- Identify the unconditioned and conditioned stimuli and responses in examples of classical conditioning
- Distinguish positive and negative reinforcement and punishment
- Compare schedules of reinforcement
- Explain observational learning (Bandura)
Your phone vibrates and you reach for it without thinking. A song reminds you of a summer holiday on the Caspian coast. A dog runs to the kitchen when it hears the fridge door. None of these reactions is innate — they were all learned. In psychology, learning is a relatively lasting change in behaviour or knowledge that comes from experience.
Classical conditioning: Pavlov
The Russian physiologist Ivan Pavlov received the Nobel Prize in 1904 for his research on digestion. While studying saliva in dogs, he noticed that the dogs began to salivate before the food arrived — when they saw the lab assistant or heard footsteps. Pavlov repeatedly paired a neutral sound with food, and after a while the sound alone made the dogs salivate. A conditioned reflex had formed.
- NSneutral stimulus — causes no response at first (a sound)
- USunconditioned stimulus — triggers a natural response (food)
- URunconditioned response — an innate reaction (salivating to food)
- CSconditioned stimulus — the former neutral stimulus that has become a signal
- CRconditioned response — a learned reaction (salivating to the sound)
Left: pairing during learning. Right: the result after learning.
If the conditioned stimulus is given many times without food, the response weakens — this is extinction. After a pause the response may briefly return (spontaneous recovery). If similar sounds also trigger it, that is generalisation; responding only to one particular sound is discrimination. Classical conditioning helps explain phobias, advertising (linking a product with pleasant music or famous faces) and the disgust we can feel for a food after food poisoning.
Operant conditioning: Thorndike and Skinner
In 1898 Edward Thorndike put cats into “puzzle boxes”: when a cat escaped by accidentally pressing a lever, it did so faster the next time. He proposed the law of effect: behaviour followed by a satisfying result becomes more likely. B. F. Skinner developed this idea into operant conditioning: behaviour is shaped by its consequences. In the “Skinner box” a rat pressed a lever to get food and soon pressed it more and more often.
| Something is added (+) | Something is removed (−) | |
|---|---|---|
| Behaviour increases → reinforcement | Positive reinforcement: praise for doing homework | Negative reinforcement: the annoying seatbelt beep stops when you buckle up |
| Behaviour decreases → punishment | Positive punishment: extra chores for being late | Negative punishment: losing the phone for a day |
How persistent a behaviour becomes depends on the schedule of reinforcement. A reward every time (continuous reinforcement) gives fast learning, but the behaviour dies out quickly when rewards stop. Fixed ratio: a free coffee after every 10 purchases. Variable ratio: slot machines — the reward comes after an unpredictable number of tries, and behaviour is the most persistent. Fixed interval: a monthly salary, or studying just before a scheduled test. Variable interval: checking your phone because you never know when a new message will arrive. Complex behaviours are taught by shaping — reinforcing steps that come closer and closer to the goal.
Learning by watching: Bandura
We do not learn everything by being rewarded or punished ourselves. In 1961 Albert Bandura showed that children who watched an adult hit an inflatable “Bobo” doll were later more likely to copy those aggressive acts. Observational learning needs four things: attention, retention (remembering), the ability to reproduce the action, and motivation. Children learn this way from parents, teenagers from friends and videos — and the same mechanism helps you pick up a new skill from a tutorial video.
- 1898Thorndike: puzzle boxes and the law of effect
- 1904Pavlov receives the Nobel Prize
The prize was for his work on the physiology of digestion.
- 1913Watson announces behaviourism
- 1920The “Little Albert” experiment
It showed that fear in humans can be conditioned.
- 1938Skinner, The Behavior of Organisms
- 1961Bandura's Bobo doll experiment
Name the type of learning in each situation.
a) Murad's sister used to cry at the dentist; now she starts crying as soon as she smells the clinic.
b) Elvin gets 10 extra minutes of gaming when he finishes his homework — now he does homework faster.
c) Aysel's parents stop nagging when she tidies her room — she tidies it more often.
d) Leyla loses her phone for a day after being rude — she is rude less often.
Show solutionHide solution
b) Positive reinforcement: something pleasant is added and the behaviour increases.
c) Negative reinforcement: something unpleasant (nagging) is removed and the behaviour increases.
d) Negative punishment: something pleasant (the phone) is taken away and the behaviour decreases.
- 1.In Pavlov's experiments, food was the stimulus.
- 2.When the sound is repeatedly given without food, the response fades: this is .
- 3.Removing something unpleasant to increase a behaviour is reinforcement.
- 4.Rewarding steps that come closer and closer to a goal is called .
- 5.Slot machines reward players on a variable- schedule.
- 6.Bandura showed that children learn aggression by adults.
Key points
- Learning is a relatively lasting change in behaviour that comes from experience.
- Classical conditioning: a neutral stimulus paired with an unconditioned stimulus comes to trigger a conditioned response (Pavlov).
- Operant conditioning: behaviour is shaped by its consequences (Thorndike, Skinner).
- Reinforcement increases behaviour and punishment decreases it; positive means adding, negative means removing.
- Variable-ratio schedules create the most persistent behaviour; observational learning needs no direct reward.
Check yourself
10 questions. Every correct answer earns XP.