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FLASH LAG EFFECT MODEL DISCRIMINATION.Pdf FLASH LAG EFFECT MODEL DISCRIMINATION A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy By STEPHEN REA GABBARD M.S. Wright State University 1994 M.B.A. Jacksonville University 1984 M.E.Ch.E. Clemson University 1981 Honors B.A. Rollins College 1975 2013 Wright State University WRIGHT STATE UNIVERSITY GRADUATE SCHOOL JULY 29, 2013 I HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER MY SUPERVISION BY Stephen R. Gabbard ENTITLED Flash Lag Effect Model Discrimination BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy. Scott N.J. Watamaniuk, Ph.D. Dissertation Director Scott N.J. Watamaniuk, Ph.D. Graduate Program Director Debra Steele-Johnson, Ph.D. Chair, Department of Psychology R. William Ayres, Ph.D. Interim Dean, Graduate School Committee on Final Examination Valerie Shalin, Ph.D. Alan Nagy, Ph.D. Robert Patterson, Ph.D. Abstract Gabbard, Stephen R., Ph.D., Human Factors and Industrial/Organizational Psychology Ph.D. Program, Department of Psychology, Wright State University, 2013. Flash Lag Effect Model Discrimination. The purpose of this study was to test the various models describing the Flash Lag Effect (FLE). Beginning with the initial work of Nijhawan (1994), several models have emerged endeavoring to explain the FLE (e.g., Eagleman & Sejnowski, 2000; Whitney, 2000; Baldo & Caticha, 2005). Two series of studies comprising 11 separate experiments were undertaken to differentiate these models, with a particular focus on the neural network model of Baldo and Caticha (2005). The experiments included the three primary FLE experimental paradigms: continuous motion (CM), flash-initiated (FIC) and flash- terminated (FTC). Ninety-three participants made observations in these three paradigms using a 2-AFC interleaved staircase protocol. ANOVAs were performed on each of the 11 experiments to determine main effects and interactions of the experimental factors, and additionally, overall FLE levels irrespective of factor influences. The combination of results shows that the neural network model (Baldo & Caticha, 2005) holds promise to form the basis for a unifying theory, whereas the postdiction (Eagleman & Sejnowski, 2000) and differential neural latency (Whitney, 2000) models do not. Implications and directions for further study are discussed. iii Contents Flash Lag Effect Model Discrimination ............................................................................. 1 Interactions of position determination and motion processes ..................................... 5 The Flash Lag Effect ................................................................................................. 10 Flash Lag Configurations .......................................................................................... 11 Generalized Interaction of Motion upon Position Determination ............................. 13 Theories Explaining the Flash Lag Effect ..................................................................... 15 Motion Extrapolation ................................................................................................. 20 Differential Neural Latency ....................................................................................... 23 Postdiction ................................................................................................................. 26 Motion Bias ............................................................................................................... 27 Attention .................................................................................................................... 29 Facial Chimera Anomaly ........................................................................................... 30 Foveopetal / Foveofugal anisotropy .......................................................................... 31 Neural Computational Model .................................................................................... 32 Neural Net Model Predictions in FIC ........................................................................... 35 Hypotheses and Research Questions ............................................................................. 37 Hypothesis 1 .............................................................................................................. 37 Hypothesis 2 .............................................................................................................. 37 Hypothesis 3 .............................................................................................................. 38 Hypothesis 4 .............................................................................................................. 38 Hypothesis 5 .............................................................................................................. 38 Hypothesis 5a ............................................................................................................ 39 Hypothesis 6 .............................................................................................................. 39 Research Question ..................................................................................................... 40 Narrative Summary of Experimental Series and Outcomes.......................................... 41 Experiments ................................................................................................................... 42 General ....................................................................................................................... 42 Experimental Series 1 ................................................................................................ 43 iv Apparatus - General ...................................................................................................... 44 Procedure - General ....................................................................................................... 44 Experiment 1 – Reaction Time .................................................................................. 45 Experiment 2-L: Continuous motion FLE 1 – (CM1) ............................................... 46 Experiment 2-L: Continuous motion FLE 2 (CM2) .................................................. 49 Experiment 3-S: Flash-initiated FLE – spatial (FIC-S) ............................................. 50 Experiment 3-T: Flash-initiated FLE-temporal (FIC-T) ........................................... 51 Experiment 4-S: Flash-terminated FLE-spatial (FTC-S) .......................................... 52 Experiment 4-T: Flash-terminated FLE-temporal (FTC-T) ...................................... 53 Preliminary Data Analysis Series 1 ............................................................................... 54 Transition from Experimental Series One to Series Two ............................................. 55 Experimental Series Two Description........................................................................... 58 General Apparatus ..................................................................................................... 59 Procedure for Experiment Series 2................................................................................ 59 Procedure - General ................................................................................................... 60 Experiment 1 – Reaction Time .................................................................................. 61 Experiment 2-L: Continuous Motion FLE 1 (CM1) ................................................. 61 Experiment 3-S: Flash-Initiated FLE – Spatial (FIC-S) ............................................ 62 Experiment 3-T: Flash-Initiated FLE-Temporal (FIC-T) .......................................... 64 Experiment 4-S: Flash-Terminated FLE-Spatial (FTC-S) ........................................ 65 Experiment 4-T: Flash-Terminated FLE-Temporal (FTC-T) ................................... 66 Data Analysis ................................................................................................................ 67 Results Experiment Series 1 .......................................................................................... 68 Experiment 1 – Reaction Time .................................................................................. 68 Experiment 2-Sp Continuous Motion FLE 1 – (CM1) .............................................. 69 Experiment 2-L – Continuous-Motion FLE 2 (CM2) ............................................... 70 Experiment 3-S: Flash-Initiated FLE – Spatial (FIC-S) ............................................ 71 Experiment 3-T: Flash Initiated FLE-Temporal (FIC-T) .......................................... 75 Experiment 4-S – Flash-Terminated FLE-Spatial (FTC-S) ...................................... 76 Experiment 4-T: Flash-Terminated FLE-Temporal (FTC-T) ................................... 78 Results Experiment Series 2 .......................................................................................... 79 v Experiment 1 – Reaction Time .................................................................................. 79 Experiment 2-L – Continuous-Motion FLE (CM) .................................................... 80 Experiment 3-S – Flash Initiated FLE – Spatial (FIC-S) .......................................... 81 Experiment 3-T: Flash-Initiated FLE – Temporal (FIC-T) ....................................... 83 Experiment 4-S: Flash-Terminated Condition Spatial Flash Lag ............................
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