ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

The effect of setting the gain control of a hearing aid to a position just lower than that required to produce audible oscillation was investigated in the condition where the main feedback pathway was an earmold vent of either diagonal (side-branch) or parallel configuration. Results indicated that, with this gain control setting, suboscillatory feedback effects were superimposed on the filtering effect of the earmold vent. The outcome was the formation of spurious peaks in the frequency response of the hearing aid. Most of the data were collected using a KEMAR manikin and the effects were confirmed by measurements made in real ear canals. It is recommended that this gain control setting be avoided in hearing aid fitting.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Paired comparison perception and preference judgments of hearing aid processed music were examined under conditions of extended and reduced high and low-frequency ranges. The performance of 20 subjects with mild to moderate hearing impairment was compared with an equal number of normal hearing controls. Subjects with normal hearing indicated perception of and preference for extended ranges for both high and low frequencies. However, the perception and preference judgments of hearing-impaired subjects were essentially random for the high-frequency ranges; but accurate perception and preference was found for extended low-frequency adjustments. Implications for hearing aid design and use are discussed.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Responses to a hearing aid usage questionnaire were received from 128 patients with high-frequency sensorineural hearing loss fitted monaurally with contralateral routing of signals (CROS) or ipsilateral routing of signals (IROS) hearing aids. Functional benefits were demonstrated by wearing the instruments 8 to 9 hr/day, use of the aids about 60% of the time in communicative situations, subjective benefit judgments of 5 to 9 on a 10-point scale, improved subjective sound localization, and improved clarity of speech with the hearing aids. Although CROS and IROS fittings could not be separated on the basis of these factors, considerably more complaints were reported by the CROS wearers, and many of these related to auditory factors. Both CROS and IROS fittings appear to be effective approaches to the patient with high-frequency hearing loss. However, in light of the fewer complaints by the IROS group, and the fact that a large proportion of the CROS complaints related to the amplified signal, IROS appears to be the preferable of the two. The exception involves cases requiring high gain so that CROS might be employed to reduce acoustic feedback.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

In three experiments, the predictability of the hearing aid gain actually used by clients was compared with that predicted by using data based upon hearing threshold level and data based upon most comfortable loudness level. At the frequencies tested, the mean difference between the predicted and obtained gain was smaller when based upon prediction from the hearing threshold level. It is concluded that from the standpoint of predicting user's gain, the hearing threshold level provides greater accuracy than does most comfortable loudness level.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Forty-five normal-hearing subjects were divided into three groups to determine the effects of listener sophistication on threshold estimates obtained with three commonly used tests for pseudohypacusis. A pure-tone Stenger test, speech Stenger test, and pure-tone delayed auditory feedback test were performed on each subject. The results indicate that increased sophistication levels allow subjects to simulate larger hearing losses on the two Stenger procedures. Sophistication level did not play a significant role in threshold determination with the delayed auditory feedback procedure, which was also found to be the closest indicator of true threshold.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Frequency response curves were obtained for a Radioear B-71 and a 8–72 bone vibrator with a revised Bruel and Kjaer model 4930 artificial mastoid. The curves for each vibrator were characterized by three resonant peaks which decreased in amplitude as frequency increased. The maximal output voltage variations of the artificial mastoid were ≥2 dB for each vibrator at all audiometric frequencies (±3%), except for the B-72 at 4000 Hz where the variation was 6.9 dB. Overall, the findings were interpreted to question the use of a ±3% frequency tolerance for the generation and calibration of reference bone conduction thresholds.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Acoustic reflex (AR) threshold and growth were measured in one ear for each of 20 normal-hearing individuals as pressure in the ear canal was varied between k120 mm of H2O. These same parameters were studied in 10 of the subjects after disruption of the probe seal. Activating stimuli for AR threshold measures were 500, 1000, 2000, and 4000 Hz tones and broadband noise. The AR growth function was generated by a 500 Hz tone. As ear canal pressure was increased or decreased relative to the point of maximal compliance, systematic increases in AR threshold were observed for all activating stimuli. These mean pressure effects were relatively small (4 to 8 dB) and were essentially independent of stimulus composition. The ear canal pressure variations had no effect on the relative difference between tone and broadband noise AR thresholds. Absence of an airtight seal had a negligible effect on AR threshold. Growth of the AR was significantly altered by application of a relatively mild positive or negative canal pressure. Absence of a probe seal which had no effect on AR threshold was found to significantly reduce magnitude of the AR. These findings indicate that caution should be exercised during the measurement of AR growth to ensure both proper maintenance of desired canal pressure and canal-probe coupling.

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1982

数据来源: OVID