Acoustic correlates of inspiratory phonation during infant cry.

The duration and vocal fundamental frequency (Fo) of inspiratory cries produced by a group of 20 healthy infants were measured. Similar acoustic measures were applied to the cries immediately preceding and following an inspiratory cry as a means of characterizing an inspiratory "event." Results were that the number of inspiratory cries varied considerably from child to child during a complete crying episode. The duration and Fo of inspiratory cries were significantly shorter and higher, respectively, in comparison to cries immediately preceding and following the inspiratory cry. In addition, the gap duration following an inspiratory cry was significantly greater than the pre-inspiratory gap duration. Discussion centers on the anatomical and physiological bases of inspiratory cry phonation. Implications as well as the need to consider the inspiratory portion of crying behavior when examining infants at risk for respiratory distress also are discussed.