Schedule-induced drinking: rate of food delivery and Herrnstein's equation.
Schedule-induced drinking follows the same matching law as operant behavior, so one equation can predict both.
01Research in Context
What this study did
Wetherington (1979) worked with lab rats. Food came on a fixed-time schedule. Water was always there.
The team watched how fast the rats drank. They plugged the numbers into Herrnstein’s equation. This is the same math we use for lever pressing.
What they found
The drinking data made a smooth curve. The curve fit Herrnstein’s hyperbola. Adjunctive behavior obeyed the matching law just like operant behavior.
How this fits with other research
Kazdin (1977) showed the matching law works when rats choose between wheel running and sugar water. Wetherington (1979) extends that idea to schedule-induced drinking.
Allison (1976) saw drinking drop when lever pressing paid more. He used conservation theory. L used matching theory instead. Same behavior, different math.
Smith et al. (1975) found drugs changed drinking in odd ways. L kept drugs out and showed the clean curve underneath.
Why it matters
You now have one equation for two worlds: operant and adjunctive. If your client paces and sips water, you can model both acts with the same formula. Try plotting the data. The curve may tell you which behavior will win when schedules shift.
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Join Free →Count sips per minute while food or praise comes on a fixed clock, then graph it and see if the curve fits Herrnstein’s hyperbola.
02At a glance
03Original abstract
Schedule-induced drinking was measured in four rats exposed to fixed-time schedules of food ranging from 30 to 480 seconds. Herrnstein's (1970, 1974) equation relating rate of a single response as a hyperbolic function of reinforcement rate provided a good fit to three measures of drinking: lick rate, ingestion rate, and relative time spent drinking. The functions relating the three measures of drinking to reinforcement rate were of similar form. Herrnstein's equation also provided a good description of some already published data on schedule-induced drinking. The fit both to the present data and to the already published data was improved somewhat by computing the measures by subtracting from the time base a latency constant representing the minimal time required to consume the food pellet and travel to the water source. The data from this study provide two correspondences between operant behavior and schedule-induced behavior: (a) conformity to Herrnstein's equation and (b) equivalence of rate and relative time measures.
Journal of the experimental analysis of behavior, 1979 · doi:10.1901/jeab.1979.32-323