Time-frequency analysis of neonatal click-evoked otoacoustic emissions.
Click-evoked otoacoustic emissions (CEOAEs) of full-term babies were considered. By means of the wavelet transform, each CEOAE was decomposed into frequency bands. The rms amplitude and test-retest correlation were computed from these bands. The results indicated that both the amplitude and correlation were not invariant with time but reached a maximum in specific time windows, depending on the frequency of the component. For all components, the correlation was greatly decreased for latencies > 12.5 ms. As a result, comparison between the performance of the default ILO 88 window (2.5-20 ms) and the 2.5-12.5 ms window showed that for all frequencies in the 1.5-6 kHz range there was a statistically significant improvement in the correlation.
Tognola
G
G
CNR Centre of Biomedical Engineering, Polytechnic of Milan, Italy. tognola@biomed.polimi.it
Grandori
F
F
Ravazzani
P
P
D005163:Factor Analysis, Statistical; D006311:Hearing Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D007231:Infant, Newborn; D015997:Neonatal Screening; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D013997:Time Factors