Operant Conditioning

Operant ConditioningOperant Conditioning – A form of learning in

which voluntary responses come to be controlled by their consequences.What does this mean?

Founded by B.F. Skinner

How did Skinner Study Operant Conditioning?Skinner Box – Small enclosure in which an

animal can make a specific response that is systematically recorded while consequences of response are controlledHow does the device work?

Operant Conditioning Principles

Reinforcement – Occurs when the event following a response increases an organisms tendency to make a responseie.) response strengthened because of what followsExamples

Punishment – Occurs when an event following a response weakens an organisms tendency to make responseie.) response weakened because of what followsExamples

Types of Reinforcement/Punishment

1.) Positive Reinforcement2.) Negative Reinforcement3.) Positive Punishment4.) Negative Punishment

How to remember:Reinforcement- behavior increasesPunishment- behavior decreasesPositive- something is addedNegative- Something is removed

1.) Positive ReinforcementA response is strengthened because it is

followed by a rewarding stimulusIn skinner box, rats press lever more if they are

rewarded with foodReal World Examples:

2.) Negative ReinforcementA response is strengthened because it is followed

by the removal of an unpleasant stimulusIn skinner box, rat would press lever more to avoid

a shockReal World Examples:

3.) Positive PunishmentA response is weakened because it is followed

by an unfavorable stimulusIn Skinner box, rats would stop pressing lever if it

was followed by a shockReal World Examples:

4.) Negative Punishment

A response is weakened because it is followed by the removal of a pleasant stimulusEquate this with “Time out”

Children stop acting out because their toys are removed

Other Real World Examples:

How can Operant Procedures be used?

Shaping – The reinforcement of closer and closer approximations of a desired responseFamily guy clip:

http://www.youtube.com/watch?v=prvSM8TlIeI

Other examples:

ExtinctionExtinction – This term refers to the gradual

weakening and disappearance of a response when it is no longer followed by reinforcementIn Skinner box, rats would stop pressing lever if

food was never deliveredReal World Examples:

Schedules of Reinforcement-Pattern of presentation of reinforcers

over time

Continuous Reinforcement – Every Instance of a response is reinforcedEx.) every time rat presses lever, he receives

food

Intermittent Reinforcement- A response is only reinforced some of the time.4 Types:

1. Fixed Ratio2. Variable Ratio3. Fixed Interval4. Variable Interval

4 Types of Intermittent Reinforcement1. Fixed Ratio2. Variable Ratio3. Fixed Interval4. Variable Interval

Terminology BreakdownFixed – Reinforcement occurs after set # (of

responses or hours)Variable- Reinforcement occurs after a varied # (of

responses or hours)Ratio – Based on responses (# of times hit lever, for

example)Interval – Based on time (# of hours passed, for

example)

1.) Fixed RatioA reinforcer is given after a set (or fixed)

number of responsesExamples:

Rat receives food every 10th lever press

2.) Variable RatioA reinforcer is given after varied number of

responsesExamples:

Rat gets food, on average, every 10th lever press

3.) Fixed IntervalA reinforcer is given after a set (or fixed) time

intervalExamples:

Rat given food for lever press every 2 minutes

4.) Variable Interval

A reinforcer is given after a varied amount of time passes

Examples: rat given food, on average, every 2 minutes.

Ratio Schedules = more rapid respondingWhy?

Variable Schedules = greater resistance to extinctionWhy?