Thesis (B.Sc)--University of Hong Kong, 2008.Also available in print.Includes bibliographical references (leaves 27-30).A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, June 30, 2008.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science