Abstract
Distortion product otoacoustic emissions (DP-OAE) (2×f1-f2) were measured in guinea pigs with approximatemly 4kHz primary tones (f1=3.9875kHz, f2/f2=1.225). DP-OAE was measured in all normal subjects. They completely disappeared after asphyxia for two minutes.
The effects of intravenous injection of lidocaine on DP-OAE were examined. DP-OAE was increased after lidocaine injection for about 15 minutes, and returned to the normal state. This increase suggested direct or indirect effect of lidocaine to the cochlea, and possible relation of cochlear efferent pathways.
