Uncommon timing variation in the speech of an Icelandic-speaking child with protracted phonological development

The following paper presents an Icelandic-speaking child with protracted phonological development (PPD) over an intervention period (age 4;10 to 5;3) as a contribution to a special crosslinguistic issue describing individual profiles in PPD. Along with typical mismatch ("error") patterns, the child showed one pervasive and rare mismatch for Icelandic: compensatory lengthening of vowels when postvocalic consonant sequences reduced. Segment length is phonemic in Icelandic; thus, this pattern decreased her intelligibility considerably. A constraints-based nonlinear phonological framework served as a basis for analysis and intervention planning. Need addressed across the phonological hierarchy were: (1) accurate mapping between the timing tier (word structure level) and consonant and vowel tiers, through a focus on word-medial (WM) pre-aspirated stops; (2) onset complexity (word-initial (WI) /s/-clusters); and (3) a positional target, WI /f/. During intervention (17 sessions), she successfully produced training words for all targets. Monthly probes and a post-test at 5;3 revealed generalization to untrained words for pre-aspirated stops and labiodentals but not for /s/-clusters. Overall, compensatory vowel lengthening reduced substantially. The nonlinear analysis pointed specifically to the nature of the timing mismatches, supporting system-wide change.