Some temporal parameters of non-contingent reinforcement.
Non-contingent reinforcement reliably cuts responding, and the thinner the baseline payoff, the less NCR you need.
01Research in Context
What this study did
Horner (1971) tested how non-contingent reinforcement (NCR) changes behavior. Pigeons pecked for food on three different schedules. Then the feeder dropped free food every 30, 60, or 120 seconds, no pecking needed.
The team used an ABAB design. Baseline, then NCR, then back to baseline, then NCR again. They watched how fast the birds pecked under each free-food plan.
What they found
Free food cut pecking the most when the baseline schedule paid little. Birds on rich schedules kept pecking more. The 30-second NCR hurt rates the hardest.
Response drops were steady, not sudden. When NCR stopped, pecking bounced back. The pattern held across all birds.
How this fits with other research
Rey et al. (2020) ran long DRO sessions and also saw big response drops. Both studies show that withholding response-linked food quiets behavior, even when the food still arrives on a clock.
Hursh et al. (1974) gave pigeons free food just like Horner (1971), but asked a different question: will the birds start pecking anyway? Most did not. Together the papers prove that response-independent food rarely creates new behavior, yet reliably cuts existing behavior.
Badia et al. (1972) showed that only differential reinforcement builds stimulus control. Horner (1971) adds the flip side: once behavior is running, non-differential free food can safely slow it down without building wrong stimulus control.
Why it matters
When you use NCR to reduce problem behavior, match the schedule to the client’s baseline reinforcement rate. If the child gets lots of attention for screaming, a dense NCR (like 30 s) will work faster. If attention is already thin, you can run a leaner schedule and still see results. Always probe first to know your baseline density.
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Join Free →Count baseline reinforcers per hour, then pick an NCR interval that is half that rate and run a quick reversal probe.
02At a glance
03Original abstract
In each baseline session, pigeons were exposed to a multiple schedule in which each of five distinctive stimuli was correlated with a different frequency of reinforcement. In one component, responses were reinforced with a probability of 0.10 (random-ratio schedule); in the other four components, responses were reinforced with different scheduled temporal frequencies averaging 30 to 240 sec between reinforcements (random-interval schedules). For periods lasting 30 sessions, contingent reinforcement was discontinued and reinforcement was presented independent of responding at irregular intervals averaging 30, 60, or 120 sec, while the sequence of stimuli continued. After each such period, the baseline was reinstated for 30 sessions. The data indicated that: (1) The rate of responding in the presence of all stimuli decreased as exposure to the non-contingent reinforcement procedure was prolonged, at all the frequencies of reinforcement employed; (2) The rate under the random-ratio schedule declined faster than the rates under all the random-interval schedules, presumably because the decrease in reinforcement frequency under this stimulus condition was greatest; (3) The decline in rates of responding under the stimuli correlated with the random-interval schedules tended to be greatest for the stimuli paired with the lowest frequencies of reinforcement.
Journal of the experimental analysis of behavior, 1971 · doi:10.1901/jeab.1971.16-207