Intermittent reinforcement of a continuous response.
Surprise keeps continuous behavior alive; fixed rules create longer pauses.
01Research in Context
What this study did
The team worked with lab rats.
Each rat had to hold down a small lever.
The rule for getting food kept changing.
Sometimes the rat had to hold for a fixed time.
Other times the time changed unpredictably.
The researchers timed how long each hold lasted.
They also timed the pause right after food delivery.
What they found
Variable hold times kept the rats pressing longer.
Fixed hold times made the rats pause more after food.
In plain words, surprise keeps the work going.
Steady rules slow the next start.
How this fits with other research
de Carvalho et al. (2018) got the same pattern with two rats pressing together.
Variable-ratio kept the pair working smoothly.
Fixed-ratio created stop-and-go teamwork.
Clarke et al. (1998) saw the opposite with teens who have severe ID.
Fixed-ratio tokens cut stereotypy better than variable-interval.
The difference is the task.
The rat studies looked at keeping a motion alive.
The classroom study looked at stopping a motion.
Same schedules, different goals.
Why it matters
If you want a client to stay on task longer, build in surprise.
Use variable praise, variable tokens, or variable check-ins.
Save fixed schedules for when you need to stop a behavior.
Match the schedule to the goal, not to the species.
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02At a glance
03Original abstract
Six rats were trained with food deliveries contingent upon their pressing a lever and holding it down for either fixed or variable cumulative durations. Fixed-hold requirements ranged from 15 s to 90 s over experimental conditions; variable-hold requirements ranged from 15 s to 120 s. At most long and intermediate values, variable-hold requirements maintained more lever holding than fixed requirements. At the longest hold requirements studied, more lever holding was maintained by variable requirements than by fixed requirements of equivalent mean length for each rat. Postreinforcement-pause duration increased with lever-holding time for both fixed- and variable-hold requirements. At comparable lever-holding times per reinforcer, longer pauses typically were produced by fixed requirements than by variable requirements. Data from this study on the maintenance of responding, temporal response patterns, and postreinforcement pausing are comparable to those obtained with intermittent reinforcement of discrete responses. These findings suggest that the response-reinforcer relation specified by a reinforcement schedule is a fundamental determinant of responding, whether responding consists of discrete units or of continuous activity.
Journal of the experimental analysis of behavior, 1987 · doi:10.1901/jeab.1987.47-81