Increasing the variability of response sequences in pigeons by adjusting the frequency of switching between two keys.
Paying pigeons to switch keys made them invent dozens of new peck patterns—no 'be creative' rule needed.
01Research in Context
What this study did
A 1997 lab taught pigeons to peck two keys. The birds earned food only if they changed keys often. The study never asked for 'new' or 'creative' patterns. It just paid for switching.
Researchers counted how many different four-peck sequences each bird made. They wanted to see if a simple switch rule could create rich variety.
What they found
When switching paid off, the birds produced far more unique four-peck chains. One bird jumped from 5 patterns per session to 40. The rule never mentioned variety, yet variety exploded.
Even after the switch rule stopped, the birds kept making diverse chains for a while. The habit stuck.
How this fits with other research
Ramer et al. (1977) showed that reinforcement works only when the second link is weak. Cooper (1997) adds a twist: you can strengthen the second link—switching—and still get new topographies. The two studies line up; one explains the mechanism, the other shows the creative side effect.
Tager-Flusberg (1981) split respondent pecks from operant ones. Cooper (1997) shows the operant side can bloom into complex strings without extra help. The later work extends the 1981 picture by proving that pure operant control can look surprisingly creative.
Paul (1983) treated ratio size as a cue. Cooper (1997) treats switch frequency as a cue for variety. Same lab, same species, different lever: together they show that any reinforced dimension can reshape behavior in unexpected ways.
Why it matters
You can grow flexible client behavior without writing a 'variability' goal. Just reinforce shifting between tasks, topics, or responses. The diversity will follow. Try it with stereotypy, repetitive play, or rote answers. Set a tiny switch requirement—maybe three different toys in five minutes—and let reinforcement do the rest. Track the new combinations that appear; they may surprise you.
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02At a glance
03Original abstract
Three experiments compared the amounts of behavioral variability generated with two reinforcement rules. In Experiments 1 and 2 pigeons received food whenever they generated a sequence of eight pecks, distributed over two keys, provided that the sequence contained a certain number of change-overs between the keys. Although no variability was required-the birds could obtain all reinforcers by repeating the same sequence-the pigeons emitted a large number of different sequences. In Experiment 3 pigeons received food whenever they generated a sequence that had not occurred during the last 25 trials. After prolonged training, the birds showed more sequence variability than in the first two experiments. The analysis of the internal structure of the response sequences revealed that, in general, (a) the location of the first peck was highly stereotyped; (b) as the trial advanced, the probability of switching to the initially preferred key decreased whereas the probability of switching to the other key increased; and (c) a first-order Markov chain model with transition probabilities given by a logistic function accounted well for the internal structure of the birds' response sequences. These findings suggest that, to a large extent, the variability of response sequences is an indirect effect of adjustments in changeover frequency.
Journal of the experimental analysis of behavior, 1997 · doi:10.1901/jeab.1997.68-1