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Psychophysical Analysis of Three Separate Anisotropic Patterns in Vision University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 5-2017 Psychophysical analysis of three separate anisotropic patterns in vision : putting visual reference frames in conflict ot study the class 1 and 2 oblique effects and the horizontal effect. Eleanor O'Keefe University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Part of the Psychology Commons Recommended Citation O'Keefe, Eleanor, "Psychophysical analysis of three separate anisotropic patterns in vision : putting visual reference frames in conflict ot study the class 1 and 2 oblique effects and the horizontal effect." (2017). Electronic Theses and Dissertations. Paper 2631. https://doi.org/10.18297/etd/2631 This Doctoral Dissertation is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. PSYCHOPHYSICAL ANALYSIS OF THREE SEPARATE ANISOTROPIC PATTERNS IN VISION: PUTTING VISUAL REFERENCE FRAMES IN CONFLICT TO STUDY THE CLASS 1 AND 2 OBLIQUE EFFECTS AND THE HORIZONTAL EFFECT By Eleanor O’Keefe B.S., UC Santa Barbara, 2010 M.S., University of Louisville, 2013 A Dissertation Submitted to the Faculty of the College of Arts and Sciences of the University of Louisville In Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy in Experimental Psychology Department of Psychological and Brain Sciences University of Louisville Louisville, Kentucky May 2017 PSYCHOPHYSICAL ANALYSIS OF THREE SEPARATE ANISOTROPIC PATTERNS IN VISION: PUTTING VISUAL REFERENCE FRAMES IN CONFLICT TO STUDY THE CLASS 1 AND 2 OBLIQUE EFFECTS AND THE HORIZONTAL EFFECT By Eleanor O’Keefe B.S., UC Santa Barbara, 2010 M.S., University of Louisville, 2013 A Dissertation Approved on April 14, 2017 by the following Dissertation Committee: _____________________________ Dissertation Director Dr. Paul DeMarco _____________________________ Dr. Pavel Zahorik _____________________________ Dr. Heywood Petry _____________________________ Dr. Christian Stilp _____________________________ Dr. Martha Bickford ii ACKNOWLEDGEMENTS I would first like to acknowledge Dr. Paul DeMarco for his amazing support in enabling me to finish this project and receive my degree. I am especially thankful to Paul allowing me to continue the same dissertation project as well as helping me design the set-ups needed and make up the difference between project cost and my awarded grant funding. Many, many thanks to the other members of my dissertation committee: Dr. Pavel Zahorik, Dr. Heywood Petry, Dr. Christian Stilp, and Dr. Martha Bickford for taking their time to rigorously evaluate this project as well as answer my questions along the way. I would like to thank Dr. Edward Essock for inspiring the ideas behind this project. Thank you to all of the participants without whom I could not have gathered data, especially those who were available to participate in several conditions. Thanks to Dr. Kate Godwin, my previous lab mate who provided academic help and is a great friend. To Dr. Marci DeCaro who was an amazing TA advisor and helped me discover my love of teaching. Thank you to Dr. Cara Cashon who was always available to talk and for quick statistics questions. Thanks also to Dr. Edna Ross, Dr. Melinda Leonard, and Dr. John Pani who helped me with participant recruitment. Thank you to the Psychology department staff, especially Carla Gates, Diane Penrod and Kim Hosburgh. Thanks to the University itself and the Graduate school for making travel and project grants available and for graduate student appreciation week. To my parents who came out to visit at least once a year and gave me emotional support throughout the whole process. And lastly to my dog Samson, whose happy face greeted me at the door every day. iii ABSTRACT PSYCHOPHYSICAL ANALYSIS OF THREE SEPARATE ANISOTROPIC PATTERNS IN VISION: PUTTING VISUAL REFERENCE FRAMES IN CONFLICT TO STUDY THE CLASS 1 AND 2 OBLIQUE EFFECTS AND THE HORIZONTAL EFFECT Eleanor M. O’Keefe April 14, 2017 This dissertation describes and investigates a debate about differences in the visual system’s anisotropic sensitivity to orientation as well as where and how the brain encodes visual orientation information. Three different visual perceptual patterns are discussed: the Class 1 and 2 oblique effects and the horizontal effect. The oblique effect is the ability to perceive cardinal orientations more easily than oblique orientations, and is found using narrowband stimuli. In the horizontal effect, oblique orientations are perceived most easily, horizontal orientations are perceived worst, and vertical orientations fall in-between, and is found using broadband stimuli. While the majority of authors refer to the oblique effect as a whole, there is a case that it can be divided into Class 1 and Class 2 depending on what the task is measuring: low-level properties of the visual system or higher-level categorization and memory tasks. Moreover, when determining which reference frame the visual system uses to define the oblique effect, there is a disagreement as to whether it is the retinal or gravitational reference frame. To add evidence that there are two classes of the oblique effect and that they are defined by different reference frames (hence the disagreement), retinal, gravitational, and patterncentric coordinates were put in conflict with one another. The effects of phenomenological coordinates were also tested to determine whether top- iv down cognition played a role in either the Class 1 or Class 2 effect. That the Class 1 oblique effect remained defined by retinal coordinates no matter the test. The Class 2 oblique effect was defined by gravitational coordinates during head tilt with no available patterncentric information. However, when patterncentric coordinates were available the Class 2 effect pattern was defined by these coordinates. Phenomenological coordinates seemed to make no difference to either effect. These results add to current evidence that the oblique effect should be separated into two classes: Class 1, which shows the low-level orientation characteristics of the visual system and is defined by retinal coordinates, and Class 2, which is defined by patterncentric coordinates, and gravitational coordinates when there is no patterncentric input. There have been no studies to date to address the coordinates used by the visual system to define the horizontal effect. The horizontal effect is thought to be important for scene information, so the hypothesis was that it would follow patterncentric coordinates. Again, I tested retinal, gravitational, patterncentric, and phenomenological reference frames. During head tilt (no patterncentric information available), the standard horizontal effect did not remain tied to gravitational coordinates, nor did it transfer completely to retinal coordinates. The pattern did change completely with patterncentric coordinates during scene tilt, indicating that the horizontal effect is important for scene information. However, during scene tilt alone, retinal and patterncentric coordinates are aligned. During the head and scene tilt condition, when patterncentric and retinal coordinates are in competition, there was also incomplete transfer. Phenomenological changes seemed to have no effect. This suggests that the horizontal effect likely receives input from cortical v areas where some cells update their receptive fields when vestibular information changes, but some do not, such as V2 or V3. vi TABLE OF CONTENTS PAGE ACKNOWLEDGEMENTS………………………………………………………………iii ABSTRACT……………………………………………………………………………...iv LIST OF TABLES………………………………………………………………………..ix LIST OF FIGURES…………………………………………………………………….....x CHAPTER I: INTRODUCTION………………………………………………………...1 General Background on Vision……………………………………………………1 The Oblique Effect……………………………………………………………….10 Class 1……………………………………………………………………11 Class 2……………………………………………………………………16 The Horizontal Effect……………………………………………………………18 Visual Reference Frames………………………………………………………...23 Cortical implications……………………………………………………..33 CHAPTER II: GENERAL METHODS AND ANALYSES……………………………..35 General Methods…………………………………………………………………36 General Analyses………………………………………………………………...37 CHAPTER III: EXPERIMENT 1: CLASS 1 OBLIQUE EFFECT…………..…………38 Rationale…………………………………………………………………………38 Procedure………………………………………………………………………...38 Analyses………………………………………………………………………….41 Results……………………………………………………………………………41 Summary…………………………………………………………………………48 CHAPTER IV: EXPERIMENT 2: CLASS 2 OBLIQUE EFFECT…………..…………51 Rationale…………………………………………………………………………51 Procedure………………………………………………………………………...51 Analyses………………………………………………………………………….53 Results……………………………………………………………………………53 Summary…………………………………………………………………………60 CHAPTER V: EXPERIMENT 3: THE HORIZONTAL EFFECT………………………63 vii Rationale…………………………………………………………………………63 Procedure………………………………………………………………………...64 Analyses………………………………………………………………………….65 Results……………………………………………………………………………66 Summary…………………………………………………………………………75 CHAPTER VI: GENERAL DISCUSSION………………...……………………………79 Experiment 1……………………………………………………………………..79 Experiment 2……………………………………………………………………..82 Experiment 3……………………………………………………………………..85 General Conclusions……………………………………………………………..88
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