Some relations between classically conditioned aggression and conditioned suppression in squirrel monkeys.
Offering an aggressive outlet can either sharpen or soften conditioned suppression, so check the individual data.
01Research in Context
What this study did
Stokes et al. (1980) worked with squirrel monkeys in a lab cage.
Each monkey first pressed a lever for food.
A red light then came on.
After the light, the monkey got a brief shock.
Sometimes a rubber bite tube hung in the cage.
Sometimes it was absent.
The team compared how much lever pressing dropped with and without the tube.
What they found
When the bite tube was present, results were messy.
Some monkeys bit the tube and pressed the lever less.
Others bit little and kept pressing.
Simple "biting competes with pressing" did not fit the data.
The tube changed both aggression and suppression in ways that shifted across sessions.
How this fits with other research
Schroeder et al. (1969) showed that a shock given right after a bite quickly stops hose biting.
Their effect was clean and large.
Stokes et al. (1980) used the same species and shock, yet saw mixed outcomes.
The difference is the bite tube was only an option, not a punished response.
Thomas et al. (1968) mapped how stronger shocks make monkeys bite more.
Stokes et al. (1980) add that simply giving the mouth something to bite can either soak up or spark that aggression, so suppression rises or falls.
Together the papers warn: the same aversive stimulus can suppress or release behavior depending on what responses are handy.
Why it matters
If a client hits or bites when tasks get hard, do not assume blocking the response will always calm them.
Providing a safe chew or squeeze ball may help some learners, yet trigger others.
Run a quick A-B-A probe: record task engagement with and without the alternative item.
Let the data tell you whether the item competes with or fuels the problem response.
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02At a glance
03Original abstract
During three experiments with squirrel monkeys, stimulus and shock pairings were given in the presence of a bite tube. Experiments 1 and 2 used a conditioned-suppression procedure in which bar pressing was reinforced with food. A transparent shield prevented biting of the bar. When the stimulus was paired with shock, bar pressing decreased (conditioned suppression) and tube biting increased during the stimulus (classically conditioned aggression). When the bite tube was removed on alternate sessions in Experiment 2, there was more suppression when the tube was present, thus suggesting that biting competed with bar pressing. However, this simple competing-response interpretation was complicated by the findings of Experiment 3 where, with naive monkeys, bar pressing was never reinforced with food, yet bar pressing was induced during the stimulus and was highest when the bite tube was absent. The fact that stimulus-induced bar pressing developed inciated that bar pressing in conditioned-suppression procedures, suppressed or not, may be maintained by two types of control--the food reinforcer and induced CS control. The higher rate of induced bar pressing during the stimulus with the bite tube absent confounds a simple competing response interpretation of conditioned suppression. It suggests that shock-induced responses during conditioned suppression could be both contributing to and competing with responding maintained by food, with the net effect depending on specific but ill-defined features of the situation.
Journal of the experimental analysis of behavior, 1980 · doi:10.1901/jeab.1980.34-149