Poster D22, Friday, August 17, 4:45 – 6:30 pm, Room 2000AB
An EEG study on the influence of dialectal competence on neural processing of front vowels in German
German dialects sometimes differ from standard language in pronunciation. Swabian is such a dialect which is commonly spoken in the south-west of Germany. It shows a lowering of the high front vowel [ɪ] to [e] preceding a nasal and raising the low front vowel [ɛ] to [e] in closed syllables. Standard German, on the other hand does not have [e] in its phoneme inventory and uses it in unstressed syllables of loanwords only. Several studies of languages like American English, French or Swedish have shown that speakers of dialects with a merged vowel representation are less able to discriminate height contrasts in perception compared to speakers without merged vowels, hence, suggesting differences in vowel representation. This study investigates whether familiarity with the Swabian dialect affects the phonemic perception of front vowels by German native speakers. Event related potentials (ERPs) were measured in response to minimally differing German nouns (“Finger” [Standard German ‘finger’], “Fenger” [dialect variant ‘finger’ or ‘catcher’], “Fänger” [Standard German ‘catcher’]), containing the vowels [ɪ], [e] and [ɛ]. Two groups of subjects (n=26) with differing levels of dialect knowledge were recruited. Thirteen native speakers of German (6 females, 7 males; mean age=27,4) with perfect self-rated knowledge of their regional dialect were tested in the field with a mobile EEG system. Thirteen native speakers of Standard German (7 females, 6 males; mean age=25,2), grown up without any dialect, represented the comparison group which was tested in the laboratory. The stimuli were recorded from a dialect speaker. Each participant had to listen to three blocks of a multi-deviant passive oddball paradigm. Three alternating conditions of randomized stimuli were presented binaurally using OpenSesame via loudspeakers, while the participants were watching a silent film. The EEG was recorded using a 32-channel LiveAmp amplifier. Electrophysiological results show an overall mismatch negativity (MMN) in a typical time window from 150 to 300 ms post vowel onset between the overall standard and deviant condition (p=0.0007299). Dialect as well as standard speakers show the largest MMN amplitude for “Fänger” (vowel [ɛ]) irrespective of the direction of acoustic deviation. Both groups show reduced MMN amplitudes for “Fenger” (vowel [e]). However, for “Finger”, standard speakers show a larger MMN than dialect speakers. This finding supports the hypothesis that dialect speakers differ in their representation of the vowel [ɪ] in the context of a nasal consonant due to the attested lowering of high vowels in Swabian. In sum, we here show that dialect familiarity can shape the perception of acoustically similar vowels. This finding is particularly important because it shows different neurophysiological responses to the same acoustic stimuli in much the same way as has previously been shown between different languages.
Topic Area: Perception: Auditory