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DISCUSSION
In this study, the LSP (Lists of Sentences in Portuguese) test was used, with the noise on the CD contained in the test itself and an added step with another masking noise contained in the audiometer, the speech noise. The two noises were used due to the fact that auditory perception is different for noises with different spectra. The performance of the tinnitus group presented with worse performance for both noises; however, the difference was only significant when using speech-noise noise. In comparing the responses from both groups to the two noises, it is possible to state that the study conditions with the speech-noise were more difficult than were the conditions with the noise on the CD. Both groups needed a more favorable signal/noise ratio for recognizing 50% of sentences with speech-noise noise as compared to the noise recorded on the CD. Similar results have also been presented elsewhere and similar data have been reported in other studies. With regard to the psychoacoustic measurements of tinnitus and the level of annoyance as measured by the THI, as in other studies, no correlation could be established.
In a study in which the Threshold Equalizing Noise (TEN) test was used in order to investigate the performance in identifying target sounds in the presence of noise, the thresholds obtained in the presence of ipsilateral noise were statistically higher (worse) in the tinnitus group than in the control group. The authors point out that it was possible to observe that the target tone in the tinnitus group did not benefit from unfavorable listening conditions, unlike what was observed in the control group, in which the thresholds remained practically unchanged with the introduction of noise.
Communication difficulties, in the majority of patients with tinnitus, are typically attributed to poor performance in speech perception, caused by hearing loss. The effect of tinnitus on speech perception, without hearing loss, is still unclear, indicating that, in noisy environments, individuals with tinnitus appear to have a lower speech recognition capacity than those without tinnitus, as observed in this study. These data add to the evidence that the effect of tinnitus on the perception of speech or pure-tone in the presence of noise is in fact negatively manifested, compromising the performance of individuals in these situations. The results obtained in the present study confirm this premise.