The Use of Masking in Evoked Response Audiometry

Abstract

The authors studied the influence of white noise on acoustically evoked potetials. In evoked reponse audiometry (ERA), the rules of masking in common use in subjective audiometry must be applied. Bone conduction caused an evoked potential from the opposite ear even for 0-5 dB. To avoid cross-hearing, masking of the opposite ear is required. A noise level below 50 dB had only little effect on the evoked potentials of the contralateral ear

For contralateral noise levels exceeding 60 dB or monaural stimulation with white noise and tones, the threshold was displaced by the amount of the masking noise level, and the steepness of the input-output curve was increased. In 16 patients with inner ear deafness, this masking effect showed a different behaviour. Thus an additional diagnosis on inner ear deafness is possible in ERA

Key Words:

• Electric response audiometry
• Evoked response audiometry (ERA)
• Auditory masking
• Cross-hearing
• Masking in ERA
• Sensorineural hearing loss