Evaluation - led to effective treatment

Back 5

Such as nicotine replacement therapy for smoking

Front 6

Evaluation absolves addicts of responsibility

Back 6

If the causes of addiction are due to genes or dopamine levels, this relieves the addict of taking responsibility for their addiction and makes it less likely that treatment will be successful

Front 7

Evaluation- best explanation-biopsychosocial model

Back 7

Involving an interaction of factors

- biological vulnerability involving the brains reward systems

-family/ peer attitudes that support addictive behaviour

-high levels of impulsivity / cognitive distortions

Front 8

Application to smoking -initiation

Back 8

A meta analysis by thorgeirsson et al analysed data from 140,000 people and have discovered that there are DNA variants associated with whether people start smoking, it is convincing evidence due to large sample size

Front 9

Initiation application to smoking, however

Back 9

The stufy shows a correlation between starting smoking and genetic not causation. It is likely that genetics only lead to a predisposition to become dependent

An environmental trigger e.g. peer influence is needed to start the addiction

Front 10

Application to smoking -maintenance

Back 10

Schachter conducted a double blind study with adult smokers. Over a 4 week period ppts alternated between smoking high and low nicotine cigarettes. They smoked low nicotine cigarettrs for a week and high nicotine cigarettes the next. As the model predicts the subjects smoked more low than high nicotine cigarettes. This effect was especially strong for heavy smokers, who smoked 25% more of the low than high nicotine cigarettes

Front 11

Application to smoking -relapse

Back 11

Lerman tested smokers when they had abstained from smoking for one night and found increased blood flow to the parts of the brain associated with memory, reward and learning showing that these parts of the brain do become particularly active when a person is craving a cigarette

Front 12

Application to gambling - initiation

Back 12

Slutske looked at concordace rates of MZ and DZ twins in relation to gambling addiction. She studied nearly 5000 individuals and found that the concordance rate was twice as high for MZ twins as for DZ twins

Front 13

Application to gambling- maintenance

Back 13

Chase and clark studied 24 regular gamblers. They completed a computerized gambling gamr based on slot machines whilst their mid brains were scanned using fMRI. Increased activity in the mesolimbic system resulted from wins but crucially also from near missed. In addiction the higher the level of gambling severity the greater the response recorded

Front 14

Application to gambling - relapse

Back 14

Stopping gambling results in the same kind of withdrawal symptoms associated with stopping drugs

Front 15

Application to gambling - relapse - wray and dickerson

Back 15

Found 60% of pathological gamblers reported physical side effects during withdrawal and these were sometimes more severe than those reported by a comparison group during withdrawal