AUDITORY EVOKED POTENTIAL P300 IN TINNITUS PATIENTS WITH NORMAL HEARING

Abstract

Background: Tinnitus is defined as the perception of sound in the absence of acoustic events. This sound perception or noise emanating from the ears or head ranges from a barely noticeable annoyance to a debilitating chronic condition. Objective: To assess the P300 response in subjects with tinnitus and normal hearing and compare that response with normal hearing subjects without tinnitus. Patients and Methods: In this study we assessed P300 in 20 normal hearing subjects and compared their results with the results of P300 in 20 tinnitus subject with normal hearing. All study subjects underwent full history taking, otological examination, basic audio logical evaluation, otoacoustic emission and electrophysiological test (P300). No significant difference was found between both groups as regard hearing threshold, speech audiometry, immittancemetry and otoacoustic emission. Results: Tinnitus patients had longer P300 latencies than normal subjects which was not significant, and lower P300 amplitude which was significant. These results reflected that tinnitus patients have poor attention ability as the components of long latency auditory evoked potential were influenced by the degree of attention to the stimulus, involvement of the central auditory nervous system, suggesting a participation of the auditory cortex in the generation, and/or tinnitus maintenance. Conclusion: P300 test may be a useful tool for objective assessment of tinnitus patient and to evaluate the neurocognitive status of tinnitus patient.