Tinnitus and inferior colliculus activity in chinchillas related to three distinct patterns of cochlear trauma.

A longstanding hypothesis is that tinnitus, the perception of sound without an external acoustic source, is triggered by a distinctive pattern of cochlear hair cell (HC) damage and that this subsequently leads to altered neural activity in the central auditory pathway. This hypothesis was tested by assessing behavioral evidence of tinnitus and spontaneous neural activity in the inferior colliculus (IC) after unilateral cochlear trauma. Chinchillas were assigned to four cochlear treatment groups.

Acoustic injury and TRPV1 expression in the cochlear spiral ganglion.

Acoustic trauma not only produces temporary and permanent hearing loss but is a common cause of chronic tinnitus. Recent work indicated a possible role for the transient receptor potential channel vanilloid subfamily type 1 (TRPV1) in modulating the effects of cochlear injury. In our research, we investigated the effects of acoustic damage on TRPV1 expression in spiral ganglion neurons of adult rats.