On the Role of Temporal Variability in the Acquisition of the German Vowel Length Contrast

This study is part of a larger project investigating the acquisition of stable vowel-plus-consonant timing patterns needed to convey the phonemic vowel length and the voicing contrast in German. The research is motivated by findings showing greater temporal variability in children until the age of 12. The specific aims of the current study were to test (1) whether temporal variability in the production of the vowel length contrast decreases with increasing age (in general and more so when the variability is speech rate induced) and (2) whether duration cues are perceived more categorically with increasing age. Production and perception data were obtained from eleven preschool, five school children and eleven adults. Results revealed that children produce the quantity contrast with temporal patterns that are similar to adults’ patterns, although vowel duration was overall longer and variability slightly higher in faster speech and younger children. Apart from that, the two groups of children did not differ in production. In perception, however, school children’s response patterns to a continuum from a long vowel to a short vowel word were in between those of adults and preschool children. Findings are discussed with respect to motor control and phonemic abstraction.