Classical conditioning
Some learning happens by association: we come to expect one event after another.
Pavlov's discovery
Ivan Pavlov noticed that dogs began salivating before food arrived. Food is an unconditioned stimulus (UCS) that naturally causes salivation, an unconditioned response (UCR). When a neutral stimulus, like a tone, is repeatedly paired with food, it becomes a conditioned stimulus (CS) that alone triggers salivation, now a conditioned response (CR).
Acquisition, extinction, and recovery
Acquisition is the period when the association is learned. If the CS is repeatedly presented without the UCS, the response weakens: extinction. After a rest, the response may briefly reappear, called spontaneous recovery. Stimulus generalisation means similar stimuli also trigger the response; discrimination means learning to respond only to the specific CS.
Conditioning in everyday life
John Watson's 'Little Albert' study conditioned a baby to fear a white rat by pairing it with a loud noise, a study now seen as unethical. Classical conditioning helps explain phobias, food aversions after illness, and why advertisers pair products with pleasant images and music.
Flashcard
A stimulus that naturally triggers a response
Check your understanding
A child feels nauseated after eating a certain food while sick and now feels queasy at the sight of that food. The food has become a: