The Acoustic Middle Ear Reflex In Unanesthetized Rabbits

Abstract

It is demonstrated that the response of the acoustic middle ear reflex can be recorded in awake rabbits by measuring the change in the acoustic impedance in a way similar to what has been done in man. The excitability of the reflex was measured in the frequency range between 500 and 3000 cps. The reproducibility of the measurement in the same rabbit is in the order of 3 dB over a period of one month, whereas there is a considerable individual variation. It was found that the excitability of the reflex is slightly higher when activated by ipsilateral than by contralateral stimulation. It was further shown that the reflex exhibits no appreciable fatigue during a 1 minute stimulation with a 2000 cps pure tone.