PSYC 356 Lecture Notes - Lecture 4: Organism, Reinforcement, Conditioned Taste Aversion
Classical Conditioning (Twitmyerian Conditioning)
Lecture Overview:
● Historical beginnings
● Basics of classical conditioning
● Experimental paradigms
● Elicited Behaviors are simple processes:
○ Involve changes in one’s repertoire
○ Do not involve learning new responses
● Classical Conditioning is more complex:
○ Organism learns relationship between stimuli
○ New behavioral responses are learned
○ Novel associations increase survival
● Edwin B. Twitmyer (1873-1943)
○ Rang a bell just prior to hitting the patellar tendon
○ The bell became sufficient to elicit knee- jerk reflexes
● Ivan P. Pavlov (1849-1936)
○ Dogs increased stomach juices with the sight of food
○ “Psychic juices” sold to the public to support the lab
Modern Classical conditioning paradigms with animals:
● Fear conditioning
● Eyeblink conditioning
● Sign tracking (Autoshaping)
● Taste aversion
We can use animals to study fear conditioning
Subject:
Mr. Rat
US: Shock
CS: Tone (or light)
CR: Behavior
CS CR’s
↑ Blood Pressure
↑ Heart Rate
↑ Stress Hormones
Freezing
● Freezing is a primary species- specific defensive response
● Researchers measure how freezing affects ongoing activity
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Rang a bell just prior to hitting the patellar tendon. The bell became sufficient to elicit knee- jerk reflexes. Dogs increased stomach juices with the sight of food. Psychic juices sold to the public to support the lab. We can use animals to study fear conditioning. Freezing is a primary species- specific defensive response. Researchers measure how freezing affects ongoing activity. Acquisition: rats are trained to press lever for food. Cr- rats freeze ie. lever pressing suppressed. Suppression is specific to cs and once tone is off, lever pressing begins again ie. over trials the tone elicits suppression. Conditioned suppression is quantified with the suppression ratio. B= response prior to the 2 min cs. = 0. 5 : no change in pressing during cs. Trial 1- a= 30, b= 30 30/(30+30) = 0. 5. Trial 9- a= 1, b= 30 1/(1+30) = 0. 03. Useful for the study of neurobiological substrates of learning. No changes between groups in session 1.
