ABSTRACT
Objective To observe effect of olivo-cochlear feedback produced by a contralateral noise on the inhibition of electrophysiological cochleaoneural activity under sedation and anesthesia with or without maintenance of temperature to investigate the effect of sedation and anesthesia on the cochlear efferent system function. Methods The recording of electrophysiological cochleoneural activity was to implant an electrode at the round window, the ASECA (average spectrum of electrophysiological cochleaoneural activity) was obtained to FFT transform for the signal recorded. Results The results indicated that the effects of contralateral noise on ASECA were notably diminished during sedation and were almost completely suppressed during anesthesia either with or without maintenance temperature. Conclusion The present study shows that sedation and anesthesia respectively diminish and suppresse the cochlear efferent system functions.