The blocking of reinforcement control.
An available side response during a delay can steal reinforcement power and kill the target response.
01Research in Context
What this study did
The team set up a simple lever task. Pressing it once started a delay.
During the wait another lever that already paid off sat nearby.
They asked: does this extra lever steal the value of the first one?
What they found
Yes. When the second lever was there, the first lever stopped working.
Some subjects quit pressing it altogether. The extra response blocked reinforcement.
How this fits with other research
Vos et al. (2013) later saw the same drop without any extra lever. Just waiting hurt the rate.
Eisenmajer et al. (1998) added that even a three-second silent wait slashes how much the reinforcer is worth.
Leon et al. (2016) looked brighter: with humans, food delayed up to 20 s still kept some responding. The damage is real but not always total.
Why it matters
If you run DRO, token boards, or any delay, watch what the client can do while waiting. A toy, a phone, or even a glance at another staff member can soak up the value you meant for the target skill. Either deliver the reinforcer right away or make sure only the target response earns it.
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02At a glance
03Original abstract
Two experiments were conducted to extend the blocking effect to the reinforcement of a response. A delayed reinforcement contingency was presented to subjects with or without a previously pretrained response available during the delay interval. The interpolated response had no scheduled effect on delivery of the reinforcer, but its availability reduced strengthening of the initial response, which completely extinguished for some subjects. The results were interpreted as support for blocking as a fundamental principle of behavior, and as evidence against the principle of reinforcement being stated solely in terms of temporal proximity between response and reinforcer.
Journal of the experimental analysis of behavior, 1975 · doi:10.1901/jeab.1975.24-215