The effect of sentence accent, word stress, and word class (function words vs. content words) on the pronunciation of Dutch vowels was investigated. It was found that these linguistic factors have a clear influence both on the duration and on the position of ('steady-state') formant frequencies of vowels. Furthermore it was found that the shift of formant frequencies due to these factors is not necessarily towards the centre of the vowel triangle because of an interaction between spectral reduction and coarticulation.
Bibliographic reference. Bergem, Dick R. van (1991): "The influence of sentence accent, word stress, and word class on the quality of vowels", In EUROSPEECH-1991, 1455-1458.