AIMTo create a simple behavioral procedure for detecting tinnitus of rats.

METHODSA procedure based on a Pavlovian-conditioned suppression paradigm was set referencing Jastreboff's way to detect tinnitus behaviorally in conscious animals. Rats received acquisition training through Pavlovian conditioning to associate the conditioned stimulus (noise offset) with the unavoidable unconditioned stimulus (foot-shock). The manifestation here is escape reaction. An extinction procedure followed, during which the subject was exposed to the conditioned stimulus, but shock is no longer given. The manifestations of the rats in different group during the extinction processes were observed. Tinnitus was induced by salicylate (SA) injection to validate the method.

RESULTSThe escaped rate of SA group is lower than that of the control. It indicated that the SA rats escaped seldom when there was a sound off, because the rats might perceive the salicylate-induced auditory sensation as a substitute for the background noise that had acquired a safety value during training.

CONCLUSIONThe behavioral procedure could be used to detect tinnitus of rats induced by salicylate.