Navajo Ultrasound data
These recordings were made in 2003, at Haskins Laboratories, of native Navajo speaker Elise Whitehead. Ms. Whitehead read from a wordlist emphasizing sh and s, laterals, and prefix-noun utterances. An audio recording was made, accompanied by ultrasound imaging, using the Haskins Optically Corrected Ultrasound System, or HOCUS (Whalen et al., 2005). This system allows them to relate the ultrasound's picture of the tongue surface to the rest of the vocal tract (the palate and rear pharyngeal wall) by compensating for movement of both the head and the ultrasound transceiver. In this way, they get a good look at what is going on throughout the vocal tract, including the upper pharynx, which is typically hard to image. Later the ultrasound was transferred to AVI archival video format. JD Ross Leahy used Transcriber and ELAN to time-align audio and video files with transcriptions contributed by Joyce McDonough. The silent movie file, the audio file, and the EAF (Eudico Annotation Format) file were then contributed by ELF president Douglas H. Whalen to the E-MELD project. A complete description of the recording and transcription methods can be found at the E-MELD website.
These recordings are intended to illustrate the possibilities in using ultrasound data for linguistic analysis. Ultrasound is useful in phonetic fieldwork because it enables a linguist to record accurate images of dynamic tongue shape during speech. By analyzing these images, a linguist can study the actions of the tongue root and sagittal groove, the interaction between vowels and lingual consonants, timing of articulatory events and overall tongue shape.