Operant Conditioning

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Operant Conditioning
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Operant Conditioning

• Operant 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

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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 controlled
• How does the device work?

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Operant Conditioning Principles

• Reinforcement Occurs when the event following a
  response increases an organisms tendency to make
  a response
• ie.) response strengthened because of what
  follows
• Examples
• Punishment Occurs when an event following a
  response weakens an organisms tendency to make
  response
• ie.) response weakened because of what follows
• Examples

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Types of Reinforcement/Punishment

• 1.) Positive Reinforcement
• 2.) Negative Reinforcement
• 3.) Positive Punishment
• 4.) Negative Punishment
• How to remember
• Reinforcement- behavior increases
• Punishment- behavior decreases
• Positive- something is added
• Negative- Something is removed

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1.) Positive Reinforcement

• A response is strengthened because it is followed
  by a rewarding stimulus
• In skinner box, rats press lever more if they are
  rewarded with food
• Real World Examples

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2.) Negative Reinforcement

• A response is strengthened because it is followed
  by the removal of an unpleasant stimulus
• In skinner box, rat would press lever more to
  avoid a shock
• Real World Examples

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3.) Positive Punishment

• A response is weakened because it is followed by
  an unfavorable stimulus
• In Skinner box, rats would stop pressing lever if
  it was followed by a shock
• Real World Examples

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4.) Negative Punishment

• A response is weakened because it is followed by
  the removal of a pleasant stimulus
• Equate this with Time out
• Children stop acting out because their toys are
  removed
• Other Real World Examples

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How can Operant Procedures be used?

• Shaping The reinforcement of closer and closer
  approximations of a desired response
• Family guy clip
• http//www.youtube.com/watch?vprvSM8TlIeI
• Other examples

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Extinction

• Extinction This term refers to the gradual
  weakening and disappearance of a response when it
  is no longer followed by reinforcement
• In Skinner box, rats would stop pressing lever if
  food was never delivered
• Real World Examples

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Schedules of Reinforcement -Pattern of
presentation of reinforcers over time

• Continuous Reinforcement Every Instance of a
  response is reinforced
• Ex.) every time rat presses lever, he receives
  food
• Intermittent Reinforcement- A response is only
  reinforced some of the time.
• 4 Types
• 1. Fixed Ratio
• 2. Variable Ratio
• 3. Fixed Interval
• 4. Variable Interval

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4 Types of Intermittent Reinforcement

• 1. Fixed Ratio
• 2. Variable Ratio
• 3. Fixed Interval
• 4. Variable Interval
• Terminology Breakdown
• Fixed 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)

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1.) Fixed Ratio

• A reinforcer is given after a set (or fixed)
  number of responses
• Examples
• Rat receives food every 10th lever press

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2.) Variable Ratio

• A reinforcer is given after varied number of
  responses
• Examples
• Rat gets food, on average, every 10th lever press

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3.) Fixed Interval

• A reinforcer is given after a set (or fixed) time
  interval
• Examples
• Rat given food for lever press every 2 minutes

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4.) Variable Interval

• A reinforcer is given after a varied amount of
  time passes
• Examples rat given food, on average, every 2
  minutes.

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• Ratio Schedules more rapid responding
• Why?
• Variable Schedules greater resistance to
  extinction
• Why?