14th International Congress of Phonetic Sciences (ICPhS-14)
San Francisco, CA, USA
A multiplanar Dynamic Magnetic Resonance Imaging (MRI) technique that extends our earlier work on single-plane Dynamic MRI is described. Scanned images acquired while an utterance is repeated are recombined to form pseudo-time-varying images of the vocal tract using a simultaneously recorded audio signal. There is no technical limit on the utterance length or number of slices that can be so imaged, though the number of repetitions required may be limited by the subject's stamina. An example of [pasi] imaged in three sagittal planes is shown; with a Signa GE 0.5 T MR scanner, 360 tokens were reconstructed to form a sequence of 39 3-slice 16 ms frames. From these, a 3-D volume was generated for each frame, and tract surfaces outlined manually. Parameters derived from these include: palate-tongue distances for [a,s,i]; estimates of tongue volume and of the area function using only the midsagittal, and then all three slices. These demonstrate the accuracy and usefulness of the technique.
Bibliographic reference. Shadle, Christine H. / Mohammad, Mohammad / Carter, John N. / Jackson, Phillip J. B. (1999): "Multi-planar dynamic magnetic resonance imaging: new tools for speech research.", In ICPhS-14, 623-626.