Mothers' perceptions of infant distress vocalizations.

In the present study the psychological and acoustic properties of the distress vocalizations of five 3-4-month-old infants were examined. Each vocalization was rated on a 5-point scale from "definitely fuss" to "definitely cry" by mothers on two home visits. On the first home visit, each mother rated a set of her own infant's vocalizations recorded 1/2 hour previously and presented in the order of occurrence. Three weeks later, on the second home visit, mothers were presented with the master tape that contained the vocalizations of all five infants in random order. Analyses of the judgment data and acoustic parameters of the vocalizations revealed that (a) mothers were able to rate infant vocalizations reliably along a fuss-cry continuum, both shortly after these vocalizations were produced and 3 weeks later with fewer available nonacoustic, contextual cues; (b) mothers relied upon mean and peak intensity, mean F2 frequency, the ratio of F1 to F2, and mean duration in their judgments of infant cries versus fusses; and (c) although there was a high level of rating consistency across mothers, there were some discrepancies between visit 1 and 2 ratings due to the contribution of context cues present on visit 1 only.