Lecture 7 - Learning in humans

Question 1

Why do people have a craving for drugs?

Answer 1

• smokers often report reduced desire to smoke where smoking is forbidden
• craving for drugs can be the result of conditioning
• the CS is the taste of the cigarette, the US is the absorption of nicotine into the bloodstream
• this absorption evokes a pleasurable UR for the smoker
• following sufficient pairings the CR also evokes pleasure
• to encourage the smoker to quit smoking we want to prevent the CR from occurring

Question 2

What are the 3 ways to stop smoking?

Answer 2

1. abstinence (will-power)
   - unlikely to work as the CS-US pairing is not broken by abstinence and it only takes one or 2 experiences to relapse
2. extinction
   - we could arrange it so that the cigarette tasted the same but contained no nicotine
   - this would prevent the US from occurring and the CR would go into extinction
   - this treatment is likely to be unsuccessful, because it is likely that the smoker will be exposed to nicotine in the future and the CR will recover
3. counterconditioning
   - is the basis of aversion therapy
   - the CR is not extinguished but is replaced with another CR

Question 3

What is a phobia?

Answer 3

an irrational fear of an ‘objectively harmless’ stimulus

Question 4

Conditioning and phobias?

Answer 4

• Sometimes the direct CS e.g. a dentists drill is not the main phobic stimulus but other things associated with the drill such as the dentists chair or waiting room
• Even without direct experience of a traumatic US or pain-causing CS, humans could form an association via vicarious conditioning even if the UR is evoked via story-telling

Question 5

How to treat phobias - Jones 1924?

Answer 5

• first person to develop behavioural therapy
• used baby Peter
• had a fear of rats and rabbits
• tried ‘modelling’ at first - observing others interacting happily with rats and rabbits
• developed a programme of desensitisation

Question 6

How to treat phobias - Systematic desensitisation - Wolpe & Lazarus?

Answer 6

• therapist performs structured interviews with the patient to get a list of cues associated with anxiety and will rank them in order of their likelihood to evoke anxiety
• relaxation paired with anxiety cues
• new association with relaxation reduced effectiveness of cues
• ethical issues especially when using flooding so some therapists have turned to VR

Question 7

Skinner and reinforcers?

Answer 7

• Primary reinforcers = those that need no experience to be effective
• Access to food, water, and sex have all been used as primary reinforcers
• Reinforcers are important for changing an animals behaviour

Question 8

Premack principle?

Answer 8

• Preferred activities can act as reinforcers for less preferred activities
• Homme et al (1963):
  -> used the Premack principle to reinforce good behaviour in nursery children using creative activities that the children preferred to engage in

Question 9

Secondary/ conditioned reinforcers?

Answer 9

• Some reinforcers aren’t effective from birth, their value has to be learned = secondary or conditioned reinforcers
• e.g. = money

Question 10

Social reinforcers?

Answer 10

• social reinforcement = category of both primary and secondary reinforcers
• Allen et al 1964:
  -> studied a nursery school child who engaged in odd behaviour and would only talk to adults
  -> he instructed teachers to only give her attention when playing with other children
  -> within a day her contact with children went from 10 to 60%

Question 11

Delay of reinforcement?

Answer 11

• Can change the likelihood of producing a particular behaviour
• Rachlin and Green (1972):
  -> pigeons could choose one response to give immediate access to grain for a short time, a different response for longer access, but only after a delay
  -> Choosing the response that led to a delay would result in getting access to food for twice as long as the immediate reinforcer
  -> Despite this, the pigeons chose the response associated with the smaller reward on 95% of occasions

Question 12

Token economy?

Answer 12

• If children behave in class the token (conditioned reinforcer) can be delivered immediately
• Can be exchanged for a wide range of primary reinforcers so different children can be reinforced differently

Question 13

Fox, Hopkins and Anger 1987?

Answer 13

• Reduction of injuries in mine workers using token economy
• 12 year period, injuries fell by 68% and 85%
• Cost of injuries per year $260k
• Cost of tokens $12k
• Unions insisted on writing tokens into contracts