Classical conditioning explains why a sound makes you flinch. It cannot explain why you keep doing something. For that you need consequences — and one small grid that sorts out the four terms students most often scramble.
📘 What you need to know
Operant conditioning (OC) is learning through consequences, the second core assumption of behaviourism.
Where CC is about stimulus and response, OC is about reward and reinforcement.
Reinforcers increase the likelihood a behaviour is repeated; punishers decrease it; neutral operants do neither.
Positive means something is added. Negative means something is removed. Neither means “good” or “bad”.
Behaviour can also be repeated purely to avoid an unpleasant consequence.
Skinner (1953) and the Skinner Box are the key research.
Evaluation words: reliability, falsifiability, environmental reductionism, the 3 Rs.
The grid that fixes the four terms
Nearly every mark lost here comes from mixing up negative reinforcement with punishment. They are opposites. Ask two questions: is something being added or removed, and does the behaviour go up or down?
Look at the diagonal. Both green cells increase behaviour even though one adds and one removes — which is exactly why negative reinforcement is not punishment.
Definition to learn
Operant conditioning = learning in which the consequences of a behaviour determine how likely that behaviour is to be repeated.
Test yourself with one sentence: “I do my homework so I do not get a detention.” Nothing was added. Something unpleasant was avoided. The behaviour went up. That is negative reinforcement, every time.
Key study: Skinner (1953)
Skinner argued that learning is an active process: organisms operate on their environment and are shaped by what happens next. To test it he built a controlled chamber, usually used with rats or pigeons.
The same box tested all three conditions. Changing only what followed the lever press is what makes it a controlled study of consequences.
Condition
What happened when the lever was pressed
What the rats learned
Positive reinforcement
A hungry rat pressed the lever accidentally and received a food pellet
Lever-pressing increased; rats soon pressed immediately on being placed in the box
Negative reinforcement: escape
A mild electric current running through the floor was turned off
Rats learned to press quickly to escape the shock
Negative reinforcement: avoidance
A light signalled that a shock was coming (a discriminative stimulus)
Rats learned to press when the light came on, avoiding the shock altogether
The conclusion in one line. Both adding something pleasant and removing something unpleasant strengthen behaviour. That single sentence is the finding of all three conditions.
Evaluating operant conditioning
Strengths
Explains the maintenance of phobias. Someone with social phobia avoids events involving people. Avoidance is negative reinforcement — each time it is repeated the person is rewarded with relief and security, so the phobia is maintained.
High reliability. Standardised procedures in controlled conditions can be repeated, and the theory satisfies falsifiability, so it can be tested scientifically.
Wide application. Token economies, classroom behaviour management and animal training all run on these principles.
Limitations
Cannot explain damaging repeated behaviour. People who self-harm may do so for the relief it brings, and people continue smoking despite disliking the taste and smell. Neither fits the model’s account of reinforcement.
Environmental reductionism. Humans are more complex than rats and operate at a higher cognitive level, with mechanisms such as self-efficacy that behaviourism does not credit.
Animal research. Generalising from a rat in a box to a person in a life is a genuine leap.
Link to concepts
Responsibility — by today’s standards Skinner’s work raises real ethical concerns. Keeping animals in conditions where they are repeatedly shocked may be judged unnecessarily cruel. Researchers should follow the 3 Rs: Reduce (fewer animals), Replace (use alternatives) and Refine (minimise suffering).
Perspective — OC predicts people escape harm when they can. Yet some people offered a chance to escape a harmful situation do not take it. Some victims of domestic abuse remain in a dangerous situation even where leaving is possible. Learned helplessness explains this better: repeated exposure teaches a person that they have no power to change things, even when a chance appears.
Exam practice
WORKED EXAMPLE
Explain negative reinforcement with an example. [3 marks]
1. Define
Negative reinforcement is performing a behaviour to remove or avoid something unpleasant, which makes the behaviour more likely.
2. Give the study exampleSkinner’s rats pressed the lever to switch off a mild current, and pressing increased.
3. Give a human example
A student completes homework to avoid a detention.
Define + animal example + human exampleSay explicitly that the behaviour increases. That word separates it from punishment.
WORKED EXAMPLE
Discuss ethical considerations in animal research. [ERQ paragraph]
Issue
Skinner delivered mild electric shocks to rats over repeated trials.
Judge it against standardsBy today’s guidelines this could be seen as unnecessary suffering, since the same principle was already shown by the food condition.
Give the framework
Modern researchers apply the 3 Rs: reduce, replace, refine.
Balance
The findings underpin real treatments, so the value was high — but value does not automatically justify the cost.
Value earned, cost still realNaming the 3 Rs turns a vague ethical complaint into a proper answer.
💡 Exam tip
Draw the 2 × 2 grid in the margin before you start writing. It takes ten seconds and prevents the classic error.
Give one animal and one human example for each term. Examiners want to see transfer.
Use avoidance and phobia maintenance as your application — it links straight back to classical conditioning.
Say the reinforcer is the consequence, not the behaviour. Skinner is precise about this.
Compare with CC in one sentence: CC pairs two stimuli, OC pairs a behaviour with its consequence.
Learned helplessness is your best evaluation point for questions on limitations.
⚠️ Common mix-up
Negative reinforcement is not punishment. It increases behaviour. This is the single most common error in the topic.
Positive does not mean nice. Positive punishment adds something unpleasant.
A detention is positive punishment, because something is added.
Neutral operants exist. Some consequences change nothing — worth one mark if a question asks for all three types.
Skinner did not invent conditioning. He built on it — Pavlov came first, with a different mechanism.
Do not call the Skinner box an observation. It is a controlled experiment.
Up next: The Dual Process Model of Thinking — back to thinking, and a model that explains why the same person can be brilliantly logical and completely impulsive within the same hour.
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