LINGUIST List 15.449

Tue Feb 3 2004

Diss: Phonetics: Bonaventura: 'Invariant...'

Editor for this issue: Takako Matsui <takolinguistlist.org>

Directory

1. bonaventura.8, Invariant patterns in articulatory movements

Institution: Ohio State University
Program: Department of Speech and Hearing
Dissertation Status: Completed
Degree Date: 2003

Author: Patrizia Bonaventura

Dissertation Title: Invariant patterns in articulatory movements

Dissertation URL: http://www.ohiolink.edu/etd/view.cgi?osu1070119339

Linguistic Field: Phonetics, Phonology, Cognitive Science
 
Dissertation Director 1: Osamu Fujimura
Dissertation Director 2: Michael Trudeau
Dissertation Director 3: DeLiang Wang
Dissertation Director 4: Wayne King

Dissertation Abstract:

The purpose of the study is to discover an effective method of
characterizing movement patterns of the crucial articulator as the
function of an abstract syllable magnitude and the adjacent
boundary, and at the same time to investigate effects of prosodic
control on utterance organization.

In particular, the speed of movement when a flesh-point on the tongue
blade or the lower lip crosses a selected position relative to the
occlusion plane is examined. The time of such crossing provides an
effective measure of syllable timing and syllable duration according
to previous work. In the present work, using a very limited vocabulary
with only a few consonants and one vowel as the key speech materials,
effects of contrastive emphasis on demisyllabic movement patterns were
studied. The theoretical framework for this analysis is the C/D model
of speech production in relation to the concept of an invariant part
of selected articulatory movements.

The results show evidence in favor of the existence of 'iceberg'
patterns, but a linear dependence of slope on the total excursion of
the demisyllabic movement, instead of the approximate constancy of the
threshold crossing speed as suggested in the original proposal of the
'iceberg', has been found. Accordingly, a revision of the original
concept of 'iceberg' seems necessary. This refinement is consistent
with the C/D model assumption on 'prominence control' that the
syllable magnitude determines the movement amplitude, accompanying
directly related syllable duration change. In this assumption, the
movement of a consonantal component should also be proportional to
syllable magnitude. The results suggest, however, systematic outliers
deviating from the linear dependence of movement speed on
excursion. This deviation may be caused by the effect of the
immediately following boundary, often referred to as phrase-final
elongation.