What is Operant Conditioning?

Operant conditioning examines how voluntary behaviour is shaped by consequences. This week focuses on reinforcement, schedules of reinforcement, shaping, and differential reinforcement techniques.

Classical vs Operant Conditioning

Feature	Classical Conditioning	Operant Conditioning
Type of behaviour	Involuntary, reflexive	Voluntary, intentional
Learns what?	Association between two stimuli	Association between behaviour and consequence
Response type	Automatic (UCR/CR)	Goal-directed behaviour
Example	Dog salivates to bell	Rat presses lever for food

The Skinner Box

Used to measure operant conditioning in controlled environments.

Component	Description
Response	Defined behaviour (lever press, peck) required to obtain reward
Reinforcer	Food or liquid released as reward
Cues	Signals indicating whether reinforcement is available
Measurement	Frequency and timing of responses

Links closely to Thorndike’s Law of Effect: behaviours followed by satisfying outcomes are strengthened.

Shaping

Shaping = reinforcing successive approximations of the target behaviour.

Process:

1. Reinforce any behaviour close to the desired behaviour.
2. Gradually require behaviours closer to the target.
3. Withhold reinforcement for non-target actions.

Used to teach new or complex behaviours.

Types of Reinforcers

Definition Table

Category	Definition	Effect on Behaviour
Positive reinforcement	Adding a desirable stimulus	Increases behaviour
Negative reinforcement	Removing an aversive stimulus	Increases behaviour
Positive punishment	Adding an aversive stimulus	Decreases behaviour
Negative punishment	Removing a desirable stimulus	Decreases behaviour

Examples

Type	Example
Positive reinforcement	Giving stickers for good behaviour
Negative reinforcement	Removing a painful rock from shoe → encourages wearing shoes
Positive punishment	Scolding or smacking for misbehaviour
Negative punishment	Taking away screen time after failing an exam

How to Identify Them (Two-Step Rule)

1. Is behaviour increasing or decreasing?
   • Increasing → reinforcement
   • Decreasing → punishment
2. Is something added or removed?
   • Added → positive
   • Removed → negative

Emotional Effects of Each Consequence Type

Type	Emotional Impact	Notes
Positive reinforcement	Satisfaction, motivation	Most effective for long-term change
Negative reinforcement	Relief	Can maintain avoidance behaviours
Positive punishment	Fear, anxiety	Weak for long-term change; ethical concerns
Negative punishment	Disappointment	Effective for reducing specific behaviours

Schedules of Reinforcement

Continuous Reinforcement

• Behaviour reinforced every time.
• Useful for establishing new behaviour.
• Behaviour extinguishes quickly once reinforcement stops.

Partial (Intermittent) Reinforcement

Schedule	Definition	Response Pattern	Resistance to Extinction	Examples
Fixed Ratio (FR)	Reinforcement after fixed number of responses	High rate, pauses after reward (post-reinforcement pause)	Low to moderate	Piecework pay
Variable Ratio (VR)	Reinforcement after unpredictable number of responses	Very high rate, steady	Very high	Gambling, slot machines
Fixed Interval (FI)	Reinforcement available after fixed time	Scalloped pattern; increased responding near time limit	Low	Studying before exams
Variable Interval (VI)	Reinforcement after unpredictable intervals	Steady, moderate rate	High	Fishing

Key terms:

• Post-reinforcement pause (PRP): seen in fixed ratio schedules.
• Ratio strain: break in responding when ratio requirements become too high.
• Ratio run: rapid responding leading up to reinforcement.

Differential Reinforcement Techniques

Used in applied behaviour analysis to increase desired behaviours and reduce unwanted ones.

Type	Definition	Example
DRO (Other Behaviour)	Reinforce any behaviour except the problem behaviour	Reward students for staying silent rather than calling out
DRL (Low Rates)	Reinforce behaviour only when it occurs at low rates	Reinforce washing hands once instead of repeatedly
DRI (Incompatible Behaviour)	Reinforce behaviour incompatible with the undesired behaviour	Reward sitting in seat to prevent running
DRA (Alternative Behaviour)	Reinforce a more appropriate alternative behaviour	Reward saying “please” instead of whining

What Makes Reinforcement Effective?

Factor	Description
Reinforcer magnitude	Larger rewards produce faster learning
Contrast effects	Changing reward value in one context affects behaviour in another
Delay of reinforcement	Longer delays weaken learning; may accidentally reinforce other behaviours (superstitious behaviour)
Speed of reward	Faster reinforcement increases dopamine release
Primary reinforcers	Reinforcers with intrinsic biological value (food, water, warmth)
Secondary reinforcers	Reinforcers that gain value through association with primary reinforcers (money, tokens, praise)

Strength of Secondary Reinforcers Depends On:

• Size/magnitude of primary reinforcer
• Number of pairings
• Timing between secondary and primary reinforcer

Premack Principle

A high-probability behaviour can reinforce a low-probability behaviour.
Example: “You can play outside after you finish homework.”

Chaining

Teaching complex behaviours by breaking them into small steps and reinforcing each link.

Type	Description
Forward chaining	Teach steps in order from first to last
Backward chaining	Teach final step first; work backwards