Reversal of preference under progressive-ratio schedules by punishment.
A small aversive tied to quitting can make learners accept bigger work loads.
01Research in Context
What this study did
Pigeons pecked a key that paid food on a progressive-ratio schedule. The ratio got bigger after each pellet.
A second key let the bird reset the ratio back to easy. The experimenter then added brief shock every time the pigeon hit reset.
They ran an ABAB reversal: shock on, shock off, shock on, shock off.
What they found
When shock punished the reset key, birds stopped hitting it. They stayed on the main key and finished more ratio steps.
When shock was removed, they quickly went back to resetting early. Punishment alone flipped their choice.
How this fits with other research
DARDANO et al. (1964) showed the same thing earlier: shock steers pigeons away from the punished side. The 1968 paper just made the punished side the "easy out" and saw the same avoidance.
Deluty (1976) seems to disagree. Rats actually increased pressing on a lever that was still shocked but less shocked than the other. The birds in 1968 never faced two shocked keys, so the clash is only skin-deep—both studies say animals pick the cheaper cost.
Santi (1978) adds a rule: punishment hurts lean-reinforcement behavior most. If your reinforcement is thin, even mild shock will push the client to escape.
Why it matters
Your client may "reset" tasks when work gets hard—asking for breaks, changing games, or hitting the tablet home button. A mild aversive tied to that escape (a firm "no," loss of tokens, or response cost) can keep them in the task longer. Watch reinforcement rates: if the task pays little, punishment will bite harder and the child may shut down completely.
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02At a glance
03Original abstract
A progressive-ratio reinforcement schedule, in which successive reinforcements required an additional 50 responses, was programmed on one key. A response on a second key reset the progressive-ratio schedule to the first step. Before punishment, all pigeons consistently reset the schedule after reinforcement on the first step, thereby minimizing the number of responses required for reinforcement. Punishment was a brief electric shock contingent upon each response on the reset key. The first effect of punishment was to change the frequency of extra responses on the reset key. Under higher intensities of punishment, the pigeons completed the advanced steps of the progressive-ratio schedule before resetting to the first step. Completions of advanced steps were accompanied by decreases in the overall rate of responding and the rate of reinforcement. When the punishment contingency was removed, the major features of pre-punishment performance were recovered.
Journal of the experimental analysis of behavior, 1968 · doi:10.1901/jeab.1968.11-133