Correlation between amplitude and frequency fluctuations of spontaneous otoacoustic emissions.
The normalized cross-correlation function between the amplitude and frequency fluctuations of 11 spontaneous otoacoustic emissions was measured. A significant correlation was found in seven subjects. The correlation coefficient ranged from -0.37 to +0.65 across subjects. In four subjects, the amplitude fluctuation lagged the frequency fluctuation. The time lag was between 1.6 and 5.5 ms. The results were interpreted using a noise-perturbed limit-cycle oscillator with nonlinear (Duffing) stiffness as a model for a spontaneous emission. The data show that the relative increase of the nonlinear stiffness in this model was between -0.010 and +0.015. This indicates that an even-order nonlinear stiffness plays a minor role in the emission generator.
van Dijk
P
P
Institute of Audiology, University Hospital, Groningen, The Netherlands.
Wit
H P
HP
Tubis
A
A
Talmadge
C L
CL
Long
G R
GR
D000161:Acoustic Stimulation; D003051:Cochlea; D006801:Humans; D008962:Models, Theoretical; D009622:Noise; D017084:Otoacoustic Emissions, Spontaneous; D013997:Time Factors