Document Type


Degree Name

Master of Arts (MA)




Faculty of Science

First Advisor

Angelo Santi

Advisor Role

Thesis Supervisor


The theoretical implications of the Scalar Timing Theory (STT) and the Mixed Memory Model were used as a paradigm to investigate the effects of stimulus properties on the psychological representation of time. Experiment 1 failed to demonstrate a Modality Effect in two sets of psychophysical tests using filled and empty intervals. Experiment 2 provided no evidence for a Filled Interval Illusion but the results from the acquisition phase and psychophysical tests indicated that, on some trials, rats forgot the presentation of the first marker of an empty interval. In Experiment 3, an Empty Interval Illusion was reliably demonstrated in three sets of psychophysical tests. A multiplicative difference in the PSEs supported a clock rate difference and the presence of mixed distributions in reference memory. Therefore, this study provided evidence for the STT with mixed memories under specific experimental conditions; however, this version of the STT was unable to account for all of the data from other experimental conditions.

Convocation Year


Convocation Season