The effects of fixed‐interval schedules on variability of pigeons' pecking location
Longer fixed-interval schedules make pigeons peck all over the key, not just in one spot.
01Research in Context
What this study did
Kono (2017) worked with pigeons on fixed-interval schedules. The birds pecked a key for food every 30, 60, or 120 seconds.
The team tracked exactly where on the key each peck landed. They wanted to see if the wait time changed the spot the bird hit.
What they found
As the interval got longer, the pigeons' pecks spread out. The birds also drifted toward the place that had just paid off.
Shorter intervals kept the pecks tight and steady. Longer intervals made the landing spots more scattered.
How this fits with other research
Whitehead et al. (1975) showed that if you remove the peck-food link on FI, the scallop flattens. Kono adds that even when the link stays, longer FIs still loosen control—this time in space, not rate.
Hassin-Herman et al. (1992) found pigeons quickly reset wait times when short FIs changed daily. Kono shows the same quick adjustment happens to peck location, linking temporal and spatial control.
Fantino (1969) saw pauses stretch across long-interval runs. Kono’s spatial drift lines up: longer FIs make both timing and location wobble more.
Why it matters
If you run FI schedules with clients, watch where the response happens, not just when. Longer waits may make the response top less consistent. Shorten the interval or add spatial cues to keep the response form tight.
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Place a small visual cue on the target spot and shorten your FI to 30 s to keep responses accurate.
02At a glance
03Original abstract
Many studies that have investigated performance under reinforcement schedules have measured response rate or interresponse time, which reflect the temporal dimension of responding; however, relatively few studies have examined other dimensions. The present study investigated the effects of fixed-interval schedules on the location of pigeons' pecking response. A circular response area 22.4 cm in diameter was used so that the pecking responses were effective over a wide range. Pigeons were exposed to a fixed-interval schedule whose requirement was systematically varied between conditions. Response location moved closer to the location of the last reinforced response as time elapsed in each trial. Additionally, as the fixed-interval duration requirement increased, response locations shifted to the border of the response area and the variability of response locations increased. These results suggest that fixed-interval schedules systematically control response location.
Journal of the Experimental Analysis of Behavior, 2017 · doi:10.1002/jeab.276