Association between Tinnitus and Auditory Middle Latency Response: An Exploratory Study

Tinnitus is a concerning condition that affects most adults worldwide, with a prevalence of 6.7%. Theories of tinnitus have explained that an increase in spontaneous neural activity at the level of the thalamus could induce tinnitus. There are no standardized objective tests for tinnitus assessment because of its multifaceted nature. Hence, the current study aimed to explore the effect of Tinnitus on Latency and Amplitude of the Auditory Middle Latency Response in Audiological Attendees. The study recruited 50 individuals (25 normals and 25 individuals with tinnitus) who underwent audiological evaluations like Pure tone audiometry, immittance, pitch and loudness matching, THI and middle latency response. The IHS program was used to record MLR, which was obtained using tone burst stimuli of 500 Hz, 1 KHz, 2 KHz, and 4 KHz at a rate of 7.1/s with a constant duration of 5 ms, for a total of 1500 sweeps. As a covariate, pure tone thresholds were one of the variabilities that were addressed by ANCOVA. The amplitude of the Pa component varied significantly between the tinnitus and control groups, according to the MLR data and no other components of MLR reached that significance. Furthermore, there was no discernible variation in the latency or amplitude of MLR among any of the other components. The latency of the waveforms increased as the stimulus frequency increased. Karl Pearson correlation coefficient showed no significant correlation between THI scores and any of the outcome measures except for Pa amplitude. As the Pa component of MLR showed maximum changes between controls and individuals with tinnitus, the Pa component could be considered a potential tool for identifying neurophysiological changes related to tinnitus.