Time allocation in concurrent schedules: the effect of signalled reinforcement.
A clear "reinforcer ready" cue can empty responding from that option, so watch your token boards and first-then visuals.
01Research in Context
What this study did
Pigeons pecked two keys. Each key paid off on its own timer. Sometimes a light came on to say, "Food is ready now on this key." The team watched where the birds spent their time.
They compared two set-ups: one with the food signal and one without. They also tried giving more food overall, then adding the signal again.
What they found
When the light announced food on Key A, the birds almost stopped pecking Key A. They moved to Key B, even if Key B paid less. The usual matching rule broke down.
Adding extra food before the signal fixed the problem. The birds spread their time normally again.
How this fits with other research
Marcucella (1976) saw the first hint. Full signals gave contrast; half signals gave the opposite. The new study shows full signals can kill responding entirely.
Jarrold et al. (1994) moved the same math to kids doing worksheets. Students also under-matched unless teachers added timers or delays. The bird lab and the classroom tell the same story: extra cues can override pay rate.
Duker et al. (1996) swapped signal for cheap candy. Low-quality prizes pushed kids away from the richer schedule, just like the light pushed pigeons away. Different tool, same drift.
Why it matters
Token boards, "first-then" cards, or any cue that shouts "reinforcer coming" can backfire. Clients may leave the task you want them to do. Before you add a big signal, test it. If time allocation drops, raise the pay-off or fade the cue. Check the data, not the toy.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Count minutes your client stays on task after you show the token board; if time drops, add more reinforcers or dim the signal.
02At a glance
03Original abstract
The responses of five pigeons were reinforced on concurrent variable-interval variable-interval reinforcement schedules in which changeover key responses changed the stimulus and reinforcement schedules associated with the food key. While the reinforcement availability in one component remained unchanged throughout the experiment, the reinforcement availability in the other component was, during several conditions, signalled by the onset of an additional discriminative stimulus. During unsignalled conditions, both the relative frequency of responding and the relative time spent in each component approximated the obtained relative reinforcement frequency in each component. The effect of signalling reinforcer availability in one component was to (1) reduce responding in the signalled component to near-zero levels, and (2) increase the relative time in the unsignalled component, without a corresponding increase in the obtained relative reinforcement frequency. The magnitude of the increase in relative time in the unsignalled component decreased as the overall frequency of reinforcement increased. This deviation in the matching relation between relative time and the obtained relative reinforcement frequency was eliminated if the overall reinforcement frequency was increased before the signal was introduced and then, without removing the signal, gradually reduced.
Journal of the experimental analysis of behavior, 1978 · doi:10.1901/jeab.1978.29-419