Mechanisms of Avian Memory for Lateral and Frontal Visual Information

• Main Author: Murphy, Matthew S
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01.01.2014
• Subjects: Behavioral Sciences; Cognitive psychology; Experimental psychology
• ISBN: 9781321266665; 1321266669

Birds have multiple fovea-like areas for lateral and frontal vision, which have unique perceptual, anatomical, and cognitive properties. Prior research found an asymmetry with intraocular transfer between the visual fields within the same eye, specifically finding evidence of lateral-to-frontal transfer but not frontal-to-lateral transfer. This suggests that birds have separate lateral and frontal long-term memory systems. We isolated the visual fields using a unique behavioral targeting technique during visual memory tasks with pigeons. In one set of tasks, we trained pictures exclusively in the frontal or lateral fields, and pictures that sequentially appeared in both fields. We then transferred the single-field conditions to the other visual field of the retina (i.e., lateral pictures tested in the frontal field, and vice versa). We found the first evidence of frontal-to-lateral transfer, indicating that information from each visual field is accessible when tested in the other field. In a second set of experiments, we put into conflict the response mappings of identical pictures presented separately in the lateral and frontal fields, and compared performance between incongruent and congruent response mappings. Incongruence did not greatly impair accuracy, indicating that the pigeons effectively contextualized the lateral and frontal information. We suggest that birds have a common long-term visual memory system for frontal and lateral information, but are able to encode both item-specific and contextual information, allowing them to perform well in both the transfer tasks and the incongruent tasks.