Limiares de reconhecimento de sentenças, em campo livre, na presença de ruído incidente de diferentes ângulos, em indivíduos normo-ouvintes

Abstract

The environmental noise interferes with different ways in the speech recognition depending on its inciding direction. Taking this into account, this study was developed with the aim of determining and comparing the sentence recognition thresholds in the noise, at the sound field, with the inciding noise from different angles, in normal-hearing individuals. The research was carried out from the application of Portuguese Sentence Lists Test (COSTA, 1998), in 38 younger adults, ranging from 18 to 27 years old. They were evaluated in an acoustical booth at the Phonoaudiology Attendance Service of the Universidade Federal de Santa Maria, during the period from June to November of 2004. For the subjects evaluation, the sentences were always presented in 0º-0º azimuth, and the noise in 0º-0°, 0°-90°, 0°-180° and 0°-270° azimuth., in a fixed loudness of 65 dB A. The results analysis shows that the signal to noise ratios in witch the sentence recognition thresholds were obtained, to these inciding angles, were, respectively: -7,56 , -11,11 , -9,45 and –10,43 dB. It was also possible to verify that there was a statistically significant difference among the signal to noise ratios in these evaluation conditions: 0º - 0º X 0º - 90º; 0º - 0º X 0º - 180º; 0º- 0º X 0º-270º and 0º - 90º X 0º - 180º.