A Test of an Auditory Motion Hypothesis for Continuous and Discrete Sounds Moving in Pitch Space
Total Page:16
File Type:pdf, Size:1020Kb
A TEST OF AN AUDITORY MOTION HYPOTHESIS FOR CONTINUOUS AND DISCRETE SOUNDS MOVING IN PITCH SPACE Molly J. Henry A Dissertation Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2011 Committee: J. Devin McAuley, Advisor Rodney M. Gabel Graduate Faculty Representative Jennifer Z. Gillespie Dale S. Klopfer ii ABSTRACT J. Devin McAuley, Advisor Ten experiments tested an auditory motion hypothesis, which proposes that regular pitch- time trajectories facilitate perception of and attention to auditory stimuli; on this view, listeners are assumed to use velocity information (pitch change per unit time) to generate expectations about the future time course of continuous and discrete sounds moving in pitch space. Toward this end, two sets of experiments were conducted. In six experiments reported in Part I of this dissertation, listeners judged the duration or pitch change of a continuous or discrete comparison stimulus relative to a standard, where the comparison’s velocity varied on each trial relative to the fixed standard velocity. Results indicate that expectations generated based on velocity information led to distortions in perceived duration and pitch change of continuous stimuli that were consistent with the auditory motion hypothesis; specifically, when comparison velocity was relatively fast, duration was overestimated and pitch change was underestimated. Moreover, when comparison velocity was relatively slow, duration was underestimated and pitch change was overestimated. On the other hand, no perceptual distortions were observed for discrete stimuli, consistent with the idea that velocity information is less clearly conveyed, or easier to ignore, for discrete auditory stimuli. Four experiments reported in Part II tested the hypothesis that listeners tune attention to expected pitch-time locations of future events based on velocity information conveyed by continuous and discrete auditory stimuli. Listeners detected pure-tone signals in noise that were expected or unexpected based on extrapolation of the trajectory of ascending or descending glides or sequences. Consistent with the auditory motion hypothesis, results indicate that listeners iii used pitch-time trajectory information in continuous and discrete auditory stimuli to tune attention; that is, listeners were most sensitive to detect expected relative to unexpected signals, and results were similar for continuous and discrete cues. However, consistent with an auditory gravity hypothesis, large asymmetries were observed for ascending versus descending cues, with listeners overshooting the expected pitch location of signals following descending cues. Taken together, the results support the hypothesis that listeners use velocity information to generate expectations about the future time course of sounds moving in pitch space. iv ACKNOWLEDGMENTS I have been lucky to have received an amazing amount of support through not only the completion of this manuscript, but in the years leading to up this point. It is my honor to be able to acknowledge those who have made my education a fun and fulfilling endeavor. First I must acknowledge the unconditional love and support that my family has given me all of my life. Without them, it is impossible to imagine myself doing what I am today. To my parents, Phil and Mary, and my brother, Paul: thank you and I love you. Also, to my cat Tweeker, who sat on my lap for a large portion of the time spent writing this dissertation, thanks. A million thanks are due to my advisor, Devin McAuley. It was by accident that I ended up in his lab, and I cannot imagine a better outcome. Devin has provided me with a challenging and productive work environment for the past five years that I believe has allowed me to realize my potential as a scientist. I have immensely enjoyed my time working and learning with Devin, and I look forward to our future interactions. Many thanks are also due to William Hartmann, professor of physics and head of the psychoacoustics lab at Michigan State University. Since I arrived at MSU just over a year ago, Bill has adopted me into his lab, allowed me use of his equipment and knowledge, and demonstrated infinite patience in his dealings with me. Bill was instrumental in completion of this manuscript, and for that he deserves many thanks. Thanks also to Tim Pleskac for much useful discussion regarding the simulations presented in this dissertation. I would like to acknowledge the support of my labmates, present and past, who have shared their knowledge, logged hours of useful discussion, and participated in non-scholastic activities that nonetheless make the scholastic hours more bearable. Laura Dilley, Nate Miller, and Louis Vinke deserve special mention in this regard. Laura Dilley has given me the opportunity to learn many skills, and has provided me with unfailing support and sound advice. v Nate Miller has provided me with meaningful advice and friendship through all of my graduate training. As an example of this, during these final weeks of manuscript preparation, Nate has sent daily emails containing ‘dissertation motivators’ to keep morale high. Finally, Louis Vinke has been a formidable ‘partner in crime’ in many shared adventures. Over the years, I have been helped by research assistants who all deserve mention, but are too numerous to name. Several that deserve special thanks are those who helped with data collection for the experiments contained in this dissertation. So thanks to Liza Kustantin, Ben Mastay, Brian Spyke, Neelima Wagley, Jon Walters, Alan Wedd, Amelia Wiggins, Phyllis Yan, and Lauren Zeilinski, I would also like to acknowledge the listeners who participated in Experiments 8, 9, and 10 of this dissertation, who each contributed a minimum of six hours to testing, mostly for an interest in science. Finally, thanks are due to the members of my committee, Dale Klopfer, Jen Gillespie, and Rod Gabel. The three of you have provided useful comments that have helped to shape this dissertation. vi TABLE OF CONTENTS Page INTRODUCTION …………………………………………………………………….... 1 PART I CHAPTER 1. PERSPECTIVES ON THE PERCEPTUAL INTERDEPENDENCE OF PITCH AND TIME .......……………………………………………………………….. 6 Perceptual Independence of Pitch and Time ......................................................... 8 Behavioral evidence for pitch-time independence ……………………... 8 Neural evidence for pitch-time independence ……………………... 11 Acquired amusia (lesion studies) …………………………....... 11 Neuroimaging studies ……………………………………………... 13 Summary ……………………………………………………... 16 Perceptual Interdependence of Pitch and Time ……………………………... 16 Behavioral evidence for pitch-time interdependence ……………………... 17 Neural evidence for pitch-time interdependence ……………………... 22 Auditory motion hypothesis ……………………………………………... 24 CHAPTER 2: APPLICATION OF THE AUDITORY MOTION HYPOTHESIS TO SOUNDS MOVING CONTINUOUSLY IN PITCH SPACE ……………………... 33 Experiment 1 ……………………………………………………………………… 36 Method ……………………………………………………………… 36 Design ……………………………………………………………… 36 Participants ……………………………………………………… 36 Stimuli and apparatus ……………………………………………… 36 vii Procedure ……………………………………………………… 37 Data analysis ……………………………………………………... 39 Results ……………………………………………………………………... 41 Imputed velocity model …………………………………………… 45 Summary ……………………………………………………... 45 Experiment 2 ……………………………………………………………………... 46 Method ……………………………………………………………... 46 Design ……………………………………………………………... 46 Participants ……………………………………………………... 46 Stimuli and apparatus ……………………………………………... 47 Procedure ……………………………………………………... 47 Results ……………………………………………………………………... 47 Imputed velocity model ……………………………………... 51 Summary ……………………………………………………... 52 Experiment 3 ……………………………………………………………………... 53 Method ……………………………………………………………... 53 Design ……………………………………………………………... 53 Participants ……………………………………………………... 53 Stimuli and apparatus ……………………………………………... 53 Procedure ……………………………………………………... 55 Results ……………………………………………………………………... 55 Imputed velocity model ……………………………………... 58 Comparison of results across standard velocities ……………... 58 viii Summary ……………………………………………………... 60 General Discussion ……………………………………………………………... 60 CHAPTER 3: EXTENSION OF THE AUDITORY MOTION HYPOTHESIS TO SOUNDS IMPLYING MOTION IN FREQUENCY SPACE ……………………… 67 Experiment 4 ……………………………………………………………………… 68 Method ……………………………………………………………… 68 Design ……………………………………………………………… 68 Participants ……………………………………………………… 68 Stimuli and apparatus ……………………………………………… 70 Procedure ……………………………………………………… 71 Results ……………………………………………………………………… 71 Imputed velocity model ……………………………………… 75 Summary ……………………………………………………… 75 Experiment 5 ……………………………………………………………………… 76 Method ……………………………………………………………… 76 Design ……………………………………………………………… 76 Participants …………………………………………………….... 77 Stimuli and apparatus ……………………………………………… 77 Procedure ……………………………………………………… 77 Results ……………………………………………………………………… 77 Imputed velocity model ……………………………………… 80 Summary ……………………………………………………… 80 Experiment 6 ……………………………………………………………………… 80 ix Method ……………………………………………………………… 80 Design ……………………………………………………………… 80 Participants …………………………………………………….... 80 Stimuli and apparatus ……………………………………………… 81 Procedure ……………………………………………………… 81 Results ……………………………………………………………………… 81 Imputed velocity model ……………………………………… 85 Comparison of results across standard velocities …………….... 85 Summary ……………………………………………………… 86 General Discussion ……………………………………………………………… PART II CHAPTER 4: ATTENTIONAL TUNING TO FREQUENCY AND TIME ………………