VOWELS IN STANDARD AUSTRIAN GERMAN - Acoustics ...

Sylvia Moosmüller
both symmetrical and non-symmetrical vowel contexts were first documented by Houde
(1967, cited in Lindblom et al. 2002). Troughs in non-symmetrical V1pV2 sequences
were also found in Alfonso & Baer (1982).
Usually, troughs are investigated in symmetrical vowel contexts. Contrary to the
assumption that, during a bilabial closure, the tongue maintains its position in
symmetrical vowel contexts, a momentary deactivation of the tongue musculature
responsible for the vowel can be observed. Fuchs et al. (2004) could show that troughs
are the result of both aerodynamic forces (largest genioglossus posterior deactivation for
/p/, smallest for /m/, intermediate for /b/) and a recombination of jaw and tongue
movements. The deactivation of genioglossus posterior starts at the beginning of the
closure. However, tongue deactivation can also be suppressed; McAllister & Engstrand
(1991), could prove language-specific differences:
“In particular, the English and Swedish data both display a deep “trough” in the electrode
activation pattern, corresponding to a relaxation of the tongue position roughly coinciding
with the consonant; the tendency to such a trough in the French pattern is too weak to be
statistically significant.” (McAllister & Engstrand 1991: 9).
For Italian, Farnetani (1991) could show that troughs are minimal when consonants are
flanked by /i/, whereas in /a/ contexts, substantial peaks occur during the consonant.
The /ipi/ pattern represented in Farnetani (1991) resemble the /ipi/ patterns for French
shown in McAllister & Engstrand (1991). These language-specific differences in tongue
displacement during a bilabial closure in both symmetrical and non-symmetrical vowel
contexts again point out that, where the trough is missing, a process is at work which
assimilates the target tongue position of the bilabial plosive to the tongue positions of
the flanking vowels (e.g. in French and Italian). Missing troughs, analyzed as phonetic
processes, are no counterargument to Lindblom et al.’s (2002) conclusion that the
trough effect, in case it is a consistent phonetic phenomenon, gives evidence for a
phoneme-by-phoneme execution of articulatory gestures.
138