Learning theories of Addiction Flashcards
What are habits?
- Mechanisms that don’t require conscious
- Impulse to engage in habits is stronger than desire to restrain
How are habitual behavioural patterns developed?
-Developed independently of conscious evaluation of pros and cons
What is operant conditioning?
- The punishment or reward following you doing something
- Learning by consequences
What are the two factors behind operant conditioning?
- Positive reinforcement
- Negative reinforcement
What is positive reinforcement?
- Increases probability of a behaviour occurring by presentation of reward
- Behaviour (take drug): Reward (get high)
What is negative reinforcement?
- Increases probability of a behavior by removing discomfort
- Stimulus (withdrawal, depression): Response (take drug)
When does the most effective reinforcement occur?
-After a behaviour
What type of drugs are most addictive and why is this the case?
- Intravenous drugs
- Smoking or Heroin
- Almost instant effects
- Reward is felt immediately
What is intermittent reinforcement?
- reinforcement does not occur every time
- ratio or schedule of reinforcement
How do animals utilise reinforcement?
-Learn avoid and escape comfort
What are cues aka?
- Discriminative stimuli
- Tie in well with classical conditioning
What is the strength of learning determined by?
- Nature of the reinforcer
- The schedule of reinforcement
- For how long the schedule is in place
What chemical and pathway underpins this reinforcement of learning?
-Dopamine in the meso-limbic pathway
Which areas of brain release dopamine?
-VTA and NA
Is dopamine release the same for all scenarios?
- No
- Brain titrates the release of dopamine depending on situation
- Hence why you feel happier for certain stimuli over others
fav sandwhich vs winning lottery
What are the three components of the mesolimbic dopaminergic pathway?
- ventral midbrain
- via medial forebrain bundle
- to limbic region
What is role of limbic system and what are the components?
- emotional responses
- forebrain (amygdala, NA, striatum)
What effect do dependence based drugs have on dopamine release?
-increase dopamine in the nucleus accumbens
What is cocaine and what does this mean?
- dopamine reuptake inhibitor
- prevents reuptake of dopamine
- so synaptic conc stays high
- extended highs
What type of transmitter is dopamine?
-monoamine
Summary drug dependence model
Experimentation
Positive reinforcement
Repeated use
Tolerance
Withdrawal
Drug Seeking (Negative Reinforcement)
Drug Dependence
What is tolerance?
- Idea that if you take same amount of drug consistently, your body reacts less over period of time
- increased threshold of reward
- requires more of drug to reach same level of pleasure
- Compensatory mechanism to maintain homeostasis
Describe brief process of classical conditioning
- Unconditioned stimulus (UCS) elicits an Unconditioned Response (UCR)
- Neutral stimulus (NS) found that doesn’t elicit UCR
- Neutral stimulus repeatedly paired with UCS
- Neutral stimulus becomes a Conditioned Stimulus (CS) that can elicit the Conditioned Response (CR)
Example of classical conditioning
- provide food (UCS), trigger salivating (UCR)
- play sound such as bell (NS)
- Food and bell paired together (NS and UCS)
- Leads to response where dog known food is there when they hear bell (CS leads to CR)
2nd clinical setting example of classical conditioning
- cancer diagnosis
- referred to nutritionist
- alternative food plan
- because chemo treatment is nauseous, can be unintentionally paired with normal meal plan
- eat same food can induce nausea even after chemo ends
What conditions in drug dependency leads to conditioning?
- Injecting equipment
- Location/Environment
- Cook-up ritual
- Psychological state
- Physical State
What can conditioned response be like?
-drug like or drug-opposite depending on the circumstances and the drug
What are two examples of drug-opposite conditioned responses?
- Conditioned withdrawal
- Conditioned tolerance
What is conditioned tolerance?
- effects of environment on tolerance
- levels of tolerance is dependent on environment
What is conditioned withdrawal?
-any conditions that occur during withdrawal
What are two examples of drug-liked conditioned euphoria?
-Conditioned euphoria (‘needle freak’ phenomenon) Placebo effects (under certain circumstances)
What is conditioned euphoria?
-show euphoria on presentation of drug or before they inject drug
What are withdrawal symptoms?
-compensatory reactions that oppose the primary effects of the drug
-Drug opposite CR can mimic withdrawal symptoms
If occur before drug they will reduce the drug effect (form of tolerance)
-These reactions can produce relapse in abstinent people, and contribute to tolerance in drug users
Drug opposite conditioned responses: conditioned withdrawal
UCS --> UCR Opioid metabolised -- Rebound activity Receptors evacuated -- (adrenergic etc) Withdrawal (signs & symptoms)
CS –> CR
Environment – Mild Withdrawal
Drug equipment –
Drug opposite conditioned response: conditioned tolerance
UCS –> UCR
Injection Homeostatic response
Drug effects counter to drug effect
CS –> CR
Cues that signal Same as above, but in
drug is about to appear the absence of the drug is perceived as drug like effects.
Why is risk of OD higher in novel environment greater?
- drug tolerance conditioned to cues in normal environment
- in novel environments won’t have the same degree of tolerance
