a) Pavlov’s experiments on classical conditioning of the dog brought to light several principles useful in the understanding of habit formation. These include reinforcement, extinction, spontaneous recovery, generalization, and discrimination.
b) Skinner’s experiments on operant conditioning have extended conditioning principles to kinds of responses that cannot be elicited by recognized unconditioned stimuli. Operant behaviour acts upon the environment to produce or gain access to reinforcement and becomes strengthened by reinforcement.
c) Rate of responding is a useful measure of operant strength. Partial reinforcement illustrates the orderliness of operant behaviour, since long and regular runs of responses can be sustained by occasional reinforcement. Secondly reinforcement, the fact that a stimulus associated with a reinforcing stimulus acquires reinforcing properties, increases the possible range of conditioning and explains the reward value of such incentives as social approval and money.