Year of Award


Document Type


Degree Type

Doctor of Philosophy (PhD)

Degree Name

Experimental Psychology

Department or School/College

Department of Psychology

Committee Chair

Wendy Shields

Commitee Members

Allen Szalda-Petree, Nabil Haddad, Stuart Hall, Irene Appelbaum


duration discrimination, metacognition, rats, tones, uncertainty monitoring


University of Montana


Comparative psychologists have explored the metacognitive capabilities of rhesus monkeys, a capuchin monkey, an orangutan, a dolphin, pigeons, and rats. Previous research with rats has demonstrated inconsistent results (Foote & Crystal, 2007; Smith & Schull, 1989). In the current study, two Sprague-Dawley rats were tested in a tone-length discrimination task in which they were prompted to press one of two levers indicating "short" or "long" depending on the duration of a tone. They also had the option to opt out of some trials. If the subjects knew when they did not know the answer to the task, they were expected to opt-out more frequently as the difficulty of the task increased. They were also expected to demonstrate differences in accuracy for trials during which they could opt-out and trials in which they could not opt-out. Higher accuracies were expected on trials during which they could opt-out. One subject did not select the opt-out option during testing. The other subject did not use the opt-out option adaptively by opting out more as the difficulty of the stimulus discrimination increased. However, when comparing trials in which the subjects could not opt-out and those in which the subjects could opt-out, this subject demonstrated higher accuracies on trials in which he could opt-out. This provides some evidence that at least one rat knows when he does not know the answer to a duration-discrimination task. This experiment imparts clarification to previous research and provides further evidence for uncertainty monitoring among rats, lending greater understanding to the evolutionary development of uncertainty monitoring.



© Copyright 2010 Leslie Anne Angel