I What Influences the Relative Proportion of ‘Rigid Rotation’ Versus ‘Non-Rigid Deformation’ in a Bistable Stroboscopic Motion Display. Irene Rui Chen A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy School of Architecture, Design and Planning University of Sydney 2018 II Statement of Originality This is to certify that: I. The intellectual content of this thesis is the product of my own work towards the Doctor of Philosophy Degree II. Due acknowledgement has been made in the text to all other material used III. This thesis does not exceed the word length of this degree. IV. No part of this work has been used for the award of another degree V. This thesis meets research code of conduct requirements of the University of Sydney’s Human Research Ethics Committee (HREC), ethics reference number: 2013/562. Name: Irene Rui Chen III Abstract When observers are presented with a bistable stroboscopic display of an object that appears to transform over time in three-dimensional (3D) space, the dominance of one percept over another is influenced both by stimulus parameters and by cognitive factors. Two experiments were designed to reveal which of several manipulated variables influence most strongly which of two responses is more often observed, one being termed ‘Rigid Rotation’ and the other termed ‘Non-rigid Deformation.’ These two responses were clearly distinguished when drawings of a 3D rectangular box were presented stroboscopically in a two-frame animation with precise control over the Interstimulus Interval (ISI). In the first experiment, the relative dominance of the ‘Rigid Rotation’ response was reduced by changing the colour of one surface of the rectangular box in a manner that was inconsistent with the rotation of the box. Similarly, the relative dominance of the ‘Non-rigid Deformation’ response was reduced by changing the colour of one surface of the rectangular box in a manner that was inconsistent with deformation of the box. In the second experiment, the changes in the relative dominance of the competing motion percepts were observed after prolonged viewing of four different adapting stimuli. The adaptation aftereffects were shown to depend more upon the Interstimulus Interval (ISI) of the stroboscopic display of the adapting stimulus than upon what motion was reportedly ‘seen’ during the viewing of the adapting stimulus. Ultimately, the adaption aftereffect revealed that the relative dominance of the two movement percepts was affected most strongly by the manipulation of a single temporal variable – the ISI. Nonetheless, the results of the first experiment confirmed the influence of surface colour variations on ‘Rigid Rotation’ versus ‘Non-rigid Deformation’ responses. IV Acknowledgements I would like to extend my heartfelt gratitude to all those who have given assistance, encouragement and support throughout my PhD candidature. First and foremost, I would like to express my sincere appreciation to my supervisor, Associate Professor William L. Martens, for providing me with his expert direction, guidance and support through every stage of the thesis with concepts, suggestions, and criticisms over the last few years. Furthermore, I would like to express my gratitude to my copy editor Dr. Cherry Russell for reading, editing and commenting on my countless drafts. Without their contribution completion of this thesis would not have been possible. Secondly, special recognition to Professor David Alais in the department of psychology, University of Sydney, for providing his valuable advice and assistance during the early stage of the research. Thanks are also due to Associate Professor Wendy Davis for allowing me to use her lighting lab to conduct my experiments. Many thanks to the observers who voluntarily participated in all the experiments; without them the data collection would not have been possible. Special thanks to Dr Jennifer Gamble, Mr Stephen Broune and Mr David Haley, Mr Phil Davis, Mr Gary Jannese, and Dr Ali Khoddami, all of whom had faith in me and provided their support and comfort throughout this long journey. I would also like to extend my gratitude to various University of Sydney staff members, especially Associate Professor Paul Jones, Professor Richard de Dear, Ms Violeta Birks and Leslie George who offered understanding and support throughout my candidature. Also, I wish to acknowledge the support and encouragement from the research students in my office: Nickash Singh, Dheyaa Ali Hussein and Mansour Alulayet. Thank you for the discussion, help, encouragement and laughs. Special thanks to my oldest friend Mr Clive Evatt for his special humour and sarcasm that strengthened my determination to complete this long journey. V Last but not least, infinite thanks to my parents for their generous support, prayers and love throughout the struggles of this amazing journey, especially my mother for sharing the burden of caring for my sick father despite her own health issue, so I could work through the last stage of my thesis. This thesis is dedicated to them. Table of Contents: I Table of Contents Chapter 1: introduction ......................................................................................................... 1 1.1 Multistable Perception .......................................................................................................... 2 1.1.1 Still Images ................................................................................................................... 2 1.1.2 Stroboscopically Displayed Images .............................................................................. 5 1.2 Sensory Variables versus Cognitive Variables ................................................................... 7 1.3 Pre-attentive Processing and the Two-Process Model ..................................................... 11 1.4 Early Work on Apparent Motion ...................................................................................... 16 1.4.1 The Motion After-effect (MAE) ................................................................................. 18 1.4.2 Relation between 2D and 3D Structure in Motion ...................................................... 20 1.4.3 Recognition-by-Components and the Correspondence Problem ................................ 23 1.5 Perceptual Cycle .................................................................................................................. 27 1.5.1 Hypothesis .................................................................................................................. 29 1.6 Current Understanding of the Topic ................................................................................. 33 CHAPTER 2: LITERATURE REVIEW ......................................................................... 35 2.1 Multistable Apparent Motion ............................................................................................. 35 2.1.1 The Ternus Display .............................................................................................. ….36 2.2 Perceptual Organisation ..................................................................................................... 37 2.2.1 Central versus Peripheral Processes ......................................................................... 46 2.3 Studies of Motion After-effect (MAE) ............................................................................... 49 2.4 Association Field .................................................................................................................. 53 Table of Contents: II 2.5 The Rigidity Assumption .................................................................................................... 60 CHAPTER 3: RESEARCH METHODS ........................................................................... 63 3.1 Methods Common to the Two Experiments ................................................................... 63 3.2 Methodological Differences between the Two Experiments .......................................... 63 3.3 Methods .............................................................................................................................. 65 3.3.1 Observers .................................................................................................................. 65 3.3.2 Design ....................................................................................................................... 65 3.3.3 Stimulus generation and presentation ....................................................................... 66 3.3.3.1 Laboratory environment and apparatus………………………………………………………….66 3.3.3.2 Graphic image generation for rigid rotation and non-rigid deformation……………………67 3.3.3.3 Cycle duration……………………………………………………………………………………… .69 3.4 Procedure .......................................................................................................................... .70 3.5 Recording Methods and Results Calculations…………………………………………..73 CHAPTER 4: Experiment 1 ............................................................................................... 75 4.1 Method ............................................................................................................................... .75 4.1.1 Observers .................................................................................................................. 75 4.1.2 Design ......................................................................................................................