Discriminative responding on associated mixed and multiple schedules as a function of food and ICS reinforcement.
ICS makes mixed-schedule discrimination crisper than food, so reinforcer choice can sharpen stimulus control.
01Research in Context
What this study did
The team ran mixed and multiple schedules with squirrel monkeys.
They compared two reinforcers: food pellets versus ICS (intracranial stimulation).
The question was simple—does reinforcer type change how well the animals tell the schedules apart?
What they found
ICS produced sharper discrimination than food.
Monkeys responded faster in the presence of the SΔ when ICS was on the line.
The result says reinforcer quality can strengthen stimulus control.
How this fits with other research
Morse et al. (1966) and McKearney (1970) ran multiple schedules with shock instead of food.
They got the same basic pattern—schedule structure ruled, not the reinforcer.
Together the four papers show: schedule design sets the frame, but reinforcer type tunes the clarity.
Aragona et al. (1975) later showed that contrast effects also hinge on what you remove—milk versus pellets.
The 1969 finding is the first brick in that wall.
Why it matters
If you use mixed or multiple schedules in treatment, think about what the client is working for.
A highly preferred edible or activity may tighten discrimination between work time and break time.
Try swapping in a stronger reinforcer when you need the client to notice the SΔ or schedule change.
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02At a glance
03Original abstract
Performance on associated mixed and multiple variable-interval-extinction schedules was studied as a function of food versus intracranial stimulation (ICS) reinforcement. For the mixed schedule, differential responding was greater for an ICS reinforcement group than for a food reinforcement group, demonstrating that conditions affecting resistance to extinction help to determine the control exerted by a mixed schedule. Performance on the multiple schedule demonstrated greater differential responding for an ICS group than for a food reinforcement group during the early training sessions, indicating that the control exerted by mixed schedules interacts with that exerted by the exteroceptive discriminative stimuli. The results suggest that the influence of the associated mixed schedule on discriminative responding would be greater, the greater the difficulty of the stimulus discrimination.
Journal of the experimental analysis of behavior, 1969 · doi:10.1901/jeab.1969.12-933