Observational Learning - Bobo Doll Experiment

·      Often called ‘modelling’

·      Observational learning occurs when someone uses their observations of another person’s actions to guide their future actions.

·      The person who you are observing is referred to as the ‘model’

Vicarious Conditioning

This occurs when an individual watches another person displaying behaviour that is either reinforced or punished, and then subsequently behaves in the same way, or a slightly modified way, or they may refrain from a certain behaviour due to what they have observed.

EXAMPLE: Mr Tippet – How I thought that I was in love with Mr Tippet, my grade 2 teacher and I had seen on television how a girl got a guy to fall in love with her by swinging her hips and fluttering her eyelashes. SO I thought that if I imitated this behaviour it would get Mr Tippet to propose to me. So I did. I swung my hips and fluttered my eyelashes (In a slightly modified way). Needless to say, it did not work.

Vicarious Reinforcement

When a model’s behaviour is reinforced, this increases the likelihood that the observer will behave in a similar way.

EXAMPLE: If you see a student in class get reinforced with praise or a reward when they help the teacher clean the whiteboard at the end of the day, this will increase the LIKELIHOOD that you will behave in similar way in the future.

Vicarious Punishment

When the model is punished for a certain behaviour, the likelihood of the observer performing that behaviour is decreased.

EXAMPLE: If you see a student get a detention for swearing at another student in class, this will decrease the likelihood that you perform that behaviour in the future.

Albert Bandura – Bobo Doll Experiment

AIM: To see if children who saw a model behave aggressively would be more likely to imitate that behaviour.

AIM: To see if the behaviour had been learnt, even though the children did not imitate the behaviour.

Participants:

·      72 children (Stanford University nursery school)

·      36 boys & 36 girls

·      Age range 3 years – 5  ½ years

·      Mean age  4 ½ years

There were three conditions:

24 children in each condition.

12 males and 12 females.

In ALL three conditions the participants saw a film of a model beating and yelling at a blow up clown (Bobo).

However all three conditions had a different ending to the film….

Condition One:

The aggressive model was rewarded with lollies, soft drink and praise by another adult.

Condition Two:

The aggressive model was punished with a spanking and verbal criticisms such as:

‘Hey there you big bully! Quit picking on that clown!’

Condition Three:

The model was neither rewarded or punished.

WHAT HAPPENED NEXT:

Each child was placed in a room with a Bobo doll by themselves.

They were monitored behind two-way glass.

In each condition (rewarded/punished/no consequence) half of the participants were offered a reward for imitating the aggressive behaviour.

WHAT THEY FOUND:

·      Children who were offered a reward for imitating the behaviour were more likely to act aggressively and imitate the models behaviour (even those who saw the model getting punished).

·      Learning can occur regardless of whether the model is punished or rewarded.

·      The differences in aggressive behaviours was very small when the offer of a reward was made.

·      Suggests that learning may have taken place even though the observer did not imitate the aggressive behaviour (performance).

·      This can be seen by how the children were more likely to act aggressively when offered a reward.

·      Some children did not show that they have learnt the behaviour until they were offered a reward.

DIFFERENCES BETWEEN THE GENDERS:

Males were more likely to act aggressively across all conditions, even when they were in the condition in which the model was punished.

HOWEVER, when the children were offered rewards of juice and stickers (in all conditions), the females all showed an increase in aggressive behaviours IN ALL CONDITIONS. 

Key Processes in Operant Conditioning Summary

Acquisition: This refers to the establishment of a response through reinforcement.

THINK – When Skinner’s rat is first placed in the box, when it first starts hitting the lever it is accidental. During the acquisition phase, the rat is learning the appropriate response in order to receive reinforcement.

·      The speed at which the establishment occurs depends on whether continuous (constant reinforcement for every response) or partial (fixed-interval, fixed-ratio, etc) reinforcement.

Complex Behaviours (Such as training a pigeon to turn around):

When complex behaviours are required to learnt, SHAPING is used.

Shaping: Refers to a procedure in which reinforcement is given for any response that ultimately leads to the final desired response or target behaviour (Also known as the method of successive approximations).

EXAMPLE: When training the pigeon to turn around in a circle, Skinner first started reinforcing the pigeon whenever it took a step to the left. It would reinforce this behaviour until the pigeon had associated the behaviour with being reinforced, then he would cease reinforcement. The pigeon would then happen to turn slightly more to the left and then the reinforcement would begin again for that behaviour. This process would continue until the pigeon had turn in a full circle.

Extinction: Is the gradual decrease in the strength or rate of a conditioned response (learned response) following consistent non-reinforcement of the response.

SO – in other words, Skinner would stop reinforcing the rat or the pigeon for its response, and eventually the strength or rate of that response would decrease.

·      Extinction is less likely to occur when partial reinforcement is used. WHY? Because when continuous reinforcement is used, the organism is used to being reinforced for every single correct response, and when it stops getting reinforced for correct responses the behaviour will extinguish very quickly. Partial reinforcement is more resistant to extinguish because the organism is used to making correct responses without getting reinforced, so they can hold out for longer.

·      WHICH IS THE MOST RESISTANT TO EXTINCTION? Variable-Ratio schedule of reinforcement (Think Pokie machines – people will continue to play even thought they rarely get reinforced).

Spontaneous Recovery: Once the response appears to be extinct, the organism will once again show the response in the absence of reinforcement.

EXAMPLE: The pigeon could turn around in a circle again or the rat could push down on the lever again, even though this behaviour/response had been extinguished due to the absence of a reinforcer.

Stimulus Generalisation: This occurs when the correct response is made to another stimulus that is similar to the stimulus that was present when the conditioned response was reinforced.

EXAMPLE: Skinner operantly conditioned rats to press a lever for a reinforcer (food) every time that a light flashed in the Skinner Box. This light could be a variety of colours which flashed at various times. The rat could show stimulus generalisation by pressing the lever for reinforcement whenever any coloured light was flashed.

Stimulus Discrimination: This occurs when an organism makes the correct response to a stimulus and is reinforced, but does not respond to any other stimulus, even when the stimuli are similar.

EXAMPLE: With the rats pressing for reinforcement when lights are flashed, stimulus discrimination could occur if the rat only pressed the lever for reinforcement whenever the ‘red’ light, or a specific colour was flashed and would not respond when other coloured lights were flashed. Skinner was able to do this deliberately by only providing reinforcements when a certain coloured light was flashed.

Examples of Reinforcement/Punishment

Operant Conditioning

•Operant conditioning - the learning of voluntary behavior through the effects of pleasant and unpleasant consequences to responses.

The study of how behavior is affected by its consequences.

•Investigates the learning of voluntary responses.

•Reinforcement - any event or stimulus, that when following a response, increases the probability that the response will occur again.

•Reinforcer – Any object or event that changes the probability that an operant behaviour will occur again.

•Positive reinforcement - the reinforcement of a response by the addition or experiencing of a pleasurable stimulus.

•Negative reinforcement - the reinforcement of a response by the removal, escape from, or avoidance of an unpleasant stimulus.

Example: Taking aspirin for a headache is negatively reinforced – removal of headache!

Schedules of Reinforcement: Refers to the frequency and manner in which a desired response is reinforced.

•Partial reinforcement effect - the tendency for a response that is reinforced after some, but not all, correct responses to be very resistant to extinction.

•Continuous reinforcement - the reinforcement of each and every correct response.

Four Main Schedules of Partial Reinforcement

TERMS YOU NEED TO KNOW:

Fixed: Always the same

Ratio: Number of responses

Interval: Time

Variable: Always different

•Fixed ratio schedule of reinforcement - schedule of reinforcement in which the number of responses required for reinforcement is always the same.

Eg: Getting paid for every 10 strawberries picked.

•Variable ratio schedule of reinforcement - schedule of reinforcement in which the number of responses required for reinforcement is different for each trial or event.

Eg. Poker machines

•Fixed interval schedule - of reinforcement schedule of reinforcement in which the interval of time that must pass before reinforcement becomes possible is always the same.

Eg. Pedestrian crossing

•Variable interval schedule of reinforcement - schedule of reinforcement in which the interval of time that must pass before reinforcement becomes possible is different for each trial or event.

Eg. Fishing

Punishment: is the delivery of an unpleasant stimulus following a response, or the removal of a pleasant stimulus following a response.

When closely associated with a response, punishment weakens the response, or decreases the chance of that response occurring again over time.