Behavioral momentum and accumulation of mass in multiple schedules.
Several stable-reinforcement sessions are required to build behavioral momentum; brief exposure fails.
01Research in Context
What this study did
Cox et al. (2015) worked with pigeons on two-key multiple schedules.
Each daily session switched between red and green lights.
One color always paid 15 pellets per minute; the other paid only 2.
The team varied how many days each color kept its rate before extinction tests.
What they found
After five or more days of steady pay, the rich key took longer to stop in extinction.
If the same pay had been stable for only one or two days, resistance vanished.
Brief exposure is not enough; momentum needs several consecutive stable sessions.
How this fits with other research
Craig et al. (2019) extend this point. They show that each new extinction probe weakens momentum. So one long stable history helps, but repeated probes still wear it down.
Fisher et al. (2018) apply the rule to therapy. They give clients many dense reinforcements for a replacement response before thinning. This builds momentum and cuts later resurgence.
Craig et al. (2016) look at the flip side. They changed pay rates every day and saw faster extinction. Stable history matters more than just a rich history.
Why it matters
When you shape a new skill, keep the reinforcement rate high and unchanged for several sessions before you thin. One good day is not enough. Expect faster drops after breaks or schedule changes if the history was short or choppy. Plan re-probes instead of trusting first-extinction data.
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02At a glance
03Original abstract
Behavioral momentum theory suggests that the relation between a discriminative-stimulus situation and reinforcers obtained in that context (i.e., the Pavlovian stimulus-reinforcer relation) governs persistence of operant behavior. Within the theory, a mass-like aspect of behavior has been shown to be a power function of predisruption reinforcement rates. Previous investigations of resistance to change in multiple schedules, however, have been restricted to examining response persistence following protracted periods of stability in reinforcer rates within a discriminative situation. Thus, it is unclear how long a stimulus-reinforcer relation must be in effect prior to disruption in order to affect resistance to change. The present experiment examined resistance to change of pigeon's key pecking following baseline conditions where reinforcer rates that were correlated with discriminative-stimulus situations changed. Across conditions, one multiple-schedule component arranged either relatively higher rates or lower rates of variable-interval food delivery, while the other component arranged the opposite rate. These schedules alternated between multiple-schedule components across blocks of sessions such that reinforcer rates in the components were held constant for 20, 5, 3, 2, or 1 session(s) between alternations. Resistance to extinction was higher in the component that most recently was associated with higher rates of food delivery in all conditions except when schedules alternated daily or every other day. These data suggest that resistance to change in multiple schedules is related to recently experienced reinforcer rates but only when multiple-schedule components are associated with specific reinforcer rates for several sessions.
Journal of the experimental analysis of behavior, 2015 · doi:10.1002/jeab.145