Generalization of color by chickens: experimental observations and a Bayesian model

Baddeley, R J, Osorio, D and Jones, C D (2007) Generalization of color by chickens: experimental observations and a Bayesian model. American Naturalist, 169 (S1). S27-S41. ISSN 0003-0147

PDF - Published Version
Download (520kB) | Preview


Sensory generalization influences animals' responses to novel stimuli. Because color forms a perceptual continuum, it is a good subject for studying generalization. Moreover, because different causes of variation in spectral signals, such as pigmentation, gloss, and illumination, have differing behavioral significance, it may be beneficial to have adaptable generalization. We report on generalization by poultry chicks following differential training to rewarded (T+) and unrewarded (T−) colors, in particular on the phenomenon of peak shift, which leads to subjects preferring stimuli displaced away from T−. The first three experiments test effects of learning either a fine or a coarse discrimination. In experiments 1 and 2, peak shift occurs, but contrary to some predictions, the shift is smaller after the animal learned a fine discrimination than after it learned a coarse discrimination. Experiment 3 finds a similar effect for generalization on a color axis orthogonal to that separating T+ from T−. Experiment 4 shows that generalization is rapidly modified by experience. These results imply that the scale of a “perceptual ruler” is set by experience. We show that the observations are consistent with generalization following principles of Bayesian inference, which forms a powerful framework for understanding this type of behavior.

Item Type: Article
Additional Information: The copyright of this publication is owned by The University of Chicago.
Keywords: chicken, color vision, peak shift, Bayesian, generalization
Schools and Departments: School of Life Sciences > Biology and Environmental Science
Subjects: Q Science > QZ Psychology
Q Science > QL Zoology
Depositing User: Daniel ColacoOsorio
Date Deposited: 24 Jul 2008
Last Modified: 09 May 2018 15:57
Google Scholar:12 Citations

View download statistics for this item

📧 Request an update