TOWARDS UNDERSTANDING THE PROTRACTED ACQUISITION OF ENGLISH RHYTHM.

Several global and specific rhythm metrics and speech rate were used to characterize differences in the rhythms of 5- and 8-year-olds' spoken English. The results were that only speech rate and the rate-normalized Pairwise Variability Index (nPVI) differentiated between 5- and 8-year-olds' speech. A further result was that the variance in nPVI values was better explained by a specific measure devised to capture patterns of supralexical accenting than by the factor of age expressed in months. These results are taken to suggest that the protracted acquisition of English rhythm may be due in part to the slow rate at which children acquire prosodically conditioned vowel reduction.