Evoked acoustic emissions from the human ear. V. Developmental changes.
Twenty young children, in whom evoked acoustic emissions were recorded at birth, were re-examined at the age of 4 years. None of the children showed evidence of sensorineural hearing impairment and it was possible to record a reproducible emission in all ears, which displayed normal otoscopy and tympanometry (n = 9). The new recordings were compared with those obtained at birth and the latency and the amplitude of the response both appeared unchanged. However, in some ears the frequency content of the dominant part of the emission was considerably lower at the age of four. The implication of this finding is briefly discussed in view of recent data on cochlear development, obtained from animal research.
Johnsen
N J
NJ
Department of Audiology, Gentofte University Hospital, Hellerup.
Parbo
J
J
Elberling
C
C
D002675:Child, Preschool; D003051:Cochlea / Q000502:physiology*; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D013016:Sound