The effect of variable delays on self-control.
Mix up wait times instead of keeping them fixed to help clients stick with delayed rewards.
01Research in Context
What this study did
Researchers worked with pigeons in a lab.
The birds picked between two keys. One key gave a small treat right away. The other gave a bigger treat after a wait.
Sometimes the wait for the big treat was always 10 s. Other times it jumped around, say 5 s, then 15 s, then 10 s. The team counted how often the birds chose to wait.
What they found
Pigeons picked the larger, later snack more often when its wait time varied.
Fixed waits made the birds give up and take the quick, small reward.
How this fits with other research
Cicerone (1976) saw the same thing first: pigeons like mixed delays better than steady ones. Rojahn et al. (1994) now show this liking also boosts self-control.
Calamari et al. (1987) asked if choices stay logical when delays vary. They found the birds stayed consistent, so the new result is not due to messy decisions.
Davison et al. (1995) repeated the test with starlings. The birds again preferred variable delays, showing the rule crosses species.
Why it matters
When you teach a client to wait for a bigger reinforcer, do not lock the wait at one number. Shuffle the wait around a narrow range. The slight unpredictability can make waiting easier and strengthen self-control without extra toys or tokens.
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Join Free →Pick a preferred item, offer a bigger portion after variable waits (e.g., 5 s, 15 s, 10 s), and track if the client waits more often than with a fixed 10 s delay.
02At a glance
03Original abstract
Five pigeons served as subjects in an experiment that examined the effects of variable as opposed to fixed delays on preference in a self-control paradigm (choice between larger, more delayed and smaller, less delayed reinforcers). Nonindependent concurrent variable-interval schedules were used to measure choice. When delays to the larger, more delayed reinforcers were variable as opposed to fixed, the subjects showed an increased preference for that alternative (the self-control alternative). A series of regressions revealed that the hyperbolic decay model and incentive theory provided poor fits to the data, but a modified version of the generalized matching law provided an adequate fit. Together, consistent with a general prediction made by discounting models, the data supported the conclusion that variable delays can increase self-control. However, specific discounting models were not able to explain the present data well.
Journal of the experimental analysis of behavior, 1994 · doi:10.1901/jeab.1994.62-33