Enriched acoustic environment after noise trauma abolishes neural signs of tinnitus.
Noise-induced hearing loss induces reorganization of the tonotopic map in cat auditory cortex and increases spontaneous firing rate and neural synchrony. We showed previously that keeping cats after noise trauma in an acoustic environment enriched in high frequencies prevents tonotopic map reorganization. Here, we show the effects of low-frequency and high-frequency enriched acoustic environments on spontaneous firing rate and neural synchrony. Exposed cats placed in the quiet environment and in the low-frequency enriched acoustic environment showed increased spontaneous firing rate and synchrony of firing. In contrast, exposed cats placed in the high-frequency enriched acoustic environment did not show significant differences in spontaneous firing rate or synchrony compared with normal hearing controls. This is interpreted as an absence of putative neural signs of tinnitus.
Noreña
Arnaud J
AJ
Neurosciences and Sensory Systems Laboratory, UMR CNRS 5020, Université Claude Bernard, Lyon, France.
Eggermont
Jos J
JJ
D000161:Acoustic Stimulation / Q000379:methods*; D000200:Action Potentials / Q000502:physiology / Q000528:radiation effects; D000818:Animals; D001309:Auditory Threshold / Q000528:radiation effects; D001931:Brain Mapping; D002415:Cats; D004307:Dose-Response Relationship, Radiation; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology / Q000528:radiation effects; D006317:Hearing Loss, Noise-Induced / Q000150:complications / Q000503:physiopathology*; D009474:Neurons / Q000502:physiology / Q000528:radiation effects; D014012:Tinnitus / Q000209:etiology / Q000517:prevention & control*