Loss of prevoicing in modern Japanese /g, d, b/

In several dialects of Japanese, including the Tokyoarea dialects that are the basis for the standard variety, there is an apparent change in progress that affects the pronunciation of word-initial /g, d, b/. Although young speakers today often produce these stops with short-lag voice onset time (VOT), the distribution of VOT values measured in productions by several generations of speakers in a database that was recorded ten years ago suggests a phonetically gradual shift from very heavily voiced variants (with extra-long lead VOT) to less heavily voiced variants, rather than a phonologically gradual diffusion of a discrete change to “devoiced” values. The extremely long VOT values in the productions of the oldest speakers in the database are in keeping with philological evidence suggesting that the starting point for the change was a series of prenasalized stops. The suggestion is evaluated against the crossgenerational corpus using two phonetic measures that might index the degree of nasal venting of oral air pressure during the closure of a pre-voiced stop.