December 2010

Document Type


Degree Name



Dept. of Biomedical Engineering


Oregon Health & Science University


A number of studies have shown that the intelligibility of speech spoken deliberately clearly, referred to as “clear speech” or CLR speech, is higher than that of speech spoken during typical communication, referred to as “conversational speech” or CNV speech. Significant changes in the acoustic features of CLR speech, as compared to those of CNV speech, have been found in previous studies. However, little is known about the relationship between speech intelligibility and the individual sets of acoustic features that are typical in CLR speech. Our long-term goal is to better understand and model those features that contribute to speech intelligibility for different groups of normal-hearing listeners. One objective of this thesis is to identify acoustic features that contribute to the increased intelligibility of CLR speech over CNV speech, which we refer to as “relevant features” for normal-hearing listeners. Our hypothesis is that some acoustic features are more relevant to increased




School of Medicine



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.