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Operant
Conditioning

Discover how consequences shape behavior through reinforcement and punishment: the foundation of B.F. Skinner's learning theory.

AP Psychology

What Is Operant Conditioning?

Operant conditioning is a type of associative learning in which a behavior becomes more or less likely depending on its consequences. Unlike classical conditioning, where associations form between stimuli, operant conditioning links voluntary behaviors to outcomes.

B.F. Skinner and the Skinner Box

Skinner Box (Operant Chamber) Lever Food Dispenser Rat Press → Food Behavior (press lever) → Consequence (food) Behavior becomes more frequent

Skinner placed animals in an operant chamber to study how consequences influence behavior. When a rat pressed a lever and received food, the lever-pressing behavior increased in frequency.

The Core Principle

Behavior (Voluntary action) Consequence (What follows) Future Behavior Feedback loop: consequence modifies future behavior

The Four Quadrants of Operant Conditioning

Add Stimulus \(+\)
Remove Stimulus \(-\)
 Increase Behavior Decrease Behavior Positive Reinforcement Add pleasant stimulus e.g., Give treat after trick Negative Reinforcement Remove aversive stimulus e.g., Seatbelt stops buzzer Positive Punishment Add aversive stimulus e.g., Speeding ticket Negative Punishment Remove pleasant stimulus e.g., Lose phone privileges

Reinforcement: Strengthening Behavior

Positive Reinforcement
Adding a desirable stimulus after a behavior to increase its frequency. Example: A student studies hard and receives praise from the teacher.
Negative Reinforcement
Removing an aversive stimulus after a behavior to increase its frequency. Example: Taking aspirin removes a headache, so you take aspirin again.

Punishment: Weakening Behavior

Positive Punishment
Adding an aversive stimulus after a behavior to decrease its frequency. Example: A child touches a hot stove and feels pain.
Negative Punishment
Removing a desirable stimulus after a behavior to decrease its frequency. Example: A teenager breaks curfew and loses car privileges.

Operant vs. Classical Conditioning

Operant Conditioning Classical Conditioning
Behavior type Voluntary Involuntary (reflexive)
Association Behavior → Consequence Stimulus → Stimulus
Key researcher B.F. Skinner Ivan Pavlov
Association Timing Consequence follows behavior Stimulus precedes response
Example Dog sits → gets treat Bell → salivation

Schedules of Reinforcement

Fixed-Ratio (FR)
Reinforce after a set number of responses. E.g., buy 10 coffees, get 1 free.
Variable-Ratio (VR)
Reinforce after an unpredictable number of responses. E.g., slot machines.
Fixed-Interval (FI)
Reinforce the first response after a fixed time period. E.g., weekly paycheck.
Variable-Interval (VI)
Reinforce the first response after an unpredictable time. E.g., pop quizzes.

How to Identify the Quadrant

1
Identify the behavior. What voluntary action is the organism performing?
2
Identify the consequence. What happens immediately after the behavior?
3
Does the behavior increase or decrease? Increase = reinforcement. Decrease = punishment.
4
Was something added or removed? Added = positive. Removed = negative.

Example 1: Positive Reinforcement

Behavior Dog sits on command Consequence Owner gives
treat \(+\)
 Result Dog sits more often ↑

Example 2: Negative Reinforcement

Behavior Put on seatbelt Consequence Buzzer stops
\(-\)
 Result More likely to buckle up ↑

Example 3: Negative Punishment

Behavior Teen breaks curfew Consequence Lose phone
privileges \(-\)
 Result Less likely to break curfew ↓

Shaping and Extinction

Shaping
Reinforcing successive approximations toward a desired behavior. Used to teach complex behaviors step-by-step. Example: teaching a pigeon to spin by rewarding each partial turn.
Extinction
When a previously reinforced behavior no longer receives reinforcement, it gradually decreases. Example: ignoring a child's tantrums until they stop.

Common Mistakes

✕ Negative = Bad
"Negative" does not mean bad. It means removing something. Negative reinforcement increases behavior by taking away an aversive stimulus.
✕ Punishment = Effective
Punishment suppresses behavior temporarily but often does not eliminate it. It can also produce fear, aggression, or avoidance without teaching the desired behavior.
✕ Mixing Up Conditioning Types
Students confuse negative reinforcement with punishment. Remember: reinforcement always increases behavior; punishment always decreases it.

Summary of All Four Quadrants

Quadrant Operation Effect on Behavior Example
Positive Reinforcement Add pleasant Increase ↑ Praise after studying
Negative Reinforcement Remove aversive Increase ↑ Aspirin removes headache
Positive Punishment Add aversive Decrease ↓ Spanking after misbehaving
Negative Punishment Remove pleasant Decrease ↓ Lose recess for fighting

Question 1 of 5

A child cleans their room and receives a sticker as a reward. The child then cleans their room more often. This is an example of:

Question 2 of 5

A rat presses a lever and the electric shock in its cage turns off. The rat presses the lever more frequently. Which type of operant conditioning is this?

Question 3 of 5

A slot machine pays out after an unpredictable number of pulls. Which schedule of reinforcement does this represent?

Question 4 of 5

A teacher stops giving gold stars for completed homework, and students gradually stop completing it. This process is called:

Question 5 of 5

Which of the following best illustrates shaping?