Interspeaker variation as the long term outcome of dialectally varied input: speech production evidence for fine-grained plasticity

The English stop voicing contrast is examined in both wordinitial position (via VOT) and word-final position (via the duration of the preceding vowel) in young adult speakers born and brought up in the Shetland Isles. The subjects’ parents were either also from Shetland, from elsewhere in Scotland, or England. All have identical phonemic stop systems, unambiguously so in initial position. The quasi-phonemic role in Scottish English of vowel duration in signaling the suffixual vs. tautomorphemic word final /d/ instead of the /t/-/d/ contrast (the Scottish Vowel Length Rule) renders final position more complex. There are fine-grained interspeaker differences covering a wide area of the phonetic space, exemplifying the potential for phonologically-relevant variation. The targets may be speaker-specific responses to input, especially mismatches between the dialect of their parents and the wider community.