Articulation Rate Between 2 and 4 Years of Age in French Children's Spontaneous Speech.

Aim: This study reports age-related changes in articulation rate (syllables [SPS] and phones per second [PPS]) during spontaneous speech in French children aged 2-4 years and provides baseline values for this age range.

Method: In this cross-sectional study, spontaneous speech (4,361 utterances) from 91 French children was collected. The articulation rate was calculated in SPS and PPS and was observed as a function of seven age groups. The distribution of articulation rate values for utterances in SPS and PPS by percentiles is provided.

Results: In line with previous studies, the results confirm that the articulation rate increased with age. It increased from 3.14 to 3.88 SPS between 22 and 50 months, and from 6.06 to 8.31 PPS with significant changes emerging at 38-41 months. The results also indicate that the number of sounds per syllable increased significantly with age and that the growth in syllable structure complexity preceded that of articulation rate in SPS.

Conclusions: This study adds to the already available benchmarks for articulation rate by providing new data for French preschoolers. Further studies are still needed to understand what other factors (e.g., cognitive, linguistic and spontaneous speech styles) may be involved in the growth of articulation rate during development.