Lecture 4: Pavlov Flashcards
Pavlov, general
The organism is either equipped at birth or develops through maturation certain natural connections between some stimuli and some responses.
Such stimuli are naturally followed by responses. Natural stimuli are US and natural responses are UR (such as knee-jerk reflex)
Pavlov “conditioning” = “learning”
In Pavlovian psychology there is no such thing as neutral stimulus because there is an UR to a novel stimulus, and US for orienting / investigating
• E.g. cats orient to any novel stimulus
The orienting reflex habituates or extinguishes quickly
• Orienting reflex interferes with conditioning—if you’ve already made a response, it’s difficult to make a new response
In most cases CR and UR are topographically the same
• In many species fear in the parent is an US for the offspring
The opposite of exposure which is avoidance not only does not produce extinction but it also strengthens the effect
Pavlov’s standing does not really rest on his discovery of conditioned reflex
It lies on his exploration of reflex and coming up with a description of it
o He came up with a language that we use in learning
• e.g. reinforcement (Classical not Operant)
- Pavlov a bigwig in Communist party, very unlikely people would disagree
- After the fall of Communism, dangerous to be Pavlovian, turned to client-centered therapy and psychoanalysis
Reinforcement
Following the CS with the US at appropriate time interval
Reinforcement meant strengthening , not reward
Although the topography of the response is similar it is not the same
e.g. The chemical makeup of saliva is different in CR vs UR
Experimental Extinction
When reinforcement is discontinued and the CS is presented alone, the CR gradually diminishes and disappears
In Pavlovian conditioning nothing ever goes back to normal
*This is a dual system of excitation and inhibition
• The CS either produces excitation or inhibition, one or the other
Spontaneous Recovery
The reappearance of a CR to the CS after an elapsed time without further repetition of any kind
The extinction that occurs to the first 3 trials is very different than trials 30 and 40
Spontaneous recovery, when it occurs, is always on the first trial and you can usually find something that accounts for it—something changed [time, context]
Contiguity
The basic unit of learning for Pavlov was the formation of an association between a stimulus and a response because of their simultaneous action
Because Pavlov substituted one stimulus for another it can be thought of a stimulus substitution theory, therefore it is S-S rather than S-R
Pavlov did not think of food as a reward because it came before the salivation normally. Rather, he thought of food as evoking the response and spoke of it as a reinforcing stimulus
Strengthening because of connection
Generalization
Once the response was conditioned it is not necessary to present the precise CS to obtain the CR—similar stimulus brings out it out
- Without generalization we would have to re-learn all the time
- It can also be harmful, a fear can be generalized
- You can get generaliazation of inhibition as well
Generalization Curve
Used a metronome
CS=60bpm, produces salivation
50bpm or 70bpm, not as much salivation, then less at 40bpm & 80bpm etc
[d.v. amount of salivation]
Peak Shift: if you now make 80bpm a CS-, there is shift in curve, where 50bpm evokes more salivation than original US of 60bpm
Rationale,: 50bpm farther away from 80bpm CS- than 60
Discrimination
Opposite of generalization
Pavlov also was the first to talk about it, which he called “differentiation training”
Temporal Relationships
Overlapping and Non-Overlapping
Overlapping: simultaneous and delayed
Non-Overlapping:
- Short Trace
- Long Trace
- Backward Conditioning
- Forward Conditioning
- Temporal Conditioning
Overlapping: Simultaneous CS-CR
CS-US overlap
CS for 5 seconds alone, CR is response before US
Overlapping: Delayed CS-CR
5seconds –5 minutes, or longer
CR will occur in a way that is proportional to the delay
Organsims salivates before the meat is presented, but after an interval has elapsed from when the bell started–**usually 2/3 of the way into the dalay
Much more difficult for the organism to learn
Requires the teaching of simultaneous pairings first
o E.g. fear responses
Non-Overlapping: Short Trace
Gap of 5 seconds between CS and US
Animal salivates at the end of the bell [when the bell goes off]
Non-Overlapping: Long trace
Gap between CS and US is longer, minute or more
CR presents after interval proportional to size of gap, about 2/3rd
Formed with greater difficulty than with Delayed CRs
Non-Overlapping: Backward Conditioning
US is presented before the CS
Works only in very unusual circumstances
CS becomes inhibitory CS-
Non-Overlapping: Temporal Conditioning
Passage of time functions as the CS
US is presented at regular intervals of time, if US is omitted, CR will occur at the approximate interval
