STUDY
B.F. Skinner:
B.F. Skinner was very much influenced by Watson's behaviourist ideas. However, he realised that Watson's psychology had its issues: A psychology based wholly on classical conditioning assumes that organisms are essentially passive - they just hang around waiting for stimuli to respond to.Skinner's important insight was that an animal's or person's behaviour was determined by the consequences of its past behaviour.
Operant Conditioning:
Skinner called learning from consequences 'Operant Conditioning' because it is based on how organisms operate in their environment. It is an explanation for voluntary behaviour. Essentially, Skinner's theory is that the likelihood of future behaviour is determined by the consequences of past behaviour. in common with Watson, Skinner didn't think it was necessary to speculate on what went on in people's minds. ALL COGNITIVE PROCESSES IRRELEVANT. He believed that the environment and behaviour were all that was necessary to an understanding of psychology.
How do the consequences of behaviour affect future behaviour?
How do the consequences of behaviour affect future behaviour?
- If behaviour has no consequence, then the likelihood of that behaviour being repeated in future does not change.
- However, if behaviour brings about a consequence that the organism (person or animal) finds pleasant, or unpleasant, then this can strengthen or weaken the behaviour accordingly.
Types of Reinforcement:
- Positive Reinforcement: a pleasant consequence encourages behaviour to be repeated (EG: training your dog to raise its paw with doggy treat rewards)
- Negative Reinforcement: removal of an unpleasant consequence encourages behaviour to be repeated (EG: tidying your room to stop parents nagging you)
- Punishment: an unpleasant consequence decreases the likelihood that behaviour is repeated (EG: you touch a hot oven and learn not to do it again)
Skinner's Research:
Skinner devised an experiment using rats (or pigeons) to demonstrate the principle of learning via operant conditioning. He designed a piece of apparatus known as the Skinner box:
- Skinner placed a hungry rat into the box and observed the rat's behaviour. Whilst exploring the environment, the rat accidentally pressed the lever and receiving food pellets (rewards), subsequently leading the rat to increase its pressing of the lever (referred to as positive reinforcement).
- Skinner then experiment with unpleasant environmental stimuli such as loud noise, which could be stopped pressing the lever (referred to as negative reinforcement).
- Skinner also experimented with the use of punishment, by delivering an electric shock to the rat when it pressed the lever (punishment). As expected, this led to a decrease in lever pressing.
- Skinner also demonstrated that learning could be extinguished. If reinforcement is no longer provided when a lever is pressed, the rat unlearns this connection between lever pressing and reward, therefore the rat stops pressing it.
Schedules of Reinforcement:
In the case of the Skinner box, if food (reinforcer) is not dispensed for every single lever press, but to a predetermined set schedule then different response patterns will emerge. Skinner experimented by using different ratio schedules eg. 1:5 a food pellet was dispensed every 5th lever press. He discovered that unpredictable reinforcement was more successful for conditioning behaviour than continuous reinforcement.
Shaping:
Another method of learning discovered by Skinner was one referred to as Shaping, a process used to teach complex behaviours (not part of an animal's repertoire). A complex behaviour is broken down into a series of simple behaviours. These are taught one by one using reinforcements and punishment and gradually combined to create the desired complex behaviour. Skinner used this process to teach his pigeons to play ping pong. Humans also learn most of their skills in this step by step manner. Shaping is important in behaviour modification, where behaviours can be learned in this simple strategic way.