Contextual effects on the distinction of Japanese length contrasts in reverberation

• Published in: The Journal of the Acoustical Society of America 2019-10, Vol.146 (4), p.3054-3054
• Main Authors: Osawa, Eri, Arai, Takayuki
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.5137594

Temporal structure in a word is crucial for understanding speech. In the distinction between Japanese singleton and geminate stops, listeners tended to perceive a consonant as geminate when the preceding vowel was longer [Ofuka et al., J. Phonetics Soc. Japan 9(2), 59–65 (2005)]. At the same time, listeners may not be able to use the contextual information in reverberation since the boundaries between each speech sound may become blurred by reverberation elongating and overlapping the sounds. The current study investigated whether the category boundary between singleton and geminate might change depending on duration of the preceding vowel in reverberation. Participants made a choice between singleton and geminate consonants embedded in an /a a/ context. The duration of the preceding vowel was changed. The experiments were conducted in a reverberant (RT = 2.6 s) and non-reverberant (RT = 0.1 s) condition. The results showed a significant shift in category boundary which indicated that listeners gave more “geminate” responses when the preceding vowel was longer, especially in the reverberant condition. The preceding vowel lengthened by reverberation caused listeners to choose “geminate.” Listeners might be more sensitive to the length of the adjacent phonemes for assessing the degree of reverberation.