Brown, G. S. & White, K. G. (2005).
On the effects of signaling reinforcer probability and magnitude in delayed matching to sample.
Journal of the Experimental Analysis of Behavior, 83, 119-128.
Two experiments examined whether postsample signals of reinforcer probability
or magnitude affected the accuracy of delayed matching to sample in pigeons.
On each trial, red or green choice responses that matched red or green stimuli
seen shortly before a variable retention interval were reinforced with wheat access.
In Experiment 1, the reinforcer probability was either 0.2 or 1.0 for both red and
green responses. Reinforcer probability was signaled by line or cross symbols that
appeared after the sample had been presented. In Experiment 2, all correct
responses were reinforced, and the signaled reinforcer durations were 1.0 s
and 4.5 s. Matching was more accurate when larger or more probable reinforcers
were signaled, independently of retention interval duration. Because signals
were presented postsample, the effects were not the result of differential
attention to the sample.
Key words: signaled magnitude effect, reinforcement probability, attention,
delayed matching to sample, pigeon