... nasal vowels . Second , if shifts in the low - frequency center of gravity due to nasal coupling influence perceived vowel quality , then phonological vowel systems should exhibit consistent differences in the height , backness , and ... Although nasalization has been discussed in the context of more general aspects of linguistics in other books, this text is the first and primary resource focusing solely on nasalization. This volume features articles discussing all aspects of nasalization, including physiology, perception, aerodynamics, acoustics, phonetic and phonological representations, research methodology, and instrumentation. Each chapter examines important research advances achieved within the last ten years and closes with a detailed discussion of the current research.