First and second formant histories have been used in studies of both normal and disordered
speech to indirectly measure the activity of the vocal tract. The purpose of the present study
was to determine the extent to which formant measures are reflective of lingual movements
during diphthong production. Twenty native speakers of American English from the western
United States produced four diphthongs in a sentence context while tongue movement was
measured with a magnetic tracking system. Correlations were computed between the …