Biological Approach to Smoking- Initiation
- Special neurons in the reward pathway release dopamine (VTA), which give you a sense of pleasure (NA).
- Your memory tells you that a particular behaviour will make you feel good.
- This reward pathway may be reinforced up to 20 times per cigarette.
- Some poeple may respond more to nicotine or be prone to develop addcitive personalities or physiological dependency for genetic reasons.
Commings et al:
- Increased incidents of the A1 variation of the DRD2 gene among smokers and ex-smokers. (A1 varient of gene= fewer dopamine receptors in the brain).
- Men with A1 varient also started smoking earlier and had shorter periods of abstinence from smoking.
Biological Approach to Smoking- Maintenance
Thorgeirsson et al:
- 500,000 Icelanders
- In their sample, a pattern of gene variation at two points of chromosone 15.
- In their sample, the genetic variant had an affect on the number of cigarettes smoked per day.
Schachter et al:
- The Nicotine-titration model suggests smokers smoke to maintain a certain level of nicotine in their system.
Nicotine can induce change in the structure and function of the reward systems neurons.
These changes contribute to tolerance, dependence and craving.
Stimulation of brain areas collectively produces pleasure and reinforcement of that behaviour.
Biological Approach to Smoking- Relapse
- The VTA- NA pathways also link to other areas of the brain including the memory areas and help make addicts highly sensitive to reminders of past highs, vulnerable to relapse when stressed and unable to control the urge to repeat the addictive behaviour.
- A period of abstinence, followed by just a small amount of nicotine means that an individual will experience a high even greater than that of a first time smoker.
- Nicotine withdrawal is associated with increased irritabiltiy and weight gain.
Biological Approach to Gambling- Initiation
- Special neurons in the reward pathway release the chemical dopamine, which gives you a sense of pleasure (NA).
- Your memory tells you that a particular behaviour will make you feel good; the brain tells the brain to initiate the behaviour.
- Gamblers are more likely to have lower levels of dopamine receptors in the VTA areas of the brains (due to the A1 varient of the DRD2 gene).
- Require increase stimulation of this area to reach a normal level of excitement.
Biological Approach to Gambling- Initiation
Black et al:
- First degree relatives more likely to gamble.
Shah et al:
- Evidence of genetic factors in gambling in men.
- Gamblers are high sensation seekers with lower risk of arousal.
- Poor tolerance of boredom linked to pathological gambling.
Biological Approach to Gambling- Maintenance
Shinohara et al:
- Found that raised levels of dopamine and noradrenline occur in social gamblers not only when they're gambling, but occur in anticipation of gambling and in response to gambling paraphernalia in pathological gamblers.
Reuter et al:
- Gambling addicts show less activation in the medial forebrain pleasure circuit during winning than non-gamblers.
- Continued overproduction of dopamine leads to desensitisation in receptors to compensate.
- Gamblers want it more but experience less pleasure from a win. This leads to increased desire to engage in the addictive behaviour to get the same dopamine high.
- Gambling addicts more likely to see a near miss as a near win.
Biological Approach to Gambling - Relapse
- The VTA - NA pathways link to other areas of the brain including the memory areas and help make addicts highly sensitive to reminders of past highs.
- Gamblers miss the physiological/psychological rewards of stress reduction or excitement associated with gambling.
Behavioural Approach to Smoking- Initiation
- unconditioned stimulus (friends) spontaneously produces an unconditioned response (relaxed)
- US is associated with a conditioned stimulus (smoking) will produce conditioned response (relaxed).
- Learn that smoking can produce the same reward as the original stimulus
Social Learning Theory:
- learning smoking through observation of influential role models
- they form mental representations of smoking and rewards
- form vicarious reinforments of getting rewards (friends)
- self efficacy expectations of how well they can repeat the same behaviour to get the same rewards.
Behavioural Approach to Smoking- Maintenance
- short term pleasure from drugs (nicotine) provides more immediate positive reinforcement (rewards) than longer term effects (punishment)
- avoid unpleasant withdrawal symptoms is a potent source of negative reinforcement for continued drug taking
- withdrawal effects act to maintain addictions through negative reinforcement of avoidance of the unpleasant stimuli
-"doing something to avoid the negative consequences"
Behavioural Approach to Smoking- Relapse
Cue Reactivity Theory:
- presented with a variety of cues associated with their problems behaviour, addicts show a pattern of physiological and behavioural repsonses
- addicts react to things associated with their addiction in similar ways to how they react to the object of the addictive behaviour
- smokers see a lighter and want to start smoking again
- patients who had been treated for drug addiction experienced withdrawal like symptoms if they returned to places associated with their addiction
Behavioural Approach to Gambling- Initiation
- unconditioned stimulus (friends) spontaneously produces and unconditioned response (excitement)
- US is associated with a conditioned stimulus (gambling) and produce conditioned response (excitement)