Instrumental Conditioning Foundations
Thorndike’s Puzzle Boxes
One cat’s data (all of the others are similar):
"Of several responses made to the same situation those which are accompanied or closely followed by satisfaction to the animal will, other
things being equal, be more firmly connected with the situation, so that, when it recurs, they will be more likely to recur; those which are
accompanied or closely followed by discomfort to the animal will, other things being equal, have their connections to the situation
weakened, so that, when it recurs, they will be less likely to occur. The greater the satisfaction or discomfort, the greater the strengthening
or weakening of the bond."
The Skinner Box
Some basic terminology
R -- Rfer
Contingency
Positive Rfer
Consequence:
Negative Rfer
Positive (presented)
Negative (removed)
positive reinforcement
negative punishment
(reward)
(omission)
Positive punishment
negative reinforcement
(escape)
Instrumental extinction
R -- 000
Some initial side-effects with operant extinction:
1) Increase in response frequency
2) Increase in response vigor (force)
3) Increase in response variability
A fourth element: the discriminative stimulus
SD (S+)
S (S-)
Shaping in Four Easy Steps
1) identify the target, current behaviours
2) Construct a list of “successive approximations” to the target
3) Starting with the first item on the list, reinforce until frequency is stable
4) Put the behavior on extinction until next “successive approximation” behavior is performed,
return to step 3.
Instinctive drift
-Brelands’ studies
Chaining
-must identify each step of the chain in terms of an A-B-C contingency
-each consequence sets up the antecedent of the next behavior in the chain
Forward, backward, total task
Response-reinforcer relationship
-contiguity versus contingency
-superstitious learning
Partial Reinforcement Schedules
Cumulative Recorder
Partial Reinforcement Schedules
VR
FR
FI
VI