Lecture 3 - Schedules of Reinforcement + Extinction

Schedules of Reinforcement

Specifies which responses will be followed by the reinforcer

Continuous reinforcement -

Each response is followed by the reinforcer

Intermittent reinforcement -

Not every response is followed by a reinforcer

Fixed Ratio Schedules

Reinforcer is delivered after X number of responses - the number does not change (the number is fixed)

Produces high rate of responding, but there’s often a post reinforcement pause

Fixed Ratio Schedules examples

• Examples: piece rate pay

• classroom uses

every 10 pages you read you get candy

what does FR5 mean

• FR5 schedule means reinforcer is given after every 5th response

Fixed Ratio Schedules: ferster and skinner

descrease in responses after reinforcer

post reinforment pause

Variable Ratio Schedules

Reinforcer after X number of responses on the average

Produces high rate / no post-reinforcement pause (response rate doenst drop)

Variable Ratio Schedules example

• Examples: work and classroom uses

• slot machine

what does VR10 mean

• Ex. VR 10

trial 1: 7 responses → reinforcer

trial 2: 15 responses → reinforcer

trial 3: 3 responses → reinforcer

trial 4: 15 responses → reinforcer

7 + 15 + 3 + 15 = 40 responses

40 responses/4 reinforcers = 10 responses per reinforcer → VR 10

Fixed Interval Schedules

• Reinforcer for the first response after X amount of time - time interval does not change

• Produces low rate of responding that increases at the end of the interval • Rarely used in training programs

Fixed Interval Schedules examples

• mail delivery every 24h

• hourly supervisor checks on a worker

Variable Interval Schedules

• Reinforcer for the first response after X amount of time on the average

• Produces low but steady rate of behavior • Rarely used in training programs

Variable Interval Schedules example

• unpredictable supervisor checks

• checking for phone or e-mail messages

Concurrent Schedules of Reinforcement

Schedules of reinforcement that exist at the same time for two or more different behaviors

• Concurrent operants: different behaviors to choose from

• Concurrent schedules of reinforcement: each behavior has its own schedule

Matching law:

we often choose the behavior that gives us greater reinforcement

Factors influencing choice of concurrent operants

- schedule of reinforcement

- magnitude of reinforcement

- immediacy of reinforcement

- response effort

Combined schedules

= when we put 2 or more reinforcement schedules together

• Ex: FR10+ FI 5min

Concurrent schedules

= each behaviour has it’s own schedule and available at the same (person has to choose)

• Ex: You can study or play video games → both options are available simultaneously

Multiple schedules of Reinforcement

happening ONE AFTER ANOTHER

• reinforcement schedule changes over time, and different discriminative stimuli (SD) signal which schedule is currently active

• Ex: Teacher shows green card for ”participation time” on FR-1, and red card for “quiet, attentive time” VR-5

Extinction:

• Is a basic principle of behavior

• Is supported by years of basic and applied research

• Is a component of many behavior modification procedures

Defining Operant Extinction

1. A previously reinforced behavior

2. Is no longer followed by the reinforcing consequence

3. The behavior is weakened (decreases and stops occurring in the future)

Operant Extinction present vs future

• Present: The behavior is no longer reinforced

• Future : The behavior stops occurring

Push the button in a broken garage door opener – garage door does not open. **In the future……

dont push broken button

Drinking from an empty water bottle – do not get any water** In the future……

not gunna be drinking from that water bottle in the future

Telling unfunny jokes – get no laughs** In the future……

less likely to tell jokes

Trying to use a flashlight with dead batteries – get no light** In the future……

less likely to use those batteries

Calling someone who never answers her phone – do not get any response** In the future……

not call them

Parent stops reacting to child misbehavior – child gets no attention** In the future……

child stops misbehvaing

Look at your wrist when you no longer wear your watch – get no time** In the future……

stop looking at your wrist

Extinction Burst

When the reinforcer no longer follows a particular behavior, three things may happen initially:

1. Increase in frequency, duration, or intensity of the unreinforced behavior

2. Occurrence of novel behaviors

3. Occurrence of emotional and/or aggressive behaviors

Extinction Burst example

when rae does not get her coffee from the vending machine, she pushes the buttons repeatedly and shakes the machine

Spontaneous Recovery

• The behavior occurs again sometime later after it was eliminated with extinction

• Behavior occurs in situations where it was reinforced in the past

Evidence of spontaneous recovery suggests that extinction learning is

a new and separate process from acquisition/learning

Procedural Variations of Extinction

Extinction of positively reinforced behavior

Extinction of negatively reinforced behavior

In both cases behavior is weakened

Extinction of positively reinforced behavior

The positive reinforcer is no longer delivered following the behavior

Extinction of negatively reinforced behavior

The aversive stimulus is no longer removed following the behavior

Factors Influencing Extinction

• The schedule of reinforcement prior to extinction

• The occurrence of reinforcement following the initiation of extinction

• Reinforcement of functionally-equivalent behaviors (shared reinforcer)

Extinction learning in humans

• Exposure therapy (classical Pavlovian extinction)

• Substance-use in specific settings