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On the Role of Imputed Velocity in the Auditory Kappa Effect

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On the Role of Imputed Velocity in the Auditory Kappa Effect ON THE ROLE OF IMPUTED VELOCITY IN THE AUDITORY KAPPA EFFECT Molly J. Henry A Thesis Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of MASTER OF ARTS May 2007 Committee: J. Devin McAuley, Advisor Dale Klopfer Verner Bingman ii ABSTRACT J. Devin McAuley, Advisor The auditory kappa effect is a is a systematic effect of manipulations to pitch on judgments about auditory sequence timing. Two experiments were conducted to examine the role of imputed pitch velocity in the auditory kappa effect. In both experiments, participants judged the timing of a ‘target’ tone embedded in a three tone sequence (a kappa cell), while ignoring manipulations of the target’s pitch. Experiment 1 examined the effects of the presence/absence of a context sequence that reinforced the pitch velocity imputed to the kappa cell on the magnitude of the auditory kappa effect. Presence of a context sequence tended to weaken the kappa effect. Experiment 2 varied the pitch velocity of sequences between trials. Generalizing findings from vision, the magnitude of the auditory kappa effect increased as pitch velocity increased. Findings are discussed with respect to the perceptual interdependence of space and time. iii ACKNOWLEDGMENTS I would like to acknowledge the help and guidance provided by the Timing Research Group, specifically that of my advisor, J. Devin McAuley, and Laura Dilley. Thanks to Danielle Champney for a tremendous help with running participants and to Noah MacKenzie for answering all of my naïve questions. iv TABLE OF CONTENTS Page INTRODUCTION ……………………………………………………………………. 1 Auditory Kappa Effect ...................................................................................... 3 Imputed Velocity Hypothesis ............................................................................ 4 Local vs. Global Imputed Velocity .................................................................... 7 Overview ............................................................................................................ 9 EXPERIMENT 1 …………………………………………………………………….. 11 Method ............................................................................................................. 11 Design ................................................................................................... 11 Participants ............................................................................................ 11 Apparatus .............................................................................................. 12 Stimuli ................................................................................................... 12 Procedure .............................................................................................. 13 Data Analysis ........................................................................................ 14 Results ............................................................................................................... 16 Application of the Imputed Velocity Model ......................................... 17 Discussion ......................................................................................................... 18 EXPERIMENT 2 .......................................................................................................... 20 Method .......................................................................................................................... 20 Design ................................................................................................... 20 Participants ............................................................................................ 21 Apparatus .............................................................................................. 21 v Stimuli ................................................................................................... 21 Procedure .............................................................................................. 23 Data Analysis ........................................................................................ 24 Results .............................................................................................................. 25 Application of the Imputed Velocity Model ......................................... 27 Discussion ......................................................................................................... 28 GENERAL DISCUSSION ........................................................................................... 31 Perceptual Interdependence .............................................................................. 36 Tau Effect .............................................................................................. 36 Auditory Streaming ............................................................................... 37 Extrapolations Based on Constant Velocity and Acceleration/Deceleration ..................................................................... 38 Representational Momentum ................................................................ 39 Auditory Pattern Perception .................................................................. 42 Music and Speech ................................................................................. 42 Perceptual Independence .................................................................................. 45 Music Perception .................................................................................. 45 Amusia .................................................................................................. 45 Conclusions ....................................................................................................... 48 REFERENCES ............................................................................................................. 50 FIGURE CAPTIONS ................................................................................................... 55 APPENDIX A: TRAINING PROCEDURES .............................................................. 65 vi LIST OF FIGURES Figure Page 1 ............................................................................................................................. 57 2 ............................................................................................................................. 58 3 ............................................................................................................................. 59 4 ............................................................................................................................. 60 5 ............................................................................................................................. 61 6 ............................................................................................................................. 62 7 ............................................................................................................................. 63 8 ............................................................................................................................. 64 1 INTRODUCTION Time and space are abstract dimensions for which there exist neither stimuli nor receptors. The perceptual experience of movement requires the extraction and integration of information about transformations along both dimensions simultaneously. In general, transformations along the dimensions of time and space are coherently and lawfully related. The tendency towards regularity in space-time transformations undergone during movement allows for the mental extrapolation of the coherent space-time trajectory to an expected location of a future event. It has been proposed that the ability to dynamically predict the future location of a moving stimulus is the mechanism that allows a person to “cast out attentional thrusts” forward to ‘when’ in time and ‘where’ in space an event may be expected (Jones, 1981). A question can then be raised as to the nature of the connections between spatial and temporal information that yields a unified, holistic perceptual experience. An intriguing possibility is that time and space are inextricably linked, and thus perception along each dimension is dependent on the other. An example of such perceptual interdependence is the kappa effect, which is the focus of this thesis. The kappa effect is the dependence of the perceived timing of events on their relative spatial orientation. The kappa effect has been primarily studied in the visual modality (e.g. Cohen, et. al., 1953, 1955; Price-Williams, 1954; Matsuda & Matsuda, 1979, 1981; Jones & Huang, 1982; Huang & Jones, 1982; Sarrazin, et. al., 2004). The canonical method is as follows: Three stimuli (a kappa cell) are flashed sequentially; the first and third (bounding) stimuli remain fixed in space and in time across trials. The spatiotemporal position of the middle, ‘target’ stimulus is manipulated. The observer is asked to judge when the target occurs, ignoring where it is located. The kappa effect is a tendency for judgments of timing to be systematically influenced by the spatial position of the target. When the spatial extent delimited by two stimuli is 2 decreased, the corresponding time interval is often underestimated. Conversely, if the spatial extent between two stimuli is increased, the corresponding temporal interval is likely to be overestimated. Thus, duration judgments are dependent on the magnitude of the spatial separation between
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