INFLUENCING ORAL-NASAL BALANCE IN SPEECH AND SONG by Charlene Holly Santoni A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Faculty of Music University of Toronto © Copyright by Charlene Holly Santoni 2021 Influencing Oral-Nasal Balance in Speech and Song Charlene Holly Santoni Doctor of Philosophy Faculty of Music University of Toronto 2021 Abstract Oral-nasal balance is dependent on the valving of the velopharyngeal sphincter. This dissertation examined the control and modification of oral-nasal balance in speech and song. Literature was reviewed from the fields of speech science and singing voice pedagogy, which motivated three projects. The first project (Santoni et al., 2018) explored the role of altered nasal signal level feedback on the regulation of oral-nasal balance in singing in trained and untrained singers. Results indicated that all participants showed lower nasalance scores in response to both increased and decreased nasal signal level feedback. The findings implied that trained singers’ internal models for controlling oral-nasal balance may not be as refined as those that guide other vocal parameters. The second project (Santoni et al., 2019) explored the influence of voice focus adjustments (forward and backward vocal tract shape and length modifications) (Boone, 2007; Boone et al., 2010) on the control of oral-nasal balance in typical speakers in speech and song. Results indicated that forward focus led to higher and backward focus to lower nasalance scores. There was one exception wherein one female participant produced lower nasalance scores in forward focus during the nasal stimulus. The results confirmed that voice focus maneuvers influence oral-nasal balance in typical speakers. Findings from project 2 led to the clinical experiment described in project 3. ii The third project (Santoni, Thaut & Bressmann, 2020) explored the influence of voice focus adjustments on the control of oral-nasal balance in speakers with hypernasality in speech and song. Results indicated that for a group of five speakers with hypernasality, forward focus resulted in higher and backward focus resulted in lower nasalance scores. There was one exception wherein one male participant produced lower nasalance scores in forward focus during the nasal stimulus. The results provided preliminary evidence that voice focus maneuvers influence oral-nasal balance in speakers with hypernasality. With further development of the voice focus method, the intervention could become a useful therapeutic approach for speakers with hypernasality. Keywords: resonance, oral-nasal balance, velopharyngeal sphincter, nasality, hypernasality, cleft palate, nasalance, auditory feedback, compensation, voice focus, chiaroscuro, speech language pathology, singing voice pedagogy, voice therapy. iii Preface This thesis consists of studies that were designed with the support of members of the thesis committee, who contributed their disciplinary, analytical, pedagogical and clinical expertise to assist with the development of questions to which defined each of the three projects that make up this dissertation. Committee members (Dr. Michael Thaut, Dr. Tim Bressmann and Prof. Lorna MacDonald) reviewed and provided feedback for different parts of this manuscript. The PhD candidate is the primary author and contributor to all three projects, designing objectives and methodology, completing data extraction and analyses, and preparing and revising the manuscripts. iv Harmonia: an agreement of sounds. v Acknowledgments “…the best way to ‘know’ a thing is in the context of another discipline.” (Leonard Bernstein, The Unanswered Question: Six Talks at Harvard, 1973). What an enormous priviledge to have been able to complete an interdisciplinary PhD that brought together the fields of speech science and singing voice pedagogy. I am filled with immense gratitude and indebted to a number of people for making it possible. First and foremost, to my supervisors, to whom I am eternally grateful. To Dr. Tim Bressmann: I owe so much of my thanks to you. Thank you for believing in the music student with so many enthusiastic ideas about how to bridge singing and speech language pathology. Thank you for the masterful apprenticeship in voice research, for challenging me to step outside of my comfort zone, for our insightful discussions about oral-nasal balance, and for always keeping me focused. Most of all, thank you for sharing what you know with me and for truly caring about my success. To Dr. Michael Thaut. Thank you for your extraordinary wealth of inspirational accomplishment related to translational research in music and rehabilitation. You opened up a world of possibility to me. Thank you for seeing the spark in my eye when I spoke about singing and voice rehabilitation, for nurturing that ambition, for encouraging me to do clinical work, and for always vouching for my abilities. To my PhD committee member and lifelong mentor Prof. Lorna MacDonald. Thank you for revealing the wonderful world of vocal pedagogy and voice science to me; it became a true love of mine. I can still remember poring over that first pedagogy textbook you gave me years ago (the Doscher book) every chance I got. Thank you also for never wavering in your support of my creative and often wildly ambitious ideas, and for always championing my work. To my PhD examiners Dr. Paolo Campisi and Dr. Jamie Perry. Thank you as well for your careful review of my work. To my additional mentors, all of whom had a hand in my earning this degree. To my beloved voice teacher Dr. Mary Morrison. You are without question, one of the great singing teachers of our time and learning from you has been an honour that I will forever cherish. One of the most profound things you ever said to me was: “I’m proud of you because you took a risk.” Thank you for your wisdom, for your unconditional support and for being the kind of teacher that I will always strive to be. To Dr. Darryl Edwards. Thank you for your invaluable mentorship and for always encouraging me with such heartfelt and unwavering enthusiasm. Thank you most of all vi for being the person that suggested: “What if you did a PhD?” You changed the course of my life. To Dr. Corene Hurt-Thaut. Thank you for impressing upon me that I had something unique to offer and for giving me my first platform with which to engage in music-inspired voice rehabilitation. On a more personal level, thank you for sharing with me that you too completed a PhD with little children at home and that it was possible! Your support meant so much. To my labmates at MaHRC and in the Voice and Resonance Lab for their kindred friendship, especially Monique (who patiently taught me how to use all of the lab equipment), Telma, Varsha, Jenni, Catherine, and Nicole. Most importantly, to my very best lab friend Dr. Gillian de Boer. Thank you for always being excited about my work, for sharing your passion for research and statistics with me, for talking through ideas with me, and for reminding me to take care of myself. Without question, the projects that make up this thesis would not have been possible without all of my study participants, so thank you to each of them as well, especially the children and staff at Five Counties Children’s Centre. To my family for all of the immeasurable ways in which they have supported and encouraged me throughout my years of study. To my husband Dan (my other half). Your unwavering faith in my abilities is something that I needed in my life and will treasure forever. I can always picture your admiring face and recall your invaluable advice when I need to. Thank you for reminding me that it’s a marathon, not a sprint, and for repeating this phrase to me so often during my years of graduate study: “You can do it, and no matter what, we love you.” I love you too – so very much. To my son Oliver who was such a blessed surprise in the midst of graduate school and who allowed me a peaceful period in my life with which to discern the kind of work I wanted to do. To my son Jonas, our most recent family blessing. Thank you for being such a good napper so I that could finish my revisions, and for being the boost I needed to see this through to the end. To my twin sister Lesley, my partner on this journey. Who knew that during a global pandemic, the twins would both be awarded PhD’s? Lesley, I knew you could do it, and you knew I could do it, and that made all the difference. To my Mom and Dad who were always the first to stand up and yell “Brava” at my concerts and who always had something incredibly motivating to say when I felt discouraged. Thank you for raising a wildly ambitious daughter vii with a lot of passion, grit and determination – I share this accomplishment with you. To my grandparents who were always excited to hear about my latest adventures. You would have gotten a real kick out of this. I miss you every day. To the rest of my family and countless friends (too many to name) who checked in over the years to ask how it was going and wished me well. Thank you. Most of all, thank you to God who set out this path for me all along. “I can do all things through Christ who strengthens me.” (Philippians 4:13). Two closing thoughts: Some years ago, I taught a young girl with an intricate composite of vocal dysfunction to sing. My work with her in fact drove me to this work. Thank you SF, I will forever be indebted to you. Finally, during the course of my graduate study, I had the immense priviledge to meet and converse at a research conference with Dr.