Learning much more active than in classical conditioning
Based on work of Thorndike
Learning a behaviour because of its consequences
Consequences are rewarding or punishing
Make behaviour more or less likely
Positive/negative reinforcement
Positive/negative punishment
Skinner (1904-1990)
Radical behaviourism: should only use scientific methods to study
human and animal behaviour
All behaviour learned from consequences, called this operant conditioning
His focus was on effects of emitted behaviour rather than Pavlov's focus on
the elicited behaviours themselves
1938, placed pigeon in Skinner box.
Pecking at lever would lead to food being delivered
Pecked randomly at first and accidentally pecked lever
stimulus - S - and received reward - R.
Reward was reinforcement, which stamped-in rewarded behaviour
Unrewarded behaviour stamped out
Behaviour brought under stimulus control
Stronger reinforcement = more stamping in
If pigeon also learns to get food by pecking at a button when it is lit up it is learning
to discriminate between states of illumination (a discriminative simulus)
Hungry rat in box: inside box was lever
which would dispense food when pressed
Rat first had to learn this lever-pressing behaviour, so food dispensed every time it
approached the lever at first
When rat pressed lever food was dispensed
Rat then kept pressing lever to get food (reward
Behaviour positively reinforced
Skinner described OC in terms of ABC
Antecedents: situation beforehand
Behaviour: what the animal does
Consequences: the probability of a behaviour being repeated
depends on strengthening or weakening S-R links
Most human behaviour relies not on primary reinforcers (food,
water etc.) but on secondary reinforcers (money, tokens, career
success, etc.)
Secondary reinforcer is neutral stimulus that acquires reinforcing properties because it can be
linked with a primary reinforcer (e.g. exchanging money for food)
Principles applied to many areas, e.g. education, prisons and psychiatric institutions
Used to modify speech in autistic children
When a child has under-developed speech, therapist uses a
behaviour-shaping technique
When child begins to imitate therapist's speech/behaviour, s/he receives praise
as a reward - a positive reinforcer
Continues until child can use words independently and without prompting