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Query: EC:2.3.1.107 (DAT)
 1,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ten teachers made recordings during one normal working day using a portable DAT recorder and a head-mounted microphone. In addition, the subjects filled in a questionnaire of signs of vocal fatigue. The speech samples were selected from the first and last lesson from three points representing the beginning, middle and end part of the lesson, respectively. To standardize the samples, 30 [a] vowels from stressed syllables were chosen for spectral analysis. The level of the fundamental and second formant regions (L1), the level of frequency ranges 2-5 kHz (L2) and 5-10 kHz (L5) were measured. From these measurements the parameters L1-L0, L1-L2 and L1-L5 were formed and used in the analyses as well as the energy levels below and above 1 kHz (alpha). Statistically significant changes were observed in the following parameters: the L1-L2 and L1-L5 differences, and the alpha ratio. In general, there was an increase in the energy content of the high frequency components due to vocal loading. The subjective reports revealed a statistically significant relationship with the spectral characteristics.
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PMID:Working-day effects on the spectral characteristics of teaching voice. 981 82

Preschool teachers are at risk for developing voice problems such as vocal fatigue and vocal nodules. The purpose of this report was to study preschool teachers' voice use during work. Ten healthy female preschool teachers working at daycare centers (DCC) served as subjects. A binaural recording technique was used. Two microphones were placed on both sides of the subject's head, at equal distance from the mouth, and a portable DAT recorder was attached to the subject's waist. Recordings were made of a standard reading passage before work (baseline) and of spontaneous speech during work. The recording technique allowed separate analyses of the level of the background noise, and of the subjects' voice sound pressure level, mean fundamental frequency, and total phonation time. Among the results, mean background noise level for the ten DCCs was 76.1 dBA (range 73.0-78.2), which is more than 20 dB higher than what is recommended where speech communication is important (50-55 dBA). The subjects spoke on an average of 9.1 dB louder (p < 0.0001), and with higher mean fundamental frequency (247 Hz) during work as compared to the baseline (202 Hz) (p < 0.0001). Mean phonation time for the group was 17%, which was considered high. It was concluded that preschool teachers do have a highly vocally demanding profession. Important steps to reduce the vocal loading for this occupation would be to decrease the background noise levels and include pauses so that preschool teachers can rest their voices.
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PMID:Vocal behavior and vocal loading factors for preschool teachers at work studied with binaural DAT recordings. 1239 88

An increase in fundamental frequency (F(0)) and in sound pressure level (SPL) has been reported both after vocal loading tests and after a teacher's working day. This increase has been found to be greater among teachers with fewer voice complaints. The present study investigated speech changes during a teacher's working day (a) in ordinary conditions and (b) when using electric sound amplification while teaching. Five Icelandic teachers (mean age 51 years) volunteered as subjects. Classroom speech was recorded with a portable DAT recorder and a head-mounted microphone first in ordinary conditions, and the next week while using electrical sound amplification. Recordings were made during the first and the last lesson of the hardest working day of the week. F(0) and SPL were analyzed. The subjects' comments were gathered by questionnaire. An increase in F(0) and SPL was found during the working day in both teaching conditions but the change was larger and for F(0) statistically significant when amplification was used. All 5 teachers reported less tiredness of the vocal mechanism when using amplification. The results support the suggestion that a vocal loading-related increase in F(0) and SPL is not merely a sign of vocal fatigue but may even reflect an adequate adaptation to loading. Situational factors cannot be ignored, however.
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PMID:Changes in teachers' speech during a working day with and without electric sound amplification. 1241 98

The present study investigated changes in the voice quality of teachers during a working day (a). in ordinary conditions and (b). when using electrical sound amplification while teaching. Classroom speech of 5 teachers was recorded with a portable DAT recorder and a head-mounted microphone during the first and the last lesson of a hard working day first in ordinary conditions and the following week using amplification. Long-term average spectrum and sound pressure level (SPL) analyses were made. The subjects' comments were gathered by questionnaire. Voice quality was evaluated by 2 speech trainers. With amplification, SPL was lower and the spectrum more tilted. Voice quality was evaluated to be better. The subjects reported less fatigue in the vocal mechanism. Spectral tilt decreased and SPL increased during the day. There was a tendency for perceived asthenia to decrease. No significant changes were observed in ordinary conditions. The acoustic changes seem to reflect a positive adaptation to vocal loading. Their absence may be a sign of vocal fatigue.
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PMID:Changes in teachers' voice quality during a working day with and without electric sound amplification. 1293 Oct 60