Schedules of Reinforcement Continuous Reinforcement (CRF ...

Schedules of Reinforcement
• Continuous Reinforcement (CRF) - Every response is followed by reinforcement
• Partial Reinforcement - Not every response is followed by reinforcement
Partial-Reinforcement Schedules
• Fixed Ratio (FR) - Reinforcement provided after a fixed number of responses
Patterns of Responding on FR Schedules
• Post-reinforcement Pause - pause in responding immediately after reinforcement
• May be an analogue of procrastination
• Duration of pause related to size of FR schedule
• Ratio Run - high rate of responding following pause
• Ratio Strain - decrease in responding when ratio requirement is too high
Variable-Ratio Schedule
• Variable Ratio - a variable number of responses are required to obtain reinforcement
• Responding is relatively consistent and high
• Post-reinforcement pause tends to be shorter
Practice Quiz
1. On a _____ schedule of reinforcement each response is reinforced, whereas on
a ______ schedule of reinforcement, only some responses are reinforced.
2. Every time you flick the light switch, the lights come on. This is an example of
______.
3. A schedule on which 15 responses are required for each reinforcer is
abbreviated ______.
4. An FR 1 schedule of reinforcement can also be called a ______ schedule.
5. An FR 200 schedule will result in a (longer/shorter) ______ pause than an FR 50
schedule.
6. About one in ten people approached by a panhandler actually gives him money.
His behavior of panhandling is on a ______ schedule of reinforcement.
7. Graduate students often have to complete an enormous amount of work in the
initial year of their program. For some students, the workload involved is far
beyond anything they have previously encountered. As a result, their study
behavior may become increasingly disorganized throughout the year, a process
known as ______ _______.
8. A variable ratio schedule typically produces a (high/low) _____ rate of behavior
(with/without) ______ a post-reinforcement pause.
Interval Schedules
• Reinforced for first response following a certain period of time
• Fixed Interval (FI) - reinforcement provided for the first response following a fixed
period of time
Fixed-Interval Schedule
• Characteristics of Responding:

• FI scallop - long pause in responding following reinforcement, followed by
accelerating rate
• Greatest responding just prior to end of interval
• Animal learns temporal interval
• Might be similar to inhibition of delay
Variable-Interval Schedule
• Variable Interval (VI) - first response following a variable interval of time is reinforced
• Tends to produce a low to moderate, steady rate of responding
Comparison of Response Rates
Practice Quiz
1. In general, variable interval schedules produce a (low to moderate/high) ______
rate of response. This rate tends to be (steady/fluctuating) ______.
2. Responding on an FI schedule is often characterized by a ______ pattern of
responding.
3. On a pure FI schedule, any response that occurs (during/following) _____ the
interval is irrelevant.
4. On which type of schedule does the rate of responding have the greatest effect
on how often the animal is reinforced?
Other Schedules of Reinforcement
• Differential Reinforcement of High Rates (DRH) - high response rates are reinforced
• Differential Reinforcement of Low Rates (DRL) - low response rates are reinforced
• Differential Reinforcement of Other Behavior (DRO) - reinforced for performing any
behavior other than the specified behavior

Extinction
• Side effects
• Extinction burst – temporary increase in the frequency and intensity of responding
• Increase in Variability
• Emotional Behavior
• Aggression
• Resurgence – reappearance during extinction of other behaviors that had once
been effective in obtaining reinforcement
• Depression
What’s learned during extinction?
• Why does the animal stop responding?
•
S D : RS R
• S: RO (stimulus: response outcome)
• Which does the animal learn?
• Weakening of the R-O association?
• Inhibitory S-O association?
• Inhibitory R-O association?
• Inhibitory S-R association?
Rescorla (1993)
Discrimination Train Extinguish Test
N: Rc-P
L: Rc-P
R1-P
R2-P
L:R1-noP and
N:R2-noP
N: R1,
N: R2,
L: R1,
L: R2
• N = noise; L = Light; P = food pellet
• R1 = response lever; R2 = Chain Pull
Rescorla (1993)
• Prediction for weakened R-O association?
• Prediction for inhibitory S-O association?
• Prediction for inhibitory R-O association?
• Prediction for inhibitory S-R association?
Results

Partial Reinforcement Extinction Effect
• Responding continues longer following partial reinforcement than following
continuous reinforcement
• Explanations:
• Discrimination Hypothesis - transition from partial reinforcement to extinction is
less noticeable
Other explanations of the PREE
• Frustration Theory (Amsel)
• Initial training:
• Continuous Reinforcement
• Every response is reinforced
• Partial Reinforcement
• Not every response is reinforced
• Nonreinforcement produces frustration
• Continuing to respond in the presence of frustration is eventually reinforced
• Frustration acts as a discriminative stimulus
Frustration Theory
• Why do animals show the partial reinforcement extinction effect?
• During extinction animals experience frustration
• Animals that never previously experienced frustration (CRF) quit sooner than
animals that have been reinforced while experiencing frustration (Partial
reinforcement)