Development of the vocal fundamental frequency of spontaneous cries during the first 3 months

Studies in the field of cry diagnosis have concentrated on the fundamental frequency (F(0)) and related parameters as suitable predictors for an at-risk status of the infant for a CNS dysfunction, mostly reflected in an increased F(0). The high variability of F(0) in infant cries is a limiting factor to develop cry analysis as a non-invasive tool for early diagnosis. As only a few longitudinal studies were carried out, our case study wants to contribute to provide developmental data on fundamental frequency of infant cries with a considerable higher time resolution (shorter recording interval). The fundamental frequency of spontaneous cries of one male infant was analyzed using KAY-CSL 4300 for its daily characteristics during the first 3 months of life. This dense sampling interval (daily recordings) enabled the description of the range of temporary changes of the fundamental frequency during the observation period. The mean fundamental frequency values of cries uttered at single days and of the cries of successive days were relatively variable. In contrast to former studies, no significant decreasing or increasing trend of the mean fundamental frequency of all analyzed cries was found through the first 3 months of life. Only cries shorter than 0.8 s showed an increasing developmental trend of the mean F(0).