title: The object-line inferiority effect in pigeons.
abstract: Eight pigeons (Columba livia) were trained to discriminate between diagonal lines presented alone or embedded in a redundant L-shape right-angle form. The stimuli were white and were presented in an environment that was otherwise totally dark. Numerous experiments done with human observers have shown a strong superiority effect when the diagonal lines are embedded in redundant contexts. However, in Experiment 1 of the present study, the pigeons discriminated significantly better between the two diagonal lines when presented alone than when they were embedded in the right-angle context. In order to check on the possibility that these results were restricted to the semi-Ganzfeld condition of Experiment 1, a second experiment was done with black stimuli presented on a white background. Results of Experiment 2 also showed a strong distractor effect. The results of the present experiments confirmed the predictions of the Heinemann and Chase model of pattern recognition by pigeons.
authors.affiliation: Brooklyn College, City University of New York.
authors.forename: F J
authors.initials: FJ
authors.lastname: Donis
authors.forename: E G
authors.initials: EG
authors.lastname: Heinemann
mesh_terms: D000818:Animals; D001288:Attention; D010856:Columbidae; D004193:Discrimination Learning; D005260:Female; D008297:Male; D011939:Mental Recall; D009949:Orientation; D010364:Pattern Recognition, Visual