Wasserman, E. A., Young, M. E., & Peissig, J. J. (2002).
Brief presentations are sufficient for pigeons to discriminate arrays of same and different stimuli.
Journal of the Experimental Analysis of Behavior,
78, 365-373.
Four pigeons first learned to discriminate 16-item arrays of same
from different pictorial stimuli. They were then tested with
reduced exposure to the pictorial arrays, brought about by
changes in the stimulus viewing requirement under fixed-ratio
(FR) and fixed-interval (FI) schedules. Increasing the FR
requirement enhanced discriminative performance up to 10 pecks;
increasing the FI requirement enhanced discriminative performance
up to 5 s. Exposures to the stimulus arrays averaging only 2 s
supported reliable discrimination. Pigeons thus discriminate same
from different stimuli with considerable speed, suggesting that
same–different discrimination behavior is of substantial
adaptive significance.
Key words: same–different discrimination, sample duration,
fixed-interval schedules, fixed-ratio schedules, pecking, pigeons