| |
Abstract:
Five Swedish fricatives have been analysed in different vowel
contexts using Magnetic Resonance Imaging (MRI). The fricatives
were acquired for sustained articulations in four VCV contexts in
the midsagittal plane and in three vowel contexts in full 3D for
one male native speaker of Swedish. The VCV context was created
by having the subject make the initial VC transition before the
acquisition, then holding the fricative articulation while
breathing out very slowly and finally making the CV transition
after the scan. The MR images in the 3D set were used for
three-dimensional reconstructions of the vocal tract shape from
which the area function could be calculated. The vocal tract
outline in the midsagittal plane was extracted from the
midsagittal images and a number of articulatory measures were
determined from this contour. Coarticulation was studied based on
the area functions, midsagittal vocal tract outline and the
articulatory measures. Coarticulatory effects was found for the
place and size of constriction, the protrusion, the jaw and
larynx height and the cross-sectional area. Synergetic coupling
were also found between the jaw advancing and lip protrusion and
between the larynx height and lip protrusion. The results of the
study will be incorporated in the KTH 3D vocal tract model to
account for coarticulation. Examples of midsagittal and
three-dimensional MR images, as well as reconstructed vocal tract
shapes can be found from the KTH 3D Vocal Tract Project page at
http://www.speech.kth.se/multimodal/vocaltract.html
|
