Concurrent fixed-ratio fixed-interval performances in adult human subjects.
Smaller ratio requirements speed up human interval responding, but the benefit stops when the ratio gets too big.
01Research in Context
What this study did
Adults pressed a button for money on two schedules at once.
One schedule paid after a set number of presses (FR). The other paid after a set time (FI).
The researchers watched how changing the FR size altered FI pressing.
What they found
Smaller FR sizes made people press faster during the FI part.
The pattern matched animal studies, but people never paused after payoff.
No ratio strain showed up, even when the FR grew.
How this fits with other research
Rider (1980) ran the same FR-FI setup eleven years later and saw the same link: smaller FR boosts FI rate.
Rapport et al. (1982) added the FR requirement inside the FI, not beside it. They still found FR size shifts FI responding, and showed that slow FI starters gain the most.
Lea (1976) pushed further, letting the FR grow across sessions. Once the ratio got too big, FI rates crashed—showing the boost has a ceiling.
BERRYMAELLIOTT et al. (1962) did the first FR-FI continuum with rats. The break-run pattern they saw in animals appears in humans too, but without the post-reinforcement pause.
Why it matters
When you mix ratio and interval schedules, the ratio size acts like a throttle on interval responding. Keep the ratio small if you want steady, fast responding during the interval part. Watch for a tipping point—too large a ratio can choke the whole pattern.
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02At a glance
03Original abstract
Two undergraduate males worked for money on a button-pressing task associated with concurrent fixed-ratio fixed-interval schedules of reinforcement. Manipulations of the fixed-ratio requirement produced an interaction between the various fixed-ratio and fixed-interval performances. When the fixed ratio was small, more fixed-interval responding occurred per interval than when the fixed ratio was large. In general, the data were similar to those obtained with lower organisms except that no post-reinforcement pause or ratio strain was seen.
Journal of the experimental analysis of behavior, 1969 · doi:10.1901/jeab.1969.12-601