A contingency interpretation of Place's contingency anomaly in ordinary conversation.
Listener replies can work like reinforcers in a behavior chain, so sentence variety grows when novelty gets the payoff.
01Research in Context
What this study did
Leigland (2000) wrote a theory paper. He asked why people keep varying their sentences in everyday talk. He mapped each sentence as a link in a chain. The listener's reply is the reinforcer for that link.
He wanted to show that ordinary listener nods, laughs, or answers work just like food pellets in a lab. The chain view keeps everything inside standard reinforcement rules.
What they found
The paper argues that variability grows because the next speaker's response is the payoff. Different words can still earn the same smile. The speaker keeps trying new forms until the listener reacts.
No new rule is needed. The old three-term contingency still holds when you see the whole chain.
How this fits with other research
Catania (2021) tested the idea in a lab. He looked for trial-to-trial carry-over of response details. He found none. This extends Leigland (2000) by showing that the reinforcer picks the class, not the exact form.
Coe et al. (1997) asked how close in time a reinforcer must be. Leigland (2000) answers for talk: the listener's next turn is close enough, even if it is seconds away.
Hall (1992) showed pigeons pecking random sequences when the schedule paid for novelty. The same rule explains why humans keep varying sentences. Both studies put variability under contingency control, just in different species.
Why it matters
When you teach conversation skills, think in chains. The learner's sentence is only half the story. Program the partner's reply as the reinforcer. If you want more varied speech, reinforce novel forms. If you want stable answers, reinforce the same form. Watch the next turn; that is the pellet.
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02At a glance
03Original abstract
A verbal phenomenon often reported in the research literature of conversation analysis is reviewed. The phenomenon involves the observation that spoken sentences often receive consequences from listeners, and that the effect of these consequences appears to be variability in sentence emission, whereas the absence of such consequences appears to produce response persistence. If the speaker's sentences function as units of verbal behavior and the listener's responses function as reinforcers, the effect seems to run contrary to reinforcement contingency effects observed in the laboratory, where reinforcement produces response differentiation and extinction produces an increase in response variability and a decrease in the response class previously selected by reinforcement. An interpretation of the conversation phenomenon is presented, employing standard reinforcement contingencies for which the behavioral dynamics involved may be seen when speaker's sequence of sentences is construed as a behavior chain.
The Analysis of verbal behavior, 2000 · doi:10.1007/BF03392962