Figure 1.

Salicylate dose dependently induces tinnitus-like behavior. Schedule-induced polydipsia avoidance conditioning (SIP-AC) was used to determine the dose of sodium salicylate that could induce tinnitus. Rats were trained to avoid foot shocks on trials in which sound was presented and only lick on trials with no sound (quiet). Here is a schematic illustrating lick suppression data obtained with SIP-AC as a function of salicylate dose. Rats seldom licked on trials when a sound was presented regardless of the salicylate dose or in the absence of salicylate (0 = control). On no-sound trials, rats licked robustly in the absence of salicylate (0 mg/kg, control); however, as the dose of salicylate exceeded 100 mg/kg, licks on no-sound trials largely ceased, which is behavioral evidence that the rats were perceiving the phantom sound of tinnitus in the absence of an external stimulus.