Chained concurrent schedules: reinforcement as situation transition.
Reinforcement is the doorway to the next activity, and learners will match their responses to how often that door opens.
01Research in Context
What this study did
Baer (1974) worked with pigeons on chained concurrent schedules.
The birds could peck two keys. Each peck could move them to the next link or deliver food.
The team watched how often the birds pecked each key during the first link.
What they found
In the first link, the birds’ peck ratios matched the ratios of situation changes.
When the right key led to the next link twice as often, they pecked it twice as much.
In the final links, the matching faded and the birds pecked more equally.
How this fits with other research
Varley et al. (1980) extends this idea. They showed that just changing the light color between links made pigeons peck faster. The change itself acted like a treat.
Bejarano et al. (2007) adds a twist. They tied the transition to the bird’s own timing. Transitions still worked as reinforcers even when normal delay rules failed.
Together, the three papers say: moving to a new situation is reinforcing. The later studies keep the core idea but add new rules about when the move matters most.
Why it matters
You can think of reinforcement as a doorway, not just a snack. When a client finishes a worksheet and you point to the play area, that point is a transition cue.
If you want to boost a response, raise the chance that the response opens the next door. Use clear signals for the shift—lights, words, or a gesture. The doorway itself becomes the reward.
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Join Free →Signal each step change with a unique cue—like a colored card—and watch response ratios shift toward the cue that opens the next link more often.
02At a glance
03Original abstract
Pigeons' pecks at two white response keys (initial-link situation) occasionally turned both keys red (terminal-link situation). When the two keys were red, pecks occasionally produced food, after which the keys were again white. In both situations, a changeover delay prevented the response-produced outcome from immediately following a change of responding from either key to the other. In the initial-link situation, the ratio of pecks at the keys closely paralleled the ratio of transitions into the terminal-link situation produced by the pecks, conforming to the well-known matching relation. In the terminal-link situation, the peck ratios deviated from the matching relation toward indifference. Overall response rate and rate of changeover were generally higher in the terminal-link situation than in the initial-link situation. The finding of matching in the initial-link situation supports a definition of reinforcement as situation transition. The differences in performance between the two situations, viewed in the light of other recent findings, suggest that the effects of a changeover delay depend on the overall reinforcing value of the choice alternatives.
Journal of the experimental analysis of behavior, 1974 · doi:10.1901/jeab.1974.22-91