Magnetic Resonance Imaging of the moving vocal tract
In the last decade or so, there has been a number of pioneering studies of vocal tract shapes, using Magnetic Resonance Imaging. Since the "exposure time" required in these early studies was rather long (many seconds), only prolongable articulations - vowels and continuant consonants (e.g. nasals, liquids and fricatives) - could be examined.
More recently, a number of research groups have attempted to acquire dynamic MRI image sequences, i.e. MRI "movies". One very successful technique involves the acquisition of single images from an utterance that is repeated over and over again. The single images, from different times in the production of the utterance, can be put together to form an animation, showing the movements of speech organs with a very fine degree of temporal resolution.
Click on the images below to see our latest movies. Graduate student Zeynab Raeesy has recently added sound to them recorded at the time they were made. The audio quality is rather "tinny" because of the noise-reduction techniques that have been applied to overcome the very loud sound of the MRI scanner. (Resize the movie window so it is about the size of these pictures, otherwise the video will appear rather pixellated.)
"Answered a door". | "Dancer four" | "Sauce saucer" |
Further information with other examples of our earlier research on dynamic MRI is available here. The original proposal and the final report are available here.
Phonetics Lab MRI movie @Bristol science centre
One of our vocal tract movies, "undid a door", has been used in an exhibit about speech in a new exhibit created by the @Bristol science centre, part of their interactive exhibition about the human body, "All About Us".
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(Click on the photo to watch the movie play. NB: the movie is silent, so don't adjust your volume control!) |
John Coleman (left) and Greg Kochanski (right) demonstrate the speech exbibit to @Bristol science centre visitors at the launch event in March 2011. |