Articulatory Evidence for the Syllable-final Nasal Merging in Taiwan Mandarin

Area of Science:

• Linguistics
• Phonetics
• Acoustic Phonetics

Background:

• Syllable-final nasals /n/ and /ŋ/ in Taiwan Mandarin are reportedly merging.
• Previous perceptual studies suggest this merging is context-sensitive and vowel-dependent, often attributed to social factors.

Purpose of the Study:

• To investigate the articulatory mechanisms underlying the merging of syllable-final nasals in Taiwan Mandarin.
• To determine whether biomechanical constraints or socio-dialectal factors are primary drivers of this phonological change.

Main Methods:

• Utilized ultrasonography to capture dynamic tongue postures during the production of syllable-final nasals.
• Employed computational 3D tongue models to simulate articulatory biomechanics.
• Correlated articulatory data with perceptual findings on nasal merging.

Main Results:

• Confirmed that the merging of syllable-final nasals is vowel-dependent, aligning with prior perceptual studies.
• Ultrasonography and biomechanical simulations indicate that tongue posture and biomechanics are key factors in the observed merging.
• Some speakers exhibit contrastive nasalization despite merged tongue postures, suggesting an incomplete merger.

Conclusions:

• The merging of syllable-final nasals in Taiwan Mandarin is significantly influenced by the biomechanics of the tongue.
• Articulatory constraints provide a more robust explanation for vowel-dependent merging patterns than previously proposed socio-dialectal factors.
• The ongoing merger may be incomplete, with residual phonetic cues (nasalization) maintained by some speakers.