Which of the following condition is associated with a loss of attenuation reflex?
In stapedial palsy, damage to the nerve result in a reduction in sound attenuation reflex resulting in sound being heard excessively loud in the affected ear (hyperacusis). Attenuation reflex: When very loud sound is transmitted through the ossicular system to CNS a reflex is initiated with a latent period of 40 to 80ms. This reflex causes contraction of tensor tympani and stapedius muscle. Contraction of these two muscles make the ossicular system rigid and therefore it fails to vibrate with the sound wave. Thus sound is not allowed to enter inner ear or its intensity is reduced by 30 to 40 decibels.
Stapedial palsy
Glomus tumor
Internal ear pathology
Malingerers