What the exam asks
- Scenario classification: Identifying whether a consequence is positive or negative reinforcement or punishment, and specifying the reinforcement schedule.
- Graph interpretation: Reading cumulative recorder graphs (e.g., identifying the scalloped curve of a fixed-interval schedule or the steep slope of a variable-ratio schedule).
- Concept application: Explaining how shaping, superstitious behavior, instinctive drift, or learned helplessness operates in research studies or everyday life.
Core ideas
The law of effect and operant conditioning
While classical conditioning pairs involuntary responses with stimuli that precede them, operant conditioning (championed by B. F. Skinner) associates voluntary behaviors with the consequences that follow them. It builds on Edward Thorndike’s law of effect: behaviors followed by favorable consequences become more likely to recur, while behaviors followed by unfavorable consequences become less likely.
Reinforcement and punishment
In operant terminology, words have strict mathematical meanings:
- Reinforcement always increases the frequency of a target behavior; punishment always decreases it.
- Positive () means adding a stimulus; negative () means removing (or avoiding) a stimulus.
| Consequence type | Action with stimulus | Effect on future behavior | Classic example |
|---|---|---|---|
| Positive reinforcement | Add desirable () | Increases () | Giving a dog a treat for sitting |
| Negative reinforcement | Remove aversive () | Increases () | Taking aspirin to stop a headache (aspirin-taking increases) |
Primary reinforcers are innately satisfying and fulfill biological needs (food, water, relief from pain). Secondary (conditioned) reinforcers gain power through learned association with primary reinforcers (money, grades, praise, tokens).
Shaping, discrimination, and biological limits
- Shaping: Guiding behavior toward a complex goal by reinforcing successive approximations—small steps that get progressively closer to the desired behavior.
- Stimulus discrimination and generalization: In operant conditioning, a discriminative stimulus signals that a response will be reinforced (e.g., a pigeon pecks a key only when a green light is on). Generalization occurs when the organism responds to similar stimuli (pecking when a yellow-green light is on).
- Instinctive drift: The biological tendency of animals trained through operant conditioning to revert to innate, species-specific behavioral patterns (e.g., raccoons rubbing coins together as if washing food instead of dropping them into a bank).