The intermediate degree of VOT in Japanese initial voiceless stops

Previous studies of aspiration and VOT in Japanese have led to /p/, /t/, and /k/ being inconsistently described as either unaspirated or moderately aspirated. The purpose of this paper is to resolve this issue. Assessing the productions of 13 monolingual Japanese talkers living in Japan, we repeated part of a VOT study that was based on 6 Japanese bilinguals living in the UK. For each talker we assessed the VOT in 44 voiceless stops, including 12 for /p/, 12 for /t/, and 20 for /k/. We found that Japanese VOT for /p/, /t/, and /k/ was 30.0, 28.5, and 56.7 ms, respectively, and longer than the VOT of two short lag comparison groups and shorter than the VOT of two long lag comparison groups. We conclude that Japanese voiceless stops have an intermediate degree of aspiration and constitute an exception to the short lag and long lag dichotomy of voiceless stops said to characterize many languages.