Stimulus-frequency otoacoustic emissions in human newborns.

This study presents the first reported measurements of stimulus frequency emissions (SFOAEs) in 15 human newborns and compares their magnitudes and phase-gradient delays to those reported in adults. SFOAEs in newborns were measured at stimulus levels as low as 15 dB sound pressure level (SPL). Responses were compared between adults and newborns at stimulus levels where SFOAEs in both age groups demonstrated approximately linear growth (<40 dB SPL for newborns, <25 dB SPL for adults). Neonates had adult-like SFOAE delays when compared in this fashion, which compensates for newborn middle ear inefficiencies.