Auditory reaction times in patients with chronic tinnitus with normal hearing

Hypothesis: This study aimed to compare reaction times (RTs) to auditory st imuli of two groups of normal-hearing subjects differing only in terms of t innitus sensation. Background: The RTs to auditory stimuli as a psychophysical measurement for threshold and suprathreshold hearing are said to provide a behavioral clue to some aspects of neural processing in the auditory system. Methods: To explore how patients with tinnitus perceive the intensity of th reshold and suprathreshold sound stimuli, RTs were obtained from normal-hea ring subjects with tinnitus (experimental group, N = 15) and from normal-he aring subjects without tinnitus (control group, N = 15) by means of exposur e to two different sets of frequencies: the tinnitus frequencies and the no ntinnitus frequency of 1,000 Hz. Results: There were significant differences in RTs in the experimental grou p and in the control group not only for the tinnitus frequencies, but also for the nontinnitus frequency of 1,000 Hz. The experimental group had short er RTs than did the control group at sensation levels (SLs) near the thresh old, with no significant differences between groups at sound stimuli in the suprathreshold intensity range. Conclusions: It is assumed that the above-mentioned reduction in RTs shows a dysfunction of cochlear mechanisms contributing to tinnitus. Conversely, tinnitus also can be considered as an additional auditory input leading to shorter RTs at SLs near the threshold. The current study suggests that the reaction time procedure to auditory stimuli offers complementary informatio n on tinnitus sensation and might be a valuable method in demonstrating gen eral differences and tendencies that have been neglected so far. Analysis f or the mechanisms of tinnitus sensation allows for the possibility of facil itating the process of tinnitus habituation and, ultimately, the relief fro m it.