FORMANT FREQUENCY DEVELOPMENT - 15 TO 36 MONTHS

Developmental characteristics of formant 1 (F1) and formant 2 (F2) are reported for spontaneous vocalizations produced by four young childre n, Each child was systematically sampled at between 15 and 36 months o f age. Results indicated that both FI and F2 remained relatively uncha nged prior to 24 months of age. Significant decreases in average F1 an d F2 occurred between 24 and 36 months. When Fl and F2 values were cat egorized according to tongue elevation and tongue advancement, the mos t significant changes were associated with high/back articulations. Th e pattern of formant frequencies noted in the present group of childre n appears to reflect developmental changes in vocal tract growth and r econfiguration.