title: Reflexivity in pigeons.
abstract: A recent theory of pigeons' equivalence-class formation (Urcuioli, 2008) predicts that reflexivity, an untrained ability to match a stimulus to itself, should be observed after training on two "mirror-image" symbolic successive matching tasks plus identity successive matching using some of the symbolic matching stimuli. One group of pigeons was trained in this fashion; a second group was trained similarly but with successive oddity (rather than identity). Subsequently, comparison-response rates on novel matching versus mismatching sequences with the remaining symbolic matching stimuli were measured on nonreinforced probe trials. Higher rates were observed on matching than on mismatching probes in the former group. The opposite effect--higher rates on mismatching than matching probes--was mostly absent in the latter group, despite being predicted by the theory. Nevertheless, the ostensible reflexivity effect observed in former group may be the first time this phenomenon has been demonstrated in any animal.
authors.affiliation: Purdue University, Department of Psychological Sciences, 703 Third Street, West Lafayette, IN 47907-2081, USA.
authors.forename: Mary M
authors.initials: MM
authors.lastname: Sweeney
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Urcuioli
mesh_terms: D000818:Animals; D001076:Aptitude; D001245:Association Learning; D001364:Awareness; D003118:Color Perception; D010856:Columbidae; D004193:Discrimination Learning; D005795:Generalization, Stimulus; D008297:Male; D009949:Orientation; D010364:Pattern Recognition, Visual; D011340:Problem Solving; D012055:Reinforcement Schedule; D012193:Reversal Learning; D013561:Symbolism