An experimental study of vowel duration in Iraqi spoken Arabic
This is an experimental study of vowel duration in I.S.A. (Iraqi Spoken Arabic). It investigates some myodynamic (articulatory), aerodynamic, acoustic and perceptual correlates of vowel duration and aims at answering, partly at least, the question whether the factors governing the systematic variations of vowel duration are phonetic-universal or language-specific phenomena. It falls into two main parts: PART ONE comprises three chapters. Chapter One gives a general phonological background of I.S.A. with special reference to the phonemic significance of vowel length and its correlation with stress. Chapter Two reviews some of the literature on vowel duration. The literature review is confined to a critical survey of particular aspects of vowel duration viz; intrinsic duration of vowels, segmental conditioning of vowel duration i.e. the influence of voicing and manner of articulation of the preceding and following consonants and the place of articulation of the following consonants on vowel duration, the influence of stress and gemination on vowel duration and some of the literature on the perception of duration. Chapter Three reviews critically some of the hypotheses for the interpretation of vowel duration in myodynamic (articulatory) and aerodynamic terms. The hypotheses reviewed are articulatory distance, force of articulation and articulatory energy expenditure, contrasting aerodynamic conditions, laryngeal adjustment, temporal compensation and closure transition. PART TWO comprises three chapters giving details of the experimental investigation and discussion of results. The intention has been to keep in line with the same aspects of vowel duration reviewed in Part One; the same aspects have been investigated from the acoustic point of view in Chapter Four. The acoustic findings have been subjected to a myodynamic and aerodynamic investigation in Chapter Five. The results of both chapters have been subjected to statistical treatment. In Chapter Six the findings of both Chapter Four and Five are summarized and discussed from the myodynamic, aerodynamic, acoustic and perceptual points of view. Suggestions for further research have also been included at the end of this chapter.