Hearing Aids Performance in Hypobaric Environments

2021 ◽  
Vol 92 (9) ◽  
pp. 738-743
Author(s):  
Marco Lucertini ◽  
Filippo Sanjust ◽  
Roberto Manca ◽  
Luigi Cerini ◽  
Lorenzo Lucertini ◽  
...  
Keyword(s):  
High Altitude ◽  
Hearing Aids ◽  
Ambient Air ◽  
Recording System ◽  
Simulated Altitude ◽  
Acoustic Transducers ◽  
Before And After ◽  
Rapid Decompression ◽  
Pressure Changes ◽  
First Session

OBJECTIVE: High altitudes imply exposure to a decreased ambient air pressure. Such a situation may also alter the performance of acoustic transducers using vibrating diaphragms due to air rarefaction. This study aimed at analyzing the performance at high altitude of hearing aids (HAs) where mechano-electric and electro-mechanic transducers are used. METHODS: A hypobaric chamber was used to perform two separated experimental sessions. In the first one two commercial models of HAs were exposed to a simulated altitude of 25,000 ft (7620 m) and to a subsequent rapid decompression profile, with a rapid climb (< 3 s) from 8000 (2438 m) to 25,000 ft. The second session separately analyzed the performance of microphone and receiver at an altitude of 9000 and 15,000 ft (2743 and 4572 m). Before and after the first session, the HAs were tested with an electronic ear while a dedicated recording system was used in the second session. RESULTS: No HA damage or dysfunction was detected during the first session. In the second one, the microphone showed a mild decrease of its output, while the receiver exhibited a much higher reduction of its output. CONCLUSION: Our findings highlight the safe use of HAs even under extreme environmental pressure changes. For altitudes exceeding 10,000 ft (3048 m), a recalibration of the HAs output via a dedicated program may be suggested. Lucertini M, Sanjust F, Manca R, Cerini L, Lucertini L, Sisto R. Hearing aids performance in hypobaric environments. Aerosp Med Hum Perform. 2021; 92(9):738743.

Use of a Mild-Gain Hearing Aid by Middle-Age Normal-Hearing Adults Who Do and Do Not Self-Report Trouble Hearing in Background Noise

2020 ◽  
Vol 29 (3) ◽  
pp. 419-428
Author(s):  
Jasleen Singh ◽  
Karen A. Doherty
Keyword(s):  
Hearing Aids ◽  
Background Noise ◽  
Middle Age ◽  
Hearing Aid ◽  
Normal Hearing ◽  
Self Report ◽  
Hearing Aid Use ◽  
Hearing Handicap ◽  
Before And After ◽  
Hearing Problems

Purpose The aim of the study was to assess how the use of a mild-gain hearing aid can affect hearing handicap, motivation, and attitudes toward hearing aids for middle-age, normal-hearing adults who do and do not self-report trouble hearing in background noise. Method A total of 20 participants (45–60 years of age) with clinically normal-hearing thresholds (< 25 dB HL) were enrolled in this study. Ten self-reported difficulty hearing in background noise, and 10 did not self-report difficulty hearing in background noise. All participants were fit with mild-gain hearing aids, bilaterally, and were asked to wear them for 2 weeks. Hearing handicap, attitudes toward hearing aids and hearing loss, and motivation to address hearing problems were evaluated before and after participants wore the hearing aids. Participants were also asked if they would consider purchasing a hearing aid before and after 2 weeks of hearing aid use. Results After wearing the hearing aids for 2 weeks, hearing handicap scores decreased for the participants who self-reported difficulty hearing in background noise. No changes in hearing handicap scores were observed for the participants who did not self-report trouble hearing in background noise. The participants who self-reported difficulty hearing in background noise also reported greater personal distress from their hearing problems, were more motivated to address their hearing problems, and had higher levels of hearing handicap compared to the participants who did not self-report trouble hearing in background noise. Only 20% (2/10) of the participants who self-reported trouble hearing in background noise reported that they would consider purchasing a hearing aid after 2 weeks of hearing aid use. Conclusions The use of mild-gain hearing aids has the potential to reduce hearing handicap for normal-hearing, middle-age adults who self-report difficulty hearing in background noise. However, this may not be the most appropriate treatment option for their current hearing problems given that only 20% of these participants would consider purchasing a hearing aid after wearing hearing aids for 2 weeks.

Volume receptors in guinea pig labyrinth: relevance with respect to ADH and Na control

1989 ◽  
Vol 257 (3) ◽  
pp. F341-F346 ◽  
Author(s):  
E. Bartoli ◽  
A. Satta ◽  
F. Melis ◽  
M. A. Caria ◽  
W. Masala ◽  
...  
Keyword(s):  
Inner Ear ◽  
Guinea Pigs ◽  
Control Mechanism ◽  
Extracellular Fluid ◽  
Urine Osmolality ◽  
Neural Pathways ◽  
Group Of Seven ◽  
Before And After ◽  
Pressure Changes ◽  
Inner Ear Pressure

We tested the hypothesis that changes in extracellular fluid volume are reflected by pressure changes within structures of the inner ear and that through neural pathways, a control mechanism exerts an influence on antidiuretic hormone (ADH) release and Na excretion. The study was performed on 35 guinea pigs. In protocol 1, 13 animals were studied before and after decompression of the inner ear by bilateral fluid withdrawal in an experimental setting of sustained isotonic expansion that kept the osmoreceptor partially activated and the intrathoracic volume receptors suppressed. A group of six sham-operated animals served as control. In protocol 2, nine animals were studied before and after a unilateral rise in their inner ear pressure during slightly hypertonic low-rate infusions that kept the osmoreceptor and thoracic volume receptors stimulated. A group of seven sham-operated guinea pigs served as controls. Decompression of the inner ear was attended by a rise in plasma ADH from 11.9 +/- 2.4 to 29.1 +/- 6.9 pg/ml, in urine osmolality (Uosmol) from 470 +/- 48 to 712 +/- 46 mosmol/kg (P less than 0.001), and a fall in urine flow rate (V) from 184 +/- 47 to 71 +/- 11 microliters/min (P less than 0.01), whereas plasma Na (PNa) and osmolality (Posmol) did not change. During inner ear hypertension, plasma ADH fell from 25.6 +/- 3.9 to 18.4 +/- 3.1, Uosmol from 829 +/- 58 to 627 +/- 43 (P less than 0.001), and V rose from 51 +/- 11 to 130 +/- 23 (P less than 0.001), whereas glomerular filtration rate, PNa, and Posmol did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Seasonal and Spatial Variation of Volatile Organic Compounds in Ambient Air of Almaty City, Kazakhstan

Atmosphere ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1592
Author(s):  
Olga P. Ibragimova ◽  
Anara Omarova ◽  
Bauyrzhan Bukenov ◽  
Aray Zhakupbekova ◽  
Nassiba Baimatova
Keyword(s):  
Air Pollution ◽  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Power Plants ◽  
Ambient Air ◽  
Spatial Variations ◽  
Primary Sources ◽  
Volatile Organic ◽  
Seasonal And Spatial Variations ◽  
Before And After

Air pollution is one of the primary sources of risk to human health in the world. In this study, seasonal and spatial variations of multiple volatile organic compounds (VOCs) were measured at six sampling sites in Almaty, Kazakhstan. The seasonal and spatial variations of 19 VOCs were evaluated in 2020, including the periods before and after COVID-19 lockdown. The concentrations of 9 out of 19 VOCs had been changed significantly (p < 0.01) during 2020. The maximum concentrations of total VOCs (TVOCs) were observed on 15, 17, and 19 January and ranged from 233 to 420 µg m−3. The spatial distribution of TVOCs concentrations in the air during sampling seasons correlated with the elevation and increased from southern to northern part of Almaty, where Combined Heat and Power Plants are located. The sources of air pollution by VOCs were studied by correlations analysis and BTEX ratios. The ranges of toluene to benzene ratio and benzene, toluene, and ethylbenzene demonstrated two primary sources of BTEX in 2020: traffic emissions and biomass/biofuel/coal burning. Most of m-, p-xylenes to ethylbenzene ratios in this study were lower than 3 in all sampling periods, evidencing the presence of aged air masses at studied sampling sites from remote sources.

scholarly journals A Study on the Preferred Real-Ear Insertion Gain of Multi-Channel Hearing Aid for the Korean with Sensorineural Hearing Loss

2020 ◽  
Vol 16 (2) ◽  
pp. 85-94
Author(s):  
Eojini Bang ◽  
Kyoungwon Lee
Keyword(s):  
Word Recognition ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Hearing Aid Fitting ◽  
High Frequencies ◽  
Frequency Bands ◽  
Before And After ◽  
Fitting Procedures ◽  
Linear Version ◽  
Gain Adjustment

Purpose: This study aimed to compare the preferred real-ear insertion gain for Korean (PREIG-K) wearing multi-channel hearing aid with the National Acoustics Laboratories-Non-Linear version 2 (NAL-NL2; National Acoustic Laboratories) gains in order to develop Korean hearing aid fitting formula.Methods: A total of thirty one (62 ears) Korean hearing aid users were included in this study. All subjects wore in-the-canal or custom hearing aids in both ears. Individual hearing aid fitting procedures involved to adjust the gains for 50, 65, and 80 dB sound pressure level of speech across low, high, and wideband frequency bands based on participant’s subjective responses. In addition, only the high frequency bands of 1 kHz or more of the PREIG-K were re-adjusted to be the same as NAL-NL2 gain and then the word recognition scores (WRSs) were compared before and after the adjusting gain. Results: The results showed that the PREIG-K increased up to 1.5 kHz with the maximum amount, then the PREIG-K decreased across the frequencies. For all half octave frequencies, the PREIG-Ks were substantially less than the NAL-NL2. When the PREIG-K of high frequencies were re-adjusted same as the NAL-NL2 gains, the WRSs of the PREIG-K were not significantly different before and after gain adjustment. The slopes up to 1.5 kHz frequencies of the PREIG-K were steeper than the slopes of NAL-NL2 gain, however similar to the slope of manufactures’ fitting formulae.Conclusion: The development of an effective hearing aid fitting formula for improving the communication abilities of hearing-impaired Korean will require further experiments considering the language, physical characteristics, and word recognition used by Koreans.

Working Memory, Sleep, and Hearing Problems in Patients with Tinnitus and Hearing Loss Fitted with Hearing Aids

2017 ◽  
Vol 28 (02) ◽  
pp. 141-151 ◽  
Author(s):  
Reza Zarenoe ◽  
Mathias Hällgren ◽  
Gerhard Andersson ◽  
Torbjörn Ledin
Keyword(s):  
Working Memory ◽  
Hearing Loss ◽  
Cognitive Function ◽  
Sleep Quality ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Reading Span ◽  
Full Sample ◽  
Before And After ◽  
Hearing Problems

Background: Tinnitus is a common condition and there is a need to evaluate effects of tinnitus management in relation to moderating factors such as degree of hearing loss. As it is possible that tinnitus influences concentration, and thus is likely to disturb cognitive processing, the role of cognitive functioning also needs to be investigated. Purpose: To compare a group of patients with sensorineural hearing loss and tinnitus to a control group with only sensorineural hearing loss (and no tinnitus). To investigate working memory, sleep, and hearing problems measured before and after hearing rehabilitation. Research Design: A prospective study. Study Sample: The sample consisted of 100 patients, 50 with hearing loss and tinnitus, and 50 controls with hearing loss but no tinnitus. All patients were between 40 and 82 yr old and had a pure-tone average (PTA; average of 0.5, 1, 2, and 4 kHz) <70 dB HL. Intervention: Patients were tested before and after rehabilitation with hearing aids with regard to their working memory capacity, sleep quality, hearing problems, speech recognition, and tinnitus annoyance. Data Collection and Analysis: Eight patients dropped out of the study. Thus, a total of 92 patients were included for analysis, with 46 in each group. As a consequence of unplanned age and PTA differences between the groups, an age-matched subsample (n = 30 + 30) was selected for further analysis. Tests including the Reading Span, Hearing-in-Noise Test (HINT), Tinnitus Handicap Inventory (THI), Hearing Handicap Inventory for the Elderly (HHIE), and Pittsburgh Sleep Quality Index (PSQI) were administered before and after hearing aid rehabilitation. Results: There were no between-group differences at baseline in the full sample (n = 92), with the exception of the THI (p < 0.001) and the PSQI (p < 0.002), on which the hearing loss and tinnitus group had significantly higher scores. Pre/post changes were significant for both groups on the Reading Span, and HHIE. However, these improvements were significantly larger for the patients in the hearing loss and tinnitus group on the Reading Span test (p < 0.001) and the PSQI (p < 0.001). Patients with tinnitus and hearing loss also exhibited significantly improved THI scores at follow-up, compared to baseline (p < 0.001).We conducted the same analyses for the age-matched subsample (n = 30 + 30). For the baseline data, only the THI (p < 0.001) and the PSQI (p < 0.015) difference remained significant. With regard to the pre/post changes, we found the same differences in improvement in Reading Span (p < 0.001) and the PSQI (p < 0.015) as in the full sample. Conclusions: Patients with tinnitus benefited from hearing aid rehabilitation. The observed differences in cognitive function were unexpected, and there were larger score improvements on the Reading Span test in the hearing loss and tinnitus group than in the hearing loss group. Patients with tinnitus and hearing loss may receive extra benefit in terms of cognitive function following hearing aid rehabilitation.

Adaptations to High-Altitude Hypoxia

2021 ◽  
Author(s):  
Cynthia M. Beall ◽  
Kingman P. Strohl
Keyword(s):  
High Altitude ◽  
Oxygen Delivery ◽  
Hemoglobin Concentration ◽  
Barometric Pressure ◽  
Ambient Air ◽  
Extreme Environment ◽  
Indigenous Populations ◽  
East African ◽  
Short Term

Biological anthropologists aim to explain the hows and whys of human biological variation using the concepts of evolution and adaptation. High-altitude environments provide informative natural laboratories with the unique stress of hypobaric hypoxia, which is less than usual oxygen in the ambient air arising from lower barometric pressure. Indigenous populations have adapted biologically to their extreme environment with acclimatization, developmental adaptation, and genetic adaptation. People have used the East African and Tibetan Plateaus above 3,000 m for at least 30,000 years and the Andean Plateau for at least 12,000 years. Ancient DNA shows evidence that the ancestors of modern highlanders have used all three high-altitude areas for at least 3,000 years. It is necessary to examine the differences in biological processes involved in oxygen exchange, transport, and use among these populations. Such an approach compares oxygen delivery traits reported for East African Amhara, Tibetans, and Andean highlanders with one another and with short-term visitors and long-term upward migrants in the early or later stages of acclimatization to hypoxia. Tibetan and Andean highlanders provide most of the data and differ quantitatively in biological characteristics. The best supported difference is the unelevated hemoglobin concentration of Tibetans and Amhara compared with Andean highlanders as well as short- and long-term upward migrants. Moreover, among Tibetans, several features of oxygen transfer and oxygen delivery resemble those of short-term acclimatization, while several features of Andean highlanders resemble the long-term responses. Genes and molecules of the oxygen homeostasis pathways contribute to some of the differences.

scholarly journals Hearing Rehabilitation through Bone-Conducted Sound Stimulation: Preliminary Results

2018 ◽  
Vol 23 (01) ◽  
pp. 012-017 ◽  
Author(s):  
Fayez Bahmad Jr ◽  
Carolina Cardoso ◽  
Fernanda Caldas ◽  
Monique Barreto ◽  
Anacléia Hilgenberg ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Speech Perception ◽  
Hearing Aids ◽  
Subcutaneous Tissue ◽  
Bone Conduction ◽  
Free Field ◽  
Pure Tone Audiometry ◽  
Skin Impedance ◽  
Significant Difference ◽  
Before And After

Introduction The bone-anchored hearing aid (BAHA) is a bone conduction system that transmits the sound directly to the inner ear by surpassing the skin impedance and the subcutaneous tissue. It is indicated for patients with mixed, conductive and unilateral sensorineural hearing loss who did not benefit from conventional hearing aids (HAs). Although the benefits from BAHA are well demonstrated internationally, this field still lacks studies in Brazil. Objective To assess the auditory rehabilitation process in BAHA users through audiological, speech perception and tinnitus aspects. Methods Individuals with hearing loss were assessed before and after the implantation. The participants were subjected to pure tone audiometry in free field, functional gain audiometry, speech perception tests, tinnitus handicap inventory (THI) in open format, and to the visual analog scale (VAS). Results It was found that the participants benefited from the use of BAHA. The difference in the performance of the participants before and after the BAHA surgery was significant in terms of hearing acuity. There was no statistically significant difference in the speech perception tests. The tinnitus assessment showed that 80% of the participants scored slight tinnitus severity in THI after using a BAHA. Eighty percent of the participants classified their tinnitus as absent to mild in the VAS after the surgery. Conclusion Based on the results of the current study, we can conclude that the participants improved both the auditory perception and the tinnitus handicap.

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