title: Benefits of adaptive FM systems on speech recognition in noise for listeners who use hearing aids.
abstract: OBJECTIVE
  To compare the benefits of adaptive FM and fixed FM systems through measurement of speech recognition in noise with adults and students in clinical and real-world settings.
  
  
  METHODS
  Five adults and 5 students with moderate-to-severe hearing loss completed objective and subjective speech recognition in noise measures with the 2 types of FM processing. Sentence recognition was evaluated in a classroom for 5 competing noise levels ranging from 54 to 80 dBA while the FM microphone was positioned 6 in. from the signal loudspeaker to receive input at 84 dB SPL. The subjective measures included 2 classroom activities and 6 auditory lessons in a noisy, public aquarium.
  
  
  RESULTS
  On the objective measures, adaptive FM processing resulted in significantly better speech recognition in noise than fixed FM processing for 68- and 73-dBA noise levels. On the subjective measures, all individuals preferred adaptive over fixed processing for half of the activities. Adaptive processing was also preferred by most (8-9) individuals for the remaining 4 activities.
  
  
  CONCLUSIONS
  The adaptive FM processing resulted in significant improvements at the higher noise levels and was preferred by the majority of participants in most of the conditions.
authors.affiliation: University of Texas at Dallas, Callier Center for Communication Disorders, USA. thib@utdallas.edu
authors.forename: Linda
authors.initials: L
authors.lastname: Thibodeau
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004867:Equipment Design; D005260:Female; D006310:Hearing Aids; D006312:Hearing Loss, Bilateral / Q000175:diagnosis / Q000534:rehabilitation*; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000534:rehabilitation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D010470:Perceptual Masking; D012931:Social Environment; D013069:Speech Reception Threshold Test; D055815:Young Adult