title: Effects of Long-Term Speech-in-Noise Training in Air Traffic Controllers and High Frequency Suppression. A Control Group Study.
abstract: OBJECTIVE
  To evaluate 1) if air traffic controllers (ATC) perform better than non-air traffic controllers in an open-set speech-in-noise test because of their experience with radio communications, and 2) if high-frequency information (>8000 Hz) substantially improves speech-in-noise perception across populations.
  
  
  METHODS
  The control group comprised 28 normal-hearing subjects, and the target group comprised 48 ATCs aged between 19 and 55 years who were native Spanish speakers. The hearing -in-noise abilities of the two groups were characterized under two signal conditions: 1) speech tokens and white noise sampled at 44.1 kHz (unfiltered condition) and 2) speech tokens plus white noise, each passed through a 4th order Butterworth filter with 70 and 8000 Hz low and high cutoffs (filtered condition). These tests were performed at signal-to-noise ratios of +5, 0, and -5-dB SNR.
  
  
  RESULTS
  The ATCs outperformed the control group in all conditions. The differences were statistically significant in all cases, and the largest difference was observed under the most difficult conditions (-5 dB SNR). Overall, scores were higher when high-frequency components were not suppressed for both groups, although statistically significant differences were not observed for the control group at 0 dB SNR.
  
  
  CONCLUSIONS
  The results indicate that ATCs are more capable of identifying speech in noise. This may be due to the effect of their training. On the other hand, performance seems to decrease when the high frequency components of speech are removed, regardless of training.
authors.affiliation: Head and Neck Department, Psychoacoustics Lab, Complejo Hospitalario Universitario Insular Materno-Infantil de Gran Canaria, Avenida Marítima del Sur, Las Palmas, Spain. mtperezzaballos@gmail.com.
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Pérez Zaballos
authors.forename: Ángel
authors.initials: Á
authors.lastname: Ramos de Miguel
authors.forename: Daniel
authors.initials: D
authors.lastname: Pérez Plasencia
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Zaballos González
authors.forename: Ángel
authors.initials: Á
authors.lastname: Ramos Macías
mesh_terms: D000293:Adolescent; D000328:Adult; D001359:Aviation; D016022:Case-Control Studies; D006801:Humans; D008875:Middle Aged; D009622:Noise; D016273:Occupational Exposure; D011571:Psychoacoustics; D013067:Speech Perception; D055815:Young Adult