Further observations on overt "mediating" behavior and the discrimination of time.
Harmless collateral moves act as built-in timers during DRL schedules.
01Research in Context
What this study did
Scientists placed rats in a box with a lever.
The rats had to wait at least 14 seconds between presses to earn food.
While waiting, the rats began to nibble small wood chips.
The team then removed the chips to see what happened.
What they found
Without chips, the rats earned far fewer rewards.
Their nibbling had acted like a built-in timer.
When they could nibble, they spaced presses correctly.
How this fits with other research
Hansen et al. (1989) later showed the same idea works with children.
Kids who said the sample name aloud during a delay matched pictures better.
Both studies prove that simple side actions help bridge waiting time.
Vos et al. (2013) saw the flip side: when pigeons got no cue during a delay, response rates crashed.
Together the papers show that collateral behavior is not noise—it is a useful self-cue.
Why it matters
Let clients keep a quiet fidget while they wait.
A doodle, tap, or soft chant can become their timer.
You do not need extra equipment; the learner supplies the cue.
Next time you run DRL for calling out or hand raising, allow a harmless motor action and watch accuracy rise.
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02At a glance
03Original abstract
When the lever-pressing behavior of five rats was maintained by a DRL schedule (reinforcement was scheduled only when a specified waiting time between successive responses was exceeded), collateral behavior developed that apparently served a mediating function. In two cases this behavior did not arise until the experimental environment included pieces of wood that the rats started to nibble. When collateral behavior first appeared, it was always accompanied by an increase in responses spaced far enough apart to earn reinforcement. If collateral behavior was prevented, the number of reinforced responses always decreased. Extinction of lever pressing extinguished the collateral behavior. Adding a limited-hold contingency to the schedule did not extinguish collateral behavior. It appears that the rat can better space its responses appropriately when concurrently performing some overt collateral activity. The amount of this activity apparently comes to serve as a discriminative stimulus. To assume the existence of internal events that serve as discriminative stimuli in temporal discriminations is, at least under some circumstances, unnecessary.
Journal of the experimental analysis of behavior, 1969 · doi:10.1901/jeab.1969.12-43