Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Psychological Sciences

First Advisor

Peter J. Urcuioli

Committee Chair

Peter J. Urcuioli

Committee Member 1

James Nairne

Committee Member 2

Robert Proctor

Committee Member 3

Thomas S. Redick


Currently, the emergent relation of reflexivity after training a set of baseline relations has not been demonstrated with any animal—human or nonhuman. True reflexivity can only be demonstrated if no identity (i.e., physically matching stimulus) relations are trained. In six experiments, the emergence of reflexivity and its opposite, anti-reflexivity, were explored. Pigeons received concurrent successive matching training on two or three arbitrary tasks: AB hue-form and BC form-hue (and AC hue-hue) matching. Once they had acquired these tasks, they were tested for BB (form-form) reflexivity or BB’ (form-form) anti-reflexivity matching. Most (10 of 13) pigeons that received three arbitrary tasks showed reflexivity and some (4 of 17) showed anti-reflexivity. Eight pigeons trained on only two arbitrary tasks generally did not show evidence for emergent BB matching: Two showed reflexivity and one showed anti-reflexivity. Tests for stimulus class reorganization yielded mixed results. None of six pigeons demonstrated emergent anti-reflexivity after first showing emergent reflexivity, but three of five pigeons demonstrated emergent reflexivity after first showing emergent anti-reflexivity. In addition to these novel effects, the data indicate that stimulus class formation depends upon both the baseline contingencies and an apparent identity bias.