PSYC 356 Lecture Notes - Lecture 8: Autism Spectrum, Belongingness, Classical Conditioning
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PSYC 356 Chapter 5: Instrumental Conditioning: Foundations
Foundations of Instrumental Conditioning
●Instrumental conditioning: Learning associations between stimuli, behavior and their effect on
environment
●Leads to goal-directed behavior in everyday life
●Examples?
○Lose inhibition
○Putting on sunscreen to prevent getting burned
○Exercise to lose weight/ gain muscle
○**whether you're doing something or not; whether it is a positive outcome or not
●Classical Conditioning
○Learning associations between stimuli
○ie. Pavlov’s dogs learned bell meant food was coming
●Instrumental Conditioning
○Learning associations between response and outcome
○ie. lose inhibition, get markered
○There is contingency
E.L. Thorndike (1874-1949):
●Initially interested in intelligence
●Used puzzle boxes:
○Food restricted cats
○Goal was escape and food
○Measured latency to escape
●Cats learned association between stimulus and response:
○Association affected by outcome
○Rope in box (S) + pulling rope (R) →escape (O)
■Change motivation of organism so it wants to escape
■Provide opportunity to get an outcome
Law of Effect:
●Response to a stimulus followed by a satisfying
event strengthened
S-R relationship
○ie. Pull Rope → food and escape → less time to escape
●Response to a stimulus followed by an annoying
(aversive
) event → weakened
S-R relationship
○ie. pull rope in the box → shock → longer time to escape (greater latency)
○You can change behavior in a positive direction (1st) ; you can also inhibit behavior (here)
●Bidirectional effect of a response leading to an outcome modifying a later response of the effect
Modern Approaches:
1. Discrete- Trial Approach
a. Response performed once (only once)
b. Behavior of subject terminates trial
i. Once they perform a behavior, that’s it
ii. Only way is to start the experiment again (ie. moving an organism to the start,
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c. Timing of trial determined by the experimenter
d. Examples?
i. An exam
ii. Maze
1. Baby mice trying to find mother
a. Mother on one side, different rat on other side
2. Once they make their choice, it’s over
a. Only way to do it again is to start the entire experiment (ie. putting
baby rat back at the beginning of the maze)
●Two maze types
○Straight alley
○T- maze
●Behaviors measured:
○Running speed
○Latency to move from start box
○Choice behavior
■ Only applicable to T- maze
2. Free- Operant Approach
a. Subject is “free” to respond at any time
b. May be repeated many times
c. Timing of responses determined by subject
d. Examples?
i.
ii.
iii.
Free- Operant Approaches: Skinner Box
●Skinner Box measures operant response rate:
○ie. # of lever presses for food
●Operant response: Behavior that “operates” on the environment
●Differences between discrete- trial and free- operant approaches?
○
How to produce a target response 101
●Step 1: Magazine Training: Classical Conditioning
○Sound of the magazine (food dispenser is a CS+) followed by food (US) orients organism
○AKA Sign Tracking
○Examples?
■
■
■
●Step 2: Shaping: Instrumental Conditioning
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○Rewarding successive approximations to target behavior by:
1. Reinforcing closer actions to the correct response
2. Not reinforcing earlier responses
○Correct steps are preserved
■ex. The rat still rears up to push the bar
Shaping:
●Combining familiar responses into new behaviors:
○Must be a variable response
○Slowly
step up criteria
○Can bring about SUPER or miniature responses
●Deich, Allan & Zeigler (1988):
○Training beak opening in pigeons
●A response can produce 1 of 2 Outcomes:
○Appetitive stimulus
■Pleasant outcome (getting paid, food, sunshine)
○Aversive stimulus
■Negative outcome (Yelling, shock, cold)
●Contingency: something likely to occur as a result of something else
○Positive contingency: response turns on/ causes an outcome
■A rat can press the lever to get food
○Negative contingency: response turns off/ inhibits an outcome
■A rat can turn off a loud noise by pressing the lever
■The outcome it pleasant
●You do something, something gets taken away you want taken away
Appetitive Stimulus
Aversive Stimulus
Positive Contingency
(Response causes Outcome
)
Positive Reinforcement
Punishment
(Positive Punishment
)
Negative Contingency
(Response inhibits Outcome
)
Omission Training
(Negative Punishment
)
Negative Reinforcement
(Escape of Avoidance
)
Positive Reinforcement:
●Positive contingency between response and appetitive stimulus
○(response turns on a good thing)
Document Summary
Instrumental conditioning : learning associations between stimuli, behavior and their effect on. Leads to goal-directed behavior in everyday life. Putting on sunscreen to prevent getting burned. **whether you"re doing something or not; whether it is a positive outcome or not. Ie. pavlov"s dogs learned bell meant food was coming. Cats learned association between stimulus and response: Rope in box (s) + pulling rope (r) (cid:516)escape (o) Change motivation of organism so it wants to escape. Response to a stimulus followed by a satisfying event strengthened s-r relationship. Response to a stimulus followed by an annoying ( aversive ) event (cid:516) weakened s-r relationship. Ie. pull rope (cid:516) food and escape (cid:516) less time to escape. Ie. pull rope in the box (cid:516) shock (cid:516) longer time to escape (greater latency) You can change behavior in a positive direction (1st) ; you can also inhibit behavior (here)
