Preferred Low- and High-Frequency Compression Ratios among Hearing Aid Users with Moderately Severe to Profound Hearing Loss

2007 ◽  
Vol 18 (01) ◽  
pp. 017-033 ◽  
Author(s):  
Gitte Keidser ◽  
Harvey Dillon ◽  
Ole Dyrlund ◽  
Lyndal Carter ◽  
David Hartley
Keyword(s):  
Hearing Loss ◽  
High Frequency ◽  
Hearing Aid ◽  
Low Frequency ◽  
Fine Tuning ◽  
Adaptive Procedure ◽  
Profound Hearing Loss ◽  
Low Frequencies ◽  
Frequency Compression ◽  
Fast Acting

This study aimed to determine the low- and high-frequency compression ratios of a fast-acting device that were preferred by people with moderately severe to profound hearing loss. Three compression ratios (1:1, 1.8:1, and 3:1) were combined in the low and high frequencies to produce nine schemes that were evaluated pair-wise for three weeks in the field using an adaptive procedure. The evaluation was performed by 21 experienced hearing aid users with a moderately severe to profound hearing loss. Diaries and an exit interview were used to monitor preferences. Generally, the subjects preferred lower compression ratios than are typically prescribed, especially in the low frequencies. Specifically, 11 subjects preferred linear amplification in the low frequencies, and 14 subjects preferred more compression in the high than in the low frequencies. Preferences could not be predicted from audiometric data, onset of loss, or past experience with amplification. The data suggest that clients with moderately severe to profound hearing loss should be fitted with low-frequency compression ratios in the range 1:1 to 2:1 and that fine-tuning is essential. Este estudio trató de determinar las tasas de compresión de alta y baja frecuencia de un dispositivo de acción rápida, que resultara preferido por personas con hipoacusias moderadamente severas a profundas. Se combinaron tres tasas de compresión (1:1, 1.8:1, y 3:1) en las frecuencias graves y agudas para producir nueve esquemas que fueron evaluados en el campo, en pares, durante tres semanas, utilizando un procedimiento de adaptación. La evaluación fue realizada por 21 usuarios experimentados de audífono con hipoacusias moderadamente severas a profundas. Se usaron diarios y un cuestionario final para monitorear las preferencias. Generalmente, los sujetos prefirieron menores tasas de compresión de lo que típicamente se prescribe, especialmente en las bajas frecuencias. Específicamente, 11 sujetos prefirieron la amplificación lineal en las frecuencias graves y 14 sujetos prefirieron más compresión en las frecuencias altas. Las preferencias no podían predecirse a partir de los datos audiométricos, del inicio de la pérdida, o por experiencias anteriores con amplificación. Los datos sugieren que los clientes con hipoacusias moderadamente severas a profundas, deberían adaptarse con tasas de compresión en las frecuencias graves en el rango de 1:1 a 2:1, y que un ajuste fino es esencial.

scholarly journals The Use of Frequency Lowering Technology in the Treatment of Severe-to-Profound Hearing Loss: A Review of the Literature and Candidacy Considerations for Clinical Application

2018 ◽  
Vol 39 (04) ◽  
pp. 377-389 ◽  
Author(s):  
Susan Scollie ◽  
Danielle Glista
Keyword(s):  
Hearing Loss ◽  
Hearing Impairment ◽  
Clinical Application ◽  
Current Literature ◽  
High Frequency ◽  
Hearing Aid ◽  
Verification And Validation ◽  
Review Of The Literature ◽  
Profound Hearing Loss

AbstractThis article provides a review of the current literature on the topic of frequency lowering hearing aid technology specific to the treatment of severe and profound levels of hearing impairment in child and adult listeners. Factors to consider when assessing listener candidacy for frequency lowering technology are discussed. These include factors related to audiometric assessment, the listener, the type of hearing aid technology, and the verification and validation procedures that can assist in determining candidacy for frequency lowering technology. An individualized candidacy assessment including the use of real-ear verification measures and carefully chosen validation tools are recommended for listeners requiring greater audibility of high-frequency sounds, when compared with amplification via conventional hearing aid technology.

Pendred's Syndrome: A Study of Patients and Relatives

1995 ◽  
Vol 104 (12) ◽  
pp. 957-962 ◽  
Author(s):  
Musa N. Jamal ◽  
Mohammed A. Arnaout ◽  
Ribhi Jarrar
Keyword(s):  
Hearing Loss ◽  
Low Frequency ◽  
Sensorineural Hearing ◽  
The Other ◽  
Test Results ◽  
Profound Hearing Loss ◽  
Low Frequencies ◽  
Pendred’S Syndrome ◽  
Perchlorate Discharge Test ◽  
Discharge Test

Four families, 29 members, with Pendred's syndrome were studied to clarify hearing loss and hormonal status. The ages ranged fro 3 to 50 years. Complete Pendred's syndrome was found in 9 patients. They had bilateral profound hearing loss with residual hearing low frequencies. Goiter was diagnosed at the age of 1 to 14 years with a positive perchlorate discharge test. Twelve of the patient relatives showed partial Pendred's syndrome. Mild sensorineural hearing losses occurred in the low- and medium-range frequencies wi normal perchlorate discharge test results in 6 cases. The other 6 had a slight drop in the perchlorate discharge test results with norm hearing. Five subjects were normal and 3 had normal hormonal and normal perchlorate discharge test results, but were not teste audiologically. This paper shows that patients with Pendred's syndrome may have goiter at birth or develop it between 8 and 14 year that their deafness is bilateral and profound, and that their perchlorate discharge tests are positive. Relatives of Pendred's syndrorr patients showed mild low-frequency sensorineural hearing loss without goiter and normal perchlorate discharge test results in half tl cases, and a slight drop in the perchlorate discharge test results with normal hearing and without goiter in the other half. A correlatic between these findings and genetic studies needs further investigation.

scholarly journals Listening Effort and Speech Recognition with Frequency Compression Amplification for Children and Adults with Hearing Loss

2017 ◽  
Vol 28 (09) ◽  
pp. 823-837 ◽  
Author(s):  
Marc A. Brennan ◽  
Dawna Lewis ◽  
Ryan McCreery ◽  
Judy Kopun ◽  
Joshua M. Alexander
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
High Frequency ◽  
Hearing Aid ◽  
Nonsense Word ◽  
Spectral Distortion ◽  
Listening Effort ◽  
Frequency Compression ◽  
Low Pass ◽  
Adults And Children

AbstractNonlinear frequency compression (NFC) can improve the audibility of high-frequency sounds by lowering them to a frequency where audibility is better; however, this lowering results in spectral distortion. Consequently, performance is a combination of the effects of increased access to high-frequency sounds and the detrimental effects of spectral distortion. Previous work has demonstrated positive benefits of NFC on speech recognition when NFC is set to improve audibility while minimizing distortion. However, the extent to which NFC impacts listening effort is not well understood, especially for children with sensorineural hearing loss (SNHL).To examine the impact of NFC on recognition and listening effort for speech in adults and children with SNHL.Within-subject, quasi-experimental study. Participants listened to amplified nonsense words that were (1) frequency-lowered using NFC, (2) low-pass filtered at 5 kHz to simulate the restricted bandwidth (RBW) of conventional hearing aid processing, or (3) low-pass filtered at 10 kHz to simulate extended bandwidth (EBW) amplification.Fourteen children (8–16 yr) and 14 adults (19–65 yr) with mild-to-severe SNHL.Participants listened to speech processed by a hearing aid simulator that amplified input signals to fit a prescriptive target fitting procedure.Participants were blinded to the type of processing. Participants' responses to each nonsense word were analyzed for accuracy and verbal-response time (VRT; listening effort). A multivariate analysis of variance and linear mixed model were used to determine the effect of hearing-aid signal processing on nonsense word recognition and VRT.Both children and adults identified the nonsense words and initial consonants better with EBW and NFC than with RBW. The type of processing did not affect the identification of the vowels or final consonants. There was no effect of age on recognition of the nonsense words, initial consonants, medial vowels, or final consonants. VRT did not change significantly with the type of processing or age.Both adults and children demonstrated improved speech recognition with access to the high-frequency sounds in speech. Listening effort as measured by VRT was not affected by access to high-frequency sounds.

Effects of Reducing Low-Frequency Amplification on Consonant Perception in Quiet and Noise

1984 ◽  
Vol 27 (4) ◽  
pp. 483-493 ◽  
Author(s):  
Sandra Gordon-Salant
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aids ◽  
High Frequency ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Low Frequency ◽  
Identification Performance ◽  
Phonetic Feature ◽  
Consonant Recognition

The aim of this study was to assess the effect of low-frequency amplification on speech recognition performance by hearing-impaired listeners. Consonant identification performance by subjects with flat hearing losses and high-frequency hearing losses was assessed in three different hearing aid conditions, in quiet and noise. The experimental hearing aids all provided extra high-frequency amplification but differed in the amount of low-frequency amplification. The results showed that listeners with flat hearing losses benefited by low-frequency amplification, whereas subjects with high-frequency hearing losses exhibited deteriorating scores in conditions with greatest low-frequency amplification. Analyses of phonetic feature perception and individual consonant recognition scores revealed subtle interactions between hearing loss configuration and amplification contour.

Evaluation of Special Hearing Aids for Deaf Children

1971 ◽  
Vol 36 (4) ◽  
pp. 527-537 ◽  
Author(s):  
Norman P. Erber
Keyword(s):  
Hearing Aids ◽  
High Frequency ◽  
Hearing Aid ◽  
Low Frequency ◽  
Acoustic Stimulation ◽  
Deaf Children ◽  
Frequency Range ◽  
Frequency Limit ◽  
Unpublished Studies ◽  
Published Research

Two types of special hearing aid have been developed recently to improve the reception of speech by profoundly deaf children. In a different way, each special system provides greater low-frequency acoustic stimulation to deaf ears than does a conventional hearing aid. One of the devices extends the low-frequency limit of amplification; the other shifts high-frequency energy to a lower frequency range. In general, previous evaluations of these special hearing aids have obtained inconsistent or inconclusive results. This paper reviews most of the published research on the use of special hearing aids by deaf children, summarizes several unpublished studies, and suggests a set of guidelines for future evaluations of special and conventional amplification systems.

Modified Earpieces and CROS for High Frequency Hearing Losses

1968 ◽  
Vol 11 (1) ◽  
pp. 204-218 ◽  
Author(s):  
Elizabeth Dodds ◽  
Earl Harford
Keyword(s):  
Hearing Loss ◽  
Hearing Aids ◽  
High Frequency ◽  
Hearing Aid ◽  
Sound Field ◽  
Intensity Level ◽  
Test Results ◽  
High Frequency Hearing Loss ◽  
Increased Sensitivity ◽  
Difficult Cases

Persons with a high frequency hearing loss are difficult cases for whom to find suitable amplification. We have experienced some success with this problem in our Hearing Clinics using a specially designed earmold with a hearing aid. Thirty-five cases with high frequency hearing losses were selected from our clinical files for analysis of test results using standard, vented, and open earpieces. A statistical analysis of test results revealed that PB scores in sound field, using an average conversational intensity level (70 dB SPL), were enhanced when utilizing any one of the three earmolds. This result was due undoubtedly to increased sensitivity provided by the hearing aid. Only the open earmold used with a CROS hearing aid resulted in a significant improvement in discrimination when compared with the group’s unaided PB score under earphones or when comparing inter-earmold scores. These findings suggest that the inclusion of the open earmold with a CROS aid in the audiologist’s armamentarium should increase his flexibility in selecting hearing aids for persons with a high frequency hearing loss.

scholarly journals Earless toads sense low frequencies but miss the high notes

2017 ◽  
Vol 284 (1864) ◽  
pp. 20171670 ◽  
Author(s):  
Molly C. Womack ◽  
Jakob Christensen-Dalsgaard ◽  
Luis A. Coloma ◽  
Juan C. Chaparro ◽  
Kim L. Hoke
Keyword(s):  
High Frequency ◽  
Species Differences ◽  
Low Frequency ◽  
Auditory Brainstem ◽  
Low Frequencies ◽  
Hearing Sensitivity ◽  
Sensory Pathways ◽  
Airborne Sound ◽  
Vibrational Sensitivity ◽  
Species Specific

Sensory losses or reductions are frequently attributed to relaxed selection. However, anuran species have lost tympanic middle ears many times, despite anurans' use of acoustic communication and the benefit of middle ears for hearing airborne sound. Here we determine whether pre-existing alternative sensory pathways enable anurans lacking tympanic middle ears (termed earless anurans) to hear airborne sound as well as eared species or to better sense vibrations in the environment. We used auditory brainstem recordings to compare hearing and vibrational sensitivity among 10 species (six eared, four earless) within the Neotropical true toad family (Bufonidae). We found that species lacking middle ears are less sensitive to high-frequency sounds, however, low-frequency hearing and vibrational sensitivity are equivalent between eared and earless species. Furthermore, extratympanic hearing sensitivity varies among earless species, highlighting potential species differences in extratympanic hearing mechanisms. We argue that ancestral bufonids may have sufficient extratympanic hearing and vibrational sensitivity such that earless lineages tolerated the loss of high frequency hearing sensitivity by adopting species-specific behavioural strategies to detect conspecifics, predators and prey.

Observations on the Relations among Occlusion Effect, Compliance, and Vent Size

2002 ◽  
Vol 13 (01) ◽  
pp. 025-037 ◽  
Author(s):  
Roberto Carle ◽  
Søren Laugesen ◽  
Claus Nielsen
Keyword(s):  
Hearing Loss ◽  
Simple Model ◽  
Laboratory Experiment ◽  
Hearing Aid ◽  
Low Frequency ◽  
Minimum Size ◽  
Similar Relationship ◽  
Profound Influence ◽  
Occlusion Effect ◽  
Clinical Experiment

In a clinical experiment, it was found that there is a high correlation between the compliance measured by tympanometry and the minimum size of the earmold vent, which just solves the client's occlusion problem related to his/her own voice when using a hearing aid. For ears with sensorineural hearing losses, compliance explained 59 percent of the variation in vent size, whereas the average low-frequency hearing loss explained as little as 0.3 percent. In a laboratory experiment, the objective occlusion effect measured with the participants' own voices showed a similar relationship with compliance. Whereas the former relationship between compliance and vent size may be explained by a simple model, the latter relationship turns out to be the opposite of what a firstorder model predicts. Hence, compliance must be indicative of another aspect of the occlusion mechanism, which has a more profound influence on the observed occlusion effect than compliance itself.

scholarly journals The Nature of the Stochastic Wind Forcing of ENSO

2018 ◽  
Vol 31 (19) ◽  
pp. 8081-8099 ◽  
Author(s):  
Antonietta Capotondi ◽  
Prashant D. Sardeshmukh ◽  
Lucrezia Ricciardulli
Keyword(s):  
El Niño ◽  
High Frequency ◽  
El Nino ◽  
Southern Oscillation ◽  
Low Frequency ◽  
Kelvin Waves ◽  
Wind Forcing ◽  
Alternative View ◽  
Low Frequencies ◽  
Wind Events

El Niño–Southern Oscillation (ENSO) is commonly viewed as a low-frequency tropical mode of coupled atmosphere–ocean variability energized by stochastic wind forcing. Despite many studies, however, the nature of this broadband stochastic forcing and the relative roles of its high- and low-frequency components in ENSO development remain unclear. In one view, the high-frequency forcing associated with the subseasonal Madden–Julian oscillation (MJO) and westerly wind events (WWEs) excites oceanic Kelvin waves leading to ENSO. An alternative view emphasizes the role of the low-frequency stochastic wind components in directly forcing the low-frequency ENSO modes. These apparently distinct roles of the wind forcing are clarified here using a recently released high-resolution wind dataset for 1990–2015. A spectral analysis shows that although the high-frequency winds do excite high-frequency Kelvin waves, they are much weaker than their interannual counterparts and are a minor contributor to ENSO development. The analysis also suggests that WWEs should be viewed more as short-correlation events with a flat spectrum at low frequencies that can efficiently excite ENSO modes than as strictly high-frequency events that would be highly inefficient in this regard. Interestingly, the low-frequency power of the rapid wind forcing is found to be higher during El Niño than La Niña events, suggesting a role also for state-dependent (i.e., multiplicative) noise forcing in ENSO dynamics.

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