Lecture 3: Learning (Curtis) Flashcards
mechanisms of behavior
underlying machinery that makes behavior happen –> physical machinery in the CNS
learning
an enduring change in the MECHANISMS OF BEHAVIOR involving specific stimuli and/or responses that results from prior experience with similar stimuli and responses
-> defined in terms of a change in the mechanisms of behavior rather than a change in the behavior itself
the startle response
a defensive response of evolutionary importance
ex: a sudden jump and tensing of the muscles
habituation
a DECREASE IN RESPONSE as a consequence of repeated exposure to a stimulus even though the stimulus remains the same
ex: a mare no longer threatening people when they walk by her baby and nothing bad happens
two important things to remember about habituation:
the initial response (mare being threatening toward people when near her baby) is an INNATE repsonse.
the decrease in response (mare no longer being threatening to people) is LEARNED
what goes on neurologically with habituation?
response fails to occur because changes in the CNS block the relay or sensory neural impulses to the motor neurons
dishabituation
the habituated response is restored by exposure to a strong extraneous stimulus paired with the stimulus to which the animal has habituated
ex: a human actually does threaten the foal, then the mare returns to threatening passerby again
sensitization
an increase in responsiveness produced by repeated stimulation.
more intense stimuli produce greater increases in responsiveness and with more intense stimuli the sensitization effects persist longer
similarities between sensitization and habituation
both reflect how an organism ends up sorting out what stimuli to ignore and what stimuli to respond to
both processes involve learning about just one stimulus
classical conditioning
simple mechanism whereby an organism learns about RELATIONSHIPS BETWEEN STIMULI and alters its behaviors accordingly
unconditioned stimulus (US)
elicits a particular response without the necessity of prior training
unconditioned resposne
response that occurs without prior conditioning
conditioned stimulus
does not elicit a particular response initially, but comes to do so as a result of becoming associated with a US
conditioned response
response that comes to be made to the conditioned stimulus as a result of classical conditioning
the number of pairings needed between a conditioned stimulus and a neutral stimulus depends on:
- intensity of stimulus
2. relevance of neutral stimulus
stimulus discrimination
when only ONE SPECIFIC STIMULUS elicits the response
stimulus generalization
response elicited by a diverse but related group of stimuli
taste aversion learning - what is it and what are its 2 unique properties?
a robust form of classical conditioning
ex: an animal eats something –> gets sick. source of the CS and US is the same.
- strong taste aversions can be learned with just one pairing
- learning occurs even if animal does not get sick until several hours after exposure
extinction
if animal is repeatedly exposed to a CS without further pairing with the US, then the animal response will eventually cease
ex: if you stop pairing the whistle with the fish, the whistle wont have the same meaning anymore
what is the difference between extinction and habituation?
habituation is loss of an INNATE response
extinction is loss of a LEARNED response
in both situations, the stimulus intensity remains the same but the response decreases
operant conditioning (instrumental conditioning)
behavior that is affected by the immediate consequences. the behavior occurs because it was previously instrumental in producing certain responses. ie goal directed behavior
ex: a dog has learned that the action of sitting when a person says “sit” results in food.