Cumulative syllable-scale power spectra

Babies start making speech-like vocalizations long before they start to produce recognizable words — various stages of these sounds are variously described as cries, grunts, coos, goos, yells, growls, squeals, and "reduplicated" or "variegated" babbling. Developmental progress is marked by variable mixtures of variable versions of these noises, and their analysis may provide early evidence […]