Temporal patterns of responding in small fixed-ratio schedules.
Small fixed-ratio schedules shorten, not lengthen, the post-reinforcement pause.
01Research in Context
What this study did
Crossman et al. (1985) looked at how pigeons respond when the ratio is tiny. They tested FR 1, 2, 3, 5 and 7. Each bird pecked a key for food.
They recorded every peck and the pause right after food. They wanted to see if the old "bigger ratio, longer pause" rule still holds for small numbers.
What they found
As the ratio grew from FR 1 to FR 7, the post-reinforcement pause got shorter, not longer. The birds also pecked faster early in the ratio.
The timing pattern flipped. Early pecks were quicker than the pecks just before food, the opposite of what big-ratio studies show.
How this fits with other research
Halpern et al. (1966) first showed that large FR schedules make pauses longer. Crossman et al. (1985) now show the rule reverses below FR 10.
Rider (1980) also found longer pauses with bigger ratios, but those ratios were much higher. The clash disappears when you see the range: small FRs behave differently.
Crossman et al. (1973) mixed large and small ratios. When large ratios were rare, pauses shrank. Together these papers draw a line: FR 10 is where the pause-length rule flips.
Why it matters
When you shape new skills with tiny ratios, expect no long pause. A client may start responding almost immediately after reinforcement. If you see a pause grow, the ratio has probably crossed into the teens. Use this flip as a live signal to adjust schedule size during teaching or maintenance sessions.
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02At a glance
03Original abstract
Pigeons were exposed to an ascending series of small fixed-ratio schedules from fixed-ratio 1 to 7. Two of those pigeons were later placed on a fixed-ratio 30 schedule. The two primary dependent variables were the postreinforcement pause and the interresponse time. Changes in these variables under small fixed ratios were sometimes opposite to changes reported with large fixed ratios. For example, postreinforcement pauses decreased in length as the fixed-ratio requirement increased from fixed-ratio 1 to fixed-ratio 3. Also, the interresponse times early in the small fixed-ratio schedule were shorter than those immediately preceding reinforcement. These findings question the role of interresponse-time reinforcement in determining temporal patterns of responding under small fixed-ratio schedules. They also suggest that there may be a limited region in which the independent variable, fixed-ratio size, does not operate as previously described.
Journal of the experimental analysis of behavior, 1985 · doi:10.1901/jeab.1985.43-115