Level Effects on Acceptance of Noise in Hearing Aid Users

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Level Effects on Acceptance of Noise in Hearing
Aid Users

• by Mindy Freyaldenhoven
• November 2006

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Background

• Acceptable noise level (ANL) is a measure of an
  individuals willingness to accept background
  noise while listening to speech.
• ANL MCL - BNL
• Nabelek et al, 1991

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ANL Research

• ANL is not related to age, gender, hearing
  sensitivity, or speech perception in noise
  scores.
• ANL is not related to amplification, but it is
  related to pattern of hearing aid use.
• ANL can predict hearing aid use w/ 85 accuracy.
• Freyaldenhoven Smiley, in press Nabelek et al,
  2006 Rogers et al, 2003

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ANL Research

• ANLs are directly related to the presentation
  level of the speech stimuli in listeners w/
  normal hearing.
• Listeners w/ small ANLs have a small ANL growth,
  and listeners w/ large ANLs have a larger ANL
  growth.
• Franklin et al, 2006 Tampas Harkrider, 2006

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Potential Limitations of ANL

• Assumes that individuals only listen at one
  level, their MCL.
• Predicts hearing aid success w/ 85 accuracy
  15 error rate.
• The unsuccessful HA user group contains both
  part-time and non-users of HAs.
• ANL is not a good predictor for listeners w/ the
  most prevalent ANLs.

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Purpose

• Experiment I To determine if the effects of
  speech presentation level on acceptance of noise
  can better differentiate full-time, part-time,
  and non-users of hearing aids.
• Experiment II To determine if the effects of
  speech presentation level on acceptance of noise
  are a better predictor of hearing aid use for
  full-time, part-time, and non-users of hearing
  aids.

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Methods Participants

• 69 adults w/ hearing impairment
• Group A Full-time HA users (N 25)
• Group B Part-time HA users (N 21)
• Group C Non-users of HAs (N 23)

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Methods Participants
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Methods Procedures

• Unaided ANLs
• MCL
• Conventional ANL
• 8 fixed speech presentation levels (40, 45, 50,
  55, 60, 65, 70, 75 dB HL)
• Global ANL (ANL averaged across 8 fixed
  presentation levels)
• ANL Growth (slope of ANL function)
• Speech noise stimuli ? 0 azimuth

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Experiment I Results

• Research Question
• Can the effects of speech presentation level on
  acceptance of noise differentiate full-time,
  part-time, and non-users of hearing aids?

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Experiment I Results

• Conventional ANLs and global ANLs
• Significantly smaller for full-time hearing aid
  users than part-time or non-users however,
  part-time non-users could not be
  differentiated.
• ANL growth
• Significantly smaller for full-time hearing aid
  users than non-users however, part-time users
  could not be differentiated from the other 2
  groups.

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Experiment I Results
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Experiment I Results

• Secondary Analysis
• Can ANL measured at a fixed presentation levels
  differentiate the 3 hearing aid groups?
• ANL measured at 65, 70, 75 dB HL categorized
  listeners into the 3 hearing aid groups in the
  same manner as conventional ANL.

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Experiment II Results

• Research Question
• Are the effects of speech presentation level on
  acceptance of noise a better predictor of hearing
  aid use for full-time, part-time, and non-users
  of hearing aids.

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Experiment II Results

• Global ANL ANL for presentation levels from 65
  75 dB HL differentiated the hearing aid groups
  similarly to conventional ANL (Note ANL growth
  was also added to the analysis).
• Groups were redefined into successful
  unsuccessful hearing aid users.

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Experiment II Results

• Logistic regression analyses showed conventional
  ANL predicted hearing aid use with 68 accuracy.
• Accuracy decreased for global ANL ANL growth.
• Accuracy slightly increased for ANLs for
  presentation levels from 65 75 dB HL.

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Experiment I Conclusions/Implications

• Can the effects of speech presentation level on
  acceptance of background noise differentiate
  full-time, part-time, and non-users of hearing
  aids?
• Global ANLs differentiated the hearing aid groups
  in the same manner as conventional ANLs.
• ANL growth only differentiated full-time
  non-users of hearing aids.
• Neither global ANL or ANL growth differentiated
  part-time from non-users.

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Experiment I Conclusions/Implications

• Conventional ANLs highly correlated with ANLs for
  presentation levels of 65, 70, 75 dB HL.
• Indicating ANLs at fixed levels (65 75 dB HL)
  may provide similar information to conventional
  ANL.

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Experiment II Conclusions/Implications

• Are the effects of speech presentation level on
  acceptance of noise a better predictor of hearing
  aid use for full-time, part-time, and non-users
  of hearing aids?
• Conventional ANL predicted HA use w/ 68
  accuracy.
• Accuracy decreased for global ANL ANL growth
• These results indicate that the effects of speech
  presentation level on acceptance of noise is not
  a better indicator of hearing aid use than
  conventional ANL.

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Experiment II Conclusions/Implications

• ANL growth
• May help categorize people with mid-range ANLs.
• Individual data analysis showed
• It is possible that the effect of speech
  presentation level on acceptance of noise may aid
  in separating listeners with mid-range ANLs.

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Questions?
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References

• Franklin, C.A., Thelin, J.W., Nabelek, A.K.,
  Burchfield, S.B. (2006). The effect of speech
  presentation level on acceptance of background
  noise in normal-hearing listeners. Journal of
  the American Academy of Audiology 17, 141-146.
• Freyaldenhoven, M.C., Smiley, D.F. (in press).
  Acceptance of background noise in children with
  normal hearing. Journal of Education Audiology.
• Nabelek, A.K., Tucker, F.M., Letowski, T.R.
  (1991). Toleration of background noises
  Relationship with patterns of hearing aid use by
  elderly persons. Journal of Speech and Hearing
  Research, 34, 679-685.
• Nabelek, A.K., Freyaldenhoven, M.C., Tampas,
  J.W., Burchfield, S.B. (2006). Acceptable noise
  level as a predictor of hearing aid use. Journal
  of the American Academy of Audiology 17, 635-649.
  
• Rogers, D.S., Harkrider, A.W., Burchfield, S.B.,
  Nabelek, A.K. (2003). The influence of
  listener's gender on the acceptance of background
  noise. Journal of the American Academy of
  Audiology, 14, 374-385.
• Tampas, J.W. Harkrider, A.W. (2006). Auditory
  evoked potentials in females with high and low
  acceptance of background noise when listening to
  speech. Journal of the Acoustical Society of
  America, 119(3), 1548-1561.