Instrumental Learning A general class of behaviors inferring that learning has taken place.

Instrumental Learning

• A general class of behaviors inferring that learning has taken place

Two general classes of behaviors

• Free operants

• Fixed trials

The consequences of behavior

• The delivery of a reinforcement

1. Thorndike and the law of effect

• That behavior that immediately preceded the appearance of a satisfying state of affairs (internal to the animal) is a reinforcer

2. Skinner and Operant Behavior

V. Major phenomena of instrumental learning

• Called operant because the animal operates on the environment to acquire a reinforcer

Conditioned reinforcement

• The animal only gets rewarded when an explicit behavior is emitted.

• Acquiring money!!

Note the terms

• One rewards the animal.

• One reinforces a response.

What is a reinforced?

• The explicit narrow behavior that occurs immediately preceding the delivery of the reinforcement.

Reinforcement & Punishment

• Concept – Positive Reinforcement

Description

• Increasing the frequency of a behavior by following it with the presentation of a positive reinforcer – a pleasant, positive stimulus or experience

Example

• Saying “Good job” after someone works hard to perform a task.

Types of reinforces

• Appetitive – usually food

• Negative --- shock, air puff; those stimuli that deliver pain or discomfort.

Positive Reinforcement

Concept:

• Negative reinforcer

Negative Reinforcement

Note the following

• The removal of a negative stimulus is positively reinforcing – the animal will tend to do that behavior that removes itself from the cues associated with the aversive state of affairs.

The Skinner Box

• Any box or device in which a reinforcer can be automatically delivered contingent on the behavior of the animal.

Shaping

• The initial learning – teaching the animal to hit a bar or push a key.

Accumulative record

• A “strip chart’s” ink record of the animals behavior.

Schedules of reinforcement

• Reinforcement based on responses

• Reinforcement based on the passage of time

Fixed Ratio Behavior (FR)

• Reinforcement based on the number of response accomplished. For humans, piece work – payment for the number of things accomplished

Variable Ratio (VR)

• Payment (reinforcement) for the average number of responses accomplished

Fixed Interval (FI)

• Reinforcement for the first response after a fixed period of time has occurred.

• Work by the hour, irrespective of the amount of work accomplished

Variable Interval (VI)

• Reinforcement based on the first response after an average amount of time has passed.

Interval schedules

Combinations of schedules of reinforcement

• Unlimited combinations of schedules

Partial Reinforcement

• Variable ratio and variable interval schedules are harder to extinguish than continues reinforcement

Negative Control of Behavior

• Behavior emitted that removes an aversive state of affairs.

Negative reinforcer

Description: Increasing the frequency of a behavior by following it with the removal of an unpleasant stimulus or experience

Concept

• Avoidance conditioning

Avoidance conditioning

• Description: Learning to make a response that avoids an unpleasant stimulus.

Example

• You slow your car to the speed limit when you spot a police car, thus avoiding being stopped and reducing the fear of a fine; very resistant to extinction

1. Escape and Avoidance

The control of Intrinsic behavior

• Avoidance tasks the removal of one-self from an environment which has previously been associated with a negative reinforcement.

Sidman Avoidance

• Shock-Shock interval (shock every 5 sec)

S. A. (cont.)

• Response shock interval (time delay of shock/bar push)

S. A. (cont.)

• Very, very hard to extinguish.

• VAN - chimp

VIII. Punishment – different types

•

Punishment 2 (Penalty)

Example

• You learn to use the mute button on the TV remote control to remove the sound of an obnoxious commercial

Concept

• Escape Conditioning

Escape Conditioning

• Description: Learning to make a response that removes an unpleasant stimulus

Example

• A little boy learns the crying will cut short the time that he must stay in his room

Concept

• Punishment

Punishment

• Description: Decreasing the frequency of a behavior by either presenting an unpleasant stimulus (punishment 1) or removing a pleasant one (punishment 2 (penalty).

Example

• You swat the dog after it steals food from the table, or you take a favorite toy away from a child who misbehaves. A number of cautions should be kept in mind when using punishment (see below for an example).

Learned helplessness

• Continued punishment until the animal refuses to respond even when there is no aversive state of affairs.

Combined Operant and C. C.