An analysis of rats' drinking-tube contacts under tandem and fixed-interval schedules of food presentation.
Schedule layout alone can smooth or scatter the bonus behaviors you see between tasks.
01Research in Context
What this study did
Kohlenberg et al. (1976) watched rats drink from a tube while food arrived on fixed-interval or tandem schedules.
They counted how often the rats touched the tube and how steady the lever pressing looked.
The goal was to see if schedule shape, not just food rate, changes the way extra behaviors look.
What they found
Tandem schedules made lever presses more even and changed the way rats licked the tube.
Simple fixed-interval schedules gave jerkier, more scattered drinking bursts.
So the hidden structure of the schedule sculpted the form of the bonus behavior.
How this fits with other research
Jwaideh (1973) saw the same thing with lever pressing: tandem beats chained for smooth, steady work.
Catania et al. (1982) later showed that food vs water reinforcers also reshape approach moves, stretching the topography idea further.
Thomson (1974) first mapped chained FI pauses in pigeons; the 1976 rat study swaps species and adds drinking, a clean extension.
Hamm et al. (1978) found fixed-interval schedules make response location wander more, matching the variability seen here in drinking contacts.
Why it matters
If you want calm, predictable adjunct behavior, pick schedules that spread work evenly.
Try tandem or mixed schedules during long DTT breaks to keep stereotypy low and hands quiet.
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02At a glance
03Original abstract
Rats' lever presses and drinking-tube contacts were studied under fixed-interval schedules of food presentation and under a tandem schedule composed of three fixed intervals. One group of rats was exposed first to the tandem schedule, next to fixed-interval schedules of comparable interpellet intervals, and once again to the tandem schedule; a second group of rats was exposed first to a fixed-interval and then to the tandem schedule. Under the tandem schedule, lever presses occurred at a higher rate and were more uniformly distributed in time than under the fixed-interval schedule. Tube contacts emitted by rats exposed first to a fixed-interval schedule consisted mostly of tongue contacts, which occurred at a high rate shortly after food; tube contacts emitted by rats exposed first to the tandem schedule consisted mostly of paw contacts, which occurred at a lower rate at times other than shortly after food. Changing the schedule from fixed interval to tandem decreased the frequency of tongue contacts for all rats. Under schedules of food presentation with comparable interpellet intervals, the schedule of food presentation, rather than the rate of food delivery per se, determined the topography and temporal locus of drinking-tube contacts.
Journal of the experimental analysis of behavior, 1976 · doi:10.1901/jeab.1976.25-361