Classical conditioning

1
Classical conditioning

• Forging connections between formerly unrelated
  events

2
background

• It all started with Ivan Pavlov and his study of
  the digestive system
• Research based on work with animals
• Wildly successful 1905 Nobel Prize
• Studied the automatic connection between food
  (meat) in the mouth and the flow of digestive
  juices
• UCS (meat in mouth) gt UCR (saliva)

3
The big idea

• Start with an unconditioned reflex an automatic
  connection between a stimulus and a response
  (meatgtsaliva)
• You can develop new automatic responses by
  transferring responses from an UCS to an
  originally neutral stimulus by repetitively
  pairing them together

4
Lets say that a different way

• An air puff in the eye (UCS) will always make us
  blink (UCR)
• Flashing a red card wont
• But if we repetitively flash the red card,
  shortly followed by the air puff, eventually,
• Just flashing the red card will make us blink !

5
New terms

• The initially unremarkable red card is a neutral
  stimulus (NS)
• The air puff is an UCS
• The blink after just the puff is a UCR
• The red card, once it causes a blink all by
  itself, is a conditioned stimulus (CS)
• The blink that follows just the red card is a
  conditioned response (CR)

6
examples

• That particular corner at you high school
• The torturers black shoes
• The song from that certain summer that reminds
  you of ..
• Pavlovs assistants carrying the meat tray
• The tone before the shock
• The whistling of a V1 shrieked
• Sexual fetishes

7
definitions

• Classical conditioning (CC) process by which an
  organism learns a new association between two
  paired stimuli one of which was initially
  neutral the other producing an unconditional
  reflex
• Unconditioned stimuli (UCS) an event that
  constantly and automatically elicits an
  unconditioned response (UCR)

8
More definitions

• Unconditioned response (UCR) an action that an
  UCS elicits
• Conditioned response (CR) action that
  Conditioned Stimulus elicits it does not have to
  be identical to the UCR

9
perspectives

• CC works across species, from the lowly maggot to
  the most sophisticated human being
• In habituation the UCS proved to be meaningless
  and lost its power over behavior
• In CC the initially meaningless CS becomes
  crucial and works a heavy influence on behavior

10
More perspectives

• CC prepares us for significant events by
  identifying events that commonly predict them
• Gives us advance warning of upcoming threats and
  opportunities
• The more unfamiliar the CS or the more powerful
  the UCS the faster the CR takes

11
Other aspects

• The process that establishes or strengthens a CR
  is called acquisition
• A CR can even be a thought

12
Unraveling the connection

• Extinction the decrease or extinguishment of
  the conditioned response
• In CC, extinction takes place when we repeatedly
  present the CS without the UCS following it

13
The return of the csgtCR connection

• Extinction doesnt erase the CSgtCR connection, it
  inhibits it
• Spontaneous recovery the temporary return of
  the extinguished response after a delay

14
All together now

• First we build the CSgtCR connection through
  acquisition,
• Then we unravel it through extinction,
• If we then stop presenting the CS for a while,
  once we resume its use,
• The CR will return, but not for long, unless it
  is again paired with the UCS

15
Extending the connection

• The CR can occur even without presentation of the
  exact CS which formed it, if the new CS is
  similar enough
• Stimulus generalization the extension or
  broadening of a CR from the original CS to
  another, similar stimulus
• The more similar the entire setting is, the more
  likely the new connection will form

16
Narrowing connections

• If differing stimuli, although quite similar to
  the CS, are never, or rarely, followed by the
  UCS, then the CR will not emerge
• Stimulus generalization differing responses to
  differing stimuli that have been followed by
  differing events

17
What factor is key to cc?

• What causes the connection to form?
• Pavlov thought that the most important element in
  acquisition was how closely the UCS followed the
  CS.
• We call it temporal contiguity or nearness is
  good
• After all, the longer the break between the CS
  and the UCS, the weaker the connection.

18
Is it just timing?

• The concept of blocking.
• If a CS/CR link has been established, pairing a
  new CS with the old CS will not work.
• This is true even if the timing is perfect for
  the new CS.
• So, nearness in time is not enough.

19
The power of prediction

• Its reliability that counts, the CS ability to
  accurately and consistently predict the UCS.
• The UCS must be more likely to occur after the CS.

20
The big picture

• CC involves visceral reactions involving the
  sympathetic nervous system you feel it in your
  gut.
• It prepares us for important challenges and
  threats.
• But it does not tell us what to do.
• For how we learn voluntary, planned behaviors we
  turn to operant conditioning.