Document Type


Degree Name

Master of Arts (MA)




Faculty of Science

First Advisor

Angelo Santi

Advisor Role

Thesis Supervisor


There is evidence to suggest that pigeons will actively encode information on delayed matching-to-sample (DMTS) tasks either by maintaining a representation of the sample stimulus during the retention interval (retrospective processing) or by maintaining a representation of the response decision in anticipation of the upcoming comparison stimuli (prospective processing). The following experiments were conducted to determine whether processing in DMTS is retrospective or prospective in nature. Using a paradigm developed by Stonebraker (1981), pigeons were simultaneously trained on two types of tasks: identity and symbolic matching. Only one set of sample stimuli was used and followed by either the symbolic or identity comparison set. Instructional stimuli immediately followed the termination of the sample stimulus in the first experiment. These stimuli predicted the upcoming comparison set (identity or symbolic matching) on that particular trial. On probe trials the comparison sets were either incorrectly cued or not cued at all. In a second experiment the instructional stimuli were presented at the beginning, middle, and end of the retention interval on probe trials. In addition, the comparison sets were correctly, incorrectly, or not cued. The data presented for these experiments favour a retrospective interpretation of information processing.

Convocation Year


Convocation Season


Included in

Ornithology Commons