Extinction in Classical Conditioning

1
Extinction in Classical Conditioning

• The process of unlearning a CR
• How can you get a CR to stop occurring?
• What would you do to get Pavlovs dog to stop
  salivating to the sound of the tone?
• The key is to break the association between the
  CS and the US

2
Types of Extinction Procedures

• Standard Extinction
• Present the CS without the US
• For example, sound the tone but dont give the
  dog any food
• Random Extinction
• Present the CS and the US at random times
• Although the CS and US may occur together
  sometimes, no contingency exists between them

3
Characteristics of Extinction

• Responses undergoing extinction display a
  negatively accelerated curve

4
Characteristics of Extinction

• A CR undergoing extinction will display
  spontaneous recovery
• Spontaneous recovery occurs when a CR returns
  because of the passage of time
• It is a natural characteristic of behavior

5
Characteristics of Extinction

• Disinhibition
• The presentation of a novel stimulus will cause a
  return of the extinguished response

6
What to Remember about Extinction

• The CR will go away, but not all at once
• Extinction is not the same as forgetting
• The passage of time will cause the response to
  return
• Its strength will dissipate across successive
  time intervals
• A novel situation may cause its return

7
Other Characteristics of Classical Conditioning

• Stimulus generalization
• The process in which a similar response is given
  to a novel, but similar, stimulus
• Déjà vu is an example of stimulus generalization

8
Other Characteristics of Classical Conditioning

• Stimulus Discrimination
• Learning to respond differently to different
  stimuli
• Peak shift may occur
• The strongest response may not be to the original
  CS

9
Other Characteristics of Classical Conditioning

• Overshadowing
• When two or more CSs are paired with a single US,
  the more salient of the two CSs will produce the
  strongest CR
• For example, flashing lights and a siren are both
  predictors of an emergency vehicle, but most of
  us have a stronger response to one than the other

10
Other Characteristics of Classical Conditioning

• Blocking
• Once a CS has become a perfect predictor of an
  US, an organism will not learn to respond when a
  new CS is paired with that US
• In other words, new learning is blocked
• For example, although the walk signal is a
  perfect predictor of the light turning red, we
  have no response. Rather, we respond to the
  yellow light

11
Responding to the US

• Classical conditioning is about how organisms
  come to respond to previously neutral stimuli
• However, it needs to be noted that an organisms
  response to the US will not remain constant
• Two changes will occur

12
Sensitization

• Sensitization is an increased responsiveness to
  the initial presentations of the US
• ExampleWhen you hear a faucet dripping in the
  middle of the night, it often seems to get louder
• Thats sensitization
• It is relatively short lived

13
Habituation

• Habituation is a decreased responsiveness upon
  repeated or prolonged presentations of the US
• Example Although the sound of the dripping
  faucet initially seems louder, ultimately you
  fall asleep
• Thats habituation

14
Characteristics of Habituation

• A habituated response displays a negatively
  accelerated curve
• Spontaneous recovery will occur
• That is, a habituated response will return with
  the passage of time
• Dishabituation will occur
• The presentation of a novel stimulus will cause
  the return of the response

15
Characteristics of Habituation

• Habituation occurs more quickly when the US is
  presented more, rather than less, frequently
• Habituation occurs more quickly to weak, than to
  strong, stimuli
• Habituation occurs more quickly when the US is
  presented at regular, rather than variable,
  intervals

16
Why be concerned with Habituation?

• Because classical conditioning occurs best when
  the US is intense, youll want to make sure that
  the person hasnt habituated to the US
• You may want to alter a persons response to the
  US
• Habituation suggests that you need to present the
  US often

17
Extinction vs. Habituation

• Differences
• Extinction occurs to the CS
• Habituation occurs to the US
• Similarities
• Both share the same characteristics (e.g.,
  spontaneous recovery, etc)