My permanence in Sweden was only made possible through a generous and stimulating scholarship from the Brazilian Ministry of Education and Sports, through Capes Foundation. Also a special permission was given to me by the Rio de Janeiro Federal University to take leave from my position at the School of Music. I am grateful to my dear colleagues, particularly those from Department IV, who helped me in pursuing my doctoral studies. I shall do my best to return all this investment and solicitude by means of a passionate and dedicated work.

Once in Sweden, I would like to thank Gunnar Fant for establishing this renowned, innovative, interdisciplinary and harmonious Department of Speech, Music and Hearing, and for giving me the privilege of his friendship and enriching daily contact.

This thesis would not exist at all without Johan Sundberg, who accepted me as a doctoral student, despite my time constraints, and who believed in my project and in my declaration of dedication. His knowledge, guidance, energy, humour, friendship, openness, companionship and inspiration will always serve to me as an example of the perfect supervisor. In addition, his poetic talent for doing, writing and teaching science was highly inspiring and influential in this work. Johan has shown that being a supervisor is not only looking from above (which is not problem for him), but includes kindly taking the student by the hand (as implied by the Swedish term "handledare") and also having the gift of human and musical auscultation. Besides, being his co-author has been a great joy and privilege. In addition, it was marvellous to meet Ulla, Johanna, Bellen, Martin and Erik.

I would like to thank the former Head of Department, Björn Granström, for welcoming me and letting me into the institution. My heartfelt thanks also to the present "prefekt", Anders Askenfeld, for our great friendship and for gently "kicking me out" in a timely manner. Leaving this marvellous place is not an easy task. Also an effusive "tack" to all my colleagues and friends at the department for making this most intense triennium of my life an equally pleasant and unforgettable time, especially during the almost 150 Friday-coffee-breaks in which I happily parttook.

I would particularly like to thank Anders Askenfelt, Johan Liljencrants, Erik Jansson, Arne Lejon and Knut Guettler for sharing their profound knowledge and for participating in the different stages of this research and learning process. The course on scientific writing, given by Sandra Brunsberg, was most helpful and pleasant, and I hope this text is worthy of her approval.

Many thanks to my colleagues and friends at the music group for all the fun and collaboration: Jenny, Monica, Sten, Anders, Roberto/Christine, Sofia, Peta, Svante (who also helped so much in discussions and technical matters), Daniel, Julieta, Vittorio and Frédérique.

Special gratitude is devoted to Eric Prame, who accepted me as a roommate and who kindly and patiently helped me with so many practical details. His competent and meticulous review of this manuscript was invaluable. Moreover, his knowledge, reasoning, vivid interest on vast areas and emanating peacefulness were also a great help to me.

Once inside the room, I must thank whoever built my computer, Intruder; it never abandoned me and never distinguished between boring and exciting tasks. Obviously, my friends Svante, Jan, Tor and Kenneth are among the reasons for this flawless behaviour.

My life at the department was extremely facilitated by the work and friendship by Cathrin (who edited a great part of this thesis), Markku (who fixed everything but my computer), Viktoria and Armid (both who solved all financial puzzles) and Ebi.

Kjell and Kjellg must be acknowledged for the good moments, at atypical hours and days. Thanks to Mats, for bringing the freshness of the 70ís. A nonexhaustive list of amiable colleagues should include: Alice, Adam, Anita(s), Anne-Marie, Bastiaan, Carl-Wilhelm, Carolina, David, Elisabet, Erland, Eva, Eva-Lena, Giampiero, Håkan&Eka, Harald, Inger, Jesper, Jocke, Johan, Jonas, Kristin, Kåre, Kalle, Keyhan, Linda, Ludde, Magnus, Martin, Nikko, Nikolaj, Peter, PeRa, Philippe, Renat, Rolf, Sheri, Tan Lee, Tony, Tamas, Thomas, Tibor, Tina and Tobias. Special thanks to Lennart Nord; I very much enjoyed playing with and talking to him.

Among the musicians, I would like to thank Lars Fridén, Christer Johnsson, Knut Sönstevold, Bengt Rosengren, Ulf Bjurenhed, Dag Henriksson, Michael Schlyter, Dirk Schmidt, Gunilla Sundin, Martin Ericsson, Hans Samuelsson, Sven Larsson, Tore West and Inge Boström.

At the Karolinska Institute, I would like to thank Britta Hammarberg, Stellan Hertegård, Per-Åke Lindestad for the essential collaboration in the voice studies, and Miriam Katz-Salamon and Michael Runold for our helpful discussions on respiration, the availability the use of equipment, and for their friendship. I am also indebted to Curt von Euler.

Still in Sweden, a number of friends as well as their children deserve a big hug: Guilherme/Silvia, Peter/Marcia, Peter/Gunnel, Ubaldo/Gilda, Pär/Anne-Lee, Enrico/Claudia, Ary/Ma.Elisa, Heraldo/Annika, Adriana/Mauro, Monica/David, Grillo/Ki. Also, thanks to Azad, Bengt, Elvira, Ana Maria, Heiko, Sylvain, Vinicius, Bert, Azril, Tuire/Raymond, Steven, Thais, Marisa and Lydia, among others. Thanks, Wenner-Gren Center and Fredrik, for your warm hospitality.

No further away than a couple of keyboard commands, a phone call or a short letter, the friends were always available and on my mind: Ricardo (my "searcher"), João Afonso/Ana/Bruna, Adriano, Rodrigo/Elsebeth/Thiago, Pauxy/Piatã, Alexandre, Aribeth, Felipe, Admar, Luis Henrique, George, Alex Klein, Daniella, Jennifer, Alex Georg, Isnar/Simone/Pedro, Duda, Jocy, Fernando/Aude/Madalena/Matheus, Tadeu, Clóvis, Bill, Savio/Beth, Ayrosa/Isabel, Sérgio, Sonia, Rosi, Cearmando/Eliane, Bonturi, Firpo/Birgit/Fellippe/Helena, Cosme/Zênon, Roberto/Adri/Alan/Alexia, Luis Fernando and family, Domicio, Henrique/Sandra/kids, Tchê, Alex, Paulo/Ricardo, João, Samuca/Ligia, Laura/Eurico, Antonio, Daniel, Teca/Anna/Ilan, Rita/Cássio, Cibele, José Guilherme, Marcelo, Vera, Vereza, Zé Miguel, Patrick, Marcia/Dunga, to mention some.

I am also indebted to all my teachers, both in engineering (in particular to Ronaldo Soares de Andrade) and in music (in particular Wilson Dantas, Ricardo Rodrigues, Homero Magalhães, Luiza Quintanilha and Luis Carlos Justi).

These are only a few names, since I cannot adequately acknowledge all of the people to whom I am indebted. I hope the rest will know who they are and that I thank them very much.

Finally, I want to mention those who do not need to be mentioned, because they are the very reason for my existence, the family: my mother Rosa for her endless concern, love and support; Hilton, Bia, Julia and Diana; Adolfo, Chana, Monica and Dani; Marcos, Henrique, Raquel, Miguel, and their children, my cousins; Joanna; Antonio/Clea.


And vovó Branca, who always waited for us.