Operant Conditioning

Complex Learning

Why do we learn new behaviors? Classical conditioning only deals with reflex

responses that we already possess. Most of our behaviors are voluntary.

Volitional. Stimulated by something in our environment.

Operant Conditioning

Defined as - the form of learning concerned with changes in emitted responses as a function of their consequences.

Origins of Operant Conditioning

Edward Thorndike Instrumental

Conditioning “Law of Effect”

Satisfying outcome Unsatisfactory outcome

Outcomes of Thorndike’s Work

As it declined learning was taking place.

Learning

How Long - the length of time it took the cat to escape from the puzzle box. This change in performance represented a change in behavior from experience.

Question

In Thorndike’s terms, what sort of things give you satisfaction? What things produce dissatisfaction? Why?

Edward Thorndike

His research provided a foundation for the study of “non-reflexive” learning.

He drew a connection between action and its outcomes.

B. F. Skinner

Skinner coined the term “operant”.

Disagreed with the “soft” concepts of Thorndike’s “satisfying” and “unsatisfactory” outcome(s)

B. F. Skinner

Operant Conditioning replaced Thorndike’s term “instrumental learning”

Emitted behavior is now called “operant responses”

Classical conditioning is now called ‘respondent conditioning.

The Skinner Box or “auto-environmental chamber”

Zack Florin '99 using a Skinner  box to shape a rat's behavior 

Skinner Box in Action

Reinforcment

Primary reinforcers - food, water, shelter. Those innate biological needs.

Secondary reinforcers (Conditioned reinforcers) - something that will provide a primary reinforcer. (money, poker chips etc.)

Primary vs. Secondary

Which of the following are secondary reinforcers: quarters spilling from a slot machine, a winner’s blue ribbon, a piece of candy, an A on an exam, frequent-flyer miles.

Reinforcement

Negative Reinforcer - an aversive stimulus which serves to decrease the probability of the response in the future.

Positive Reinforcer - a stimulus which when applied increases the probability of the response in the future.

Contingencies of Reinforcement

According to Skinner the relationship between a response and a reinforcer is a contingency.

One type of contingency is “reinforcement”

Desired change in behavior

Type of reinforcer Increases response Decrease response

Positive reinforcer POSITIVE REINFORCEMENT

OMISSION(withholding positive reinforcer)

Negative reinforcer NEGATIVE REINFORCEMENT (escape, avoidance)

PUNISHMENT

Shaping

Some learning does not occur in a single event.

A series of successive steps leads to a learned behavior.

Playing the piano, swimming etc.

Applying the Principles

When asked choose the best alternative and explain why. You want your 2-year-old to ask for water with a

word instead of a grunt. Should you give him water when he says “wa-wa” or wait until his pronunciation improves.

Applying the Principles

When asked choose the best alternative and explain why. Your roommate keeps interrupting your studying

even though you have asked her/him to stop. Should you ignore her/him completely or occasionally respond for the sake of good manners?.

Applying the Principles

When asked choose the best alternative and explain why. Your father, who rarely writes to you, has finally

sent a letter. Should you reply quickly or wait a while so he will know how it feels to be ignored?.

Extinction

What happens when the reinforcement stops.

Extinction - in operant conditioning, a drop I responding when reinforcement is discontinued.

Schedules of Reinforcement

Continuous reinforcement - every response is followed by a reinforcer. (FR1 schedule)

Partial reinforcement - a contingency of reinforcement in which every response does not get a reinforcer.

Fixed Interval Schedule

Referred to as FI x - reinforcement contingency defined by the amount of time that must pass since the previous reinforcer.

Based on time. Example: pay checks

Fixed Ratio Schedule

Referred to as FR x - reinforcement contingency defined by the number of responses the organism must make in order to get a reinforcer.

Example: piece work.

Variable Interval Schedule

Referred to as VI x - a reinforcement contingency defined by the average time interval which must elapse since the last reinforcer.

Example: Quality Control

Variable Ratio Schedule

Referred to as VR x - a reinforcement contingency defined in terms of the average number of responses required to receive a reinforcer.

Example: Slot Machine

Non-Contingent Reinforcement

Random “reinforcement”

Development of what Skinner called ‘superstition’ in the pigeon.

Applying Conditioning

We must always keep in mind that all this is done to match the goals of psychology.

Behavior Modification. Mary Cover Jones - the mother of behavior

therapy Controls AversivePositive

Punishment

Most used and most misunderstood

Occurs after the ‘offense’ has taken place.

Requires “contiguity” Encourages avoidance

behaviors.

Negative Reinforcement

Autonomic Conditioning

Neal Miller and Leo DiCara

‘proprioceptive feedback

Biological Constraints

Some unanswered questions: Equipotentiality

premise Ethology Species-specific

behavior Critical period Preparedness

• The premise that principles of conditioning will apply to any response and any species.

The study of the behavior of animals in their natural environment.

Behaviors which are characteristic of all members of a particular species. (instincts)

A period during development where there are optimal periods for learning.

A concept developed by Martin Seligman to describe how physiological structure influences the occurrence of behavior

Biological Constraints

Prepared Unprepared Contraprepared

Degree of biological preparedness

Species-specific behavior

Bait Shyness Classical and operant conditioning

Unlearnable Associations