Georgia State University ScholarWorks @ Georgia State University Psychology Dissertations Department of Psychology 12-17-2015 An Investigation of Emergent Perceptual Phenomena in Primates: Illusions and Biases in Decision-Making Audrey E. Parrish Georgia State University Follow this and additional works at: https://scholarworks.gsu.edu/psych_diss Recommended Citation Parrish, Audrey E., "An Investigation of Emergent Perceptual Phenomena in Primates: Illusions and Biases in Decision-Making." Dissertation, Georgia State University, 2015. https://scholarworks.gsu.edu/psych_diss/146 This Dissertation is brought to you for free and open access by the Department of Psychology at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Psychology Dissertations by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact
[email protected]. AN INVESTIGATION OF EMERGENT PERCEPTUAL PHENOMENA IN PRIMATES: ILLUSIONS AND BIASES IN DECISION-MAKING by AUDREY E. PARRISH Under the Direction of Michael J. Beran, PhD, and Sarah F. Brosnan, PhD ABSTRACT The perceptual system operates ideally to reveal rapidly processed, accurate and functional information to an organism. However, illusory phenomena emerge when there is discontinuity between sensory input and perception on the basis of misleading contexts. Because illusions emerge as a byproduct of an otherwise functional and efficient perceptual system, they provide a means to understand better mechanisms of perception within and across species. Beyond anatomical and functional similarities in the visual system across primates, nonhuman primate species reveal intriguing similarities in the perception of visual illusions with one another and humans. This dissertation explored visual illusions across the Order Primates, including human adults and children, chimpanzees, rhesus monkeys, and capuchin monkeys, with a focus on when, why and for whom geometric illusions emerge.