This research examined the conditions necessary for pigeons to treat dissimilar objects as though the same. Earlier research showed that association with a common response was adequate (Wasserman, DeVolder, & Coppage, 1992). The present research examined association with a common delay to reinforcement as a potential category-binding event. Pigeons were trained with 24 photographs from each of four classes (people, flowers, cars, and chairs). The delay following C1 and C2 was 15 s, whereas the delay following C3 and C4 was 1 s. Different responses, R1 vs. R2, were then established to C1 and C3. Tests with familiar and novel stimuli established that association with a common delay linked pairs of categories. Pigeons predominantly chose R1 to C2 stimuli and R4 to C4 stimuli. In this study, nonhuman animals were able to conceptually categorize non-similar items, in that prior experience caused the subjects to act the same towards them.
Jennifer Hawkins, ’98
Sponsor: Suzette Astley