摘要:

Objective:To describe the psychological status of deaf children with hearing parents who were seeking a cochlear implant and to compare them with deaf children with hearing parents who were not seeking a cochlear implant.Design:A sample of children consecutively referred for a cochlear implant at the University of Iowa Hospitals and Clinics was contrasted on a number of standardized psychological measures with a cohort of children from Boys Town National Research Hospital, who had hearing impairments and whose families had not sought a cochlear implant.Results:Although the comparison group evidenced more externalizing and social problems than the implant group, the means of both groups fell well within the normal range. Similarly, although mothers of the implant group rated their child's home as characterized by more positive and supportive interactions than did mothers of the children in the comparison group, both group means were well within the average range. On measures of intelligence, the two groups also did not differ.Conclusion:Overall, the study indicated that children with hearing impairments and their families who were seeking cochlear implants are not significantly different from children with hearing impairments whose parents were not seeking a cochlear implant. The results provided no support for the notion that children with hearing impairments from families seeking a cochlear implants for their child evidence more behavioral deviance than children with hearing impairments whose parents have not sought an implant.

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Objective:To compare the performance of cochlear implant patients and normal-hearing subjects on a musical interval labeling task, and to determine whether information regarding musical interval size is available to cochlear implant patients under realistic everyday listening conditions.Design:Two Nucleus cochlear implant patients listened to musical intervals that consisted of systematic variations of electric pulse rate on single bipolar intracochlear electrode pairs, whereas normal-hearing listeners were presented with the acoustical analog of these stimuli. Subjects labeled the intonation quality of the stimulus intervals ("flat," "sharp," or "in tune"), relative to their memory for specific intervals abstracted from familiar melodies. The cochlear implant patients, in addition, performed this task with realistic acoustical musical stimuli.Results:The interval labeling behavior of cochlear implant subjects, at low pulse rates, was similar to that of normal-hearing subjects. Furthermore, pitch interval information does not appear to be available to cochlear implant subjects when they are listening to acoustical stimuli via their speech processors.Conclusions:Temporal information appears to be sufficient for the perception of musical pitch. Encoding strategies that are highly successful in restoring speech understanding do not necessarily provide information regarding melodic pitch interval size.

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Objective:Three digital signal processing algorithms named RangeEar, DynEar, and LinEar were compared with regard to user preference and performance when a wearable digital filterbank hearing aid was used. All three algorithms provided individual frequency shaping via a seven-band filterbank. Compression was used in a low-frequency (LF) and a high-frequency (HF) channel. RangeEar and DynEar used wide dynamic range syllabic compression in the LF channel, whereas LinEar used compression limiting. In the HF channel, RangeEar used a slow acting automatic volume control, whereas DynEar and LinEar used compression limiting. The subjects had access to a manual volume control when using the LinEar or DynEar options.Design:The study included 13 hearing aid users with symmetrical sensorineural losses. In a 1 mo long blind field test, the RangeEar algorithm was compared with the preferred algorithm from an earlier study, DynEar or LinEar. A data logger function was included for objective recording of the total time each algorithm was used and how the volume controls were used. The preference was based on the time used for each algorithm and from subjective statements. Threshold signal-to-noise ratio (S/N-threshold) for speech was tested, and sound quality ratings were obtained through a questionnaire.Results:Of the 13 subjects, six preferred the RangeEar fitting and another four preferred the DynEar fitting. Two subjects preferred the LinEar fitting and one had equal preference for RangeEar and LinEar. The results from the questionnaire showed that the preferred fittings were rated higher concerning overall impression of sound quality and clearness, whereas the S/N for the speech test did not show any differences. Preferences, where stated, could be predicted from auditory dynamic range measurements in the LF and HF frequency ranges. The mean dynamic range was broader for low and narrower for high frequencies for those who preferred the RangeEar or DynEar fitting as compared with those who preferred the LinEar fitting. The preference between RangeEar and DynEar was predicted by differences in the HF range, with the narrower dynamic range for the DynEar preference subjects.Conclusion:Most subjects preferred the option of having a wide dynamic range syllabic compressor in the LF channel and having the overall gain in the HF channel adjustable, either manually (DynEar) or automatically (RangeEar).

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Objective:This article presents the underlying rationale, normative data, and reliability data for a test of loudness perception (the Contour Test) that was devised for use in clinical hearing aid fitting. The Contour Test yields data describing the sound level required for each of seven categories of loudness ranging from very soft to uncomfortably loud.Design:Two experiments are described. Experiment 1 yielded norms for the test. The subjects were 23 male and 22 female normal-hearing listeners. Test stimuli included warble tones at six frequencies and broad band speech. Experiment 2 assessed the reliability of the test results. Ten hearing-impaired listeners responded to the test at two frequencies on two occasions separated by several days. Both experiments also evaluated the effect of using different stimulus increment sizes on the measured levels of loudness categories.Results:Based on the data from experiment 1, norms for each category of each stimulus are reported in terms of mean level and typical between-subject variation in responses. Data are provided in HA-1 2 cm3coupler levels as well as in hearing levels (dB HL). The shape of the loudness growth function for warble tones was somewhat different from that for speech. When data were expressed in HL, there were no differences in mean loudness category levels across warble tone test frequencies. Thus, test frequencies were combined and equations were generated to describe the upper and lower limits of typical normal performance for warble tone stimuli. These equations can be used to construct a template for clinical comparison of normative values to patient loudness growth curves. Experiment 2 provided information about the test-retest variability of data yielded by the Contour Test. Reliability appears to be similar to that of the few other category scaling tests described in the literature. Most test-retest differences were 6 dB or less. Although a moderate variation in test increment size did not significantly affect the loudness category levels for young normal-hearing listeners, levels corresponding to loudness categories were significantly higher when larger increments were used with elderly hearing-impaired listeners.Conclusions:Evidence from this and other research indicates that standardized measurement of loudness perception is an achievable goal for clinical practice. The Contour Test appears to offer a viable approach to clinical measurement of loudness perception: It has good patient acceptance and combines fairly rapid administration with acceptable reliability. Details of test procedures and scoring sheets for manual administration can be down-loaded from the Internet at www.ausp.memphis.edu/harl. However, it is important to keep in mind that the application of loudness perception data for narrowband stimuli (such as warble tones) to hearing aid prescription is complicated by the need to account for the effects of loudness summation across bandwidth. There is a need for additional research to establish an empirical link between clinically measured loudness perception and optimal amplification characteristics.

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Objective:To determine if measurement procedure effects occur for loudness perception data measured using a categorical rating scale.Design:Loudness data were obtained from 40 normal-hearing adult volunteers, using 30 levels of pure tones at four frequencies (500, 1000, 2000, and 4000 Hz), with judgments made on a 9-point categorical scale. Two presentation orders, random and sequential, were compared within subjects. Subjects were divided into two groups: one group heard only a single tone on every trial, whereas the other group was presented with a maximum level reference tone at the start of each trial.Results:A significant difference was found between loudness function exponents measured with the random and sequential presentation order of stimulus level. A significant difference was found between loudness function exponents measured when a high-level referent was presented at the start of each trial. The sequential presentation order was further subdivided into ascending and descending runs, and the loudness function exponents for each run were examined separately. The results showed a significant interaction between sequence (ascending versus descending) and group.Conclusions:For normal-hearing listeners, the procedure used to measure loudness has an effect on the loudness function exponent obtained. These results appear to be related to stimulus context effects. Loudness function exponents are smaller when the stimulus is preceded by a stimulus level greater than the level of the test tone. This occurred when a high-level referent was presented at the start of each trial or when the stimulus level from the previous trial was greater than the test level, as in a descending run. It seems likely that the difference between loudness function exponents obtained with a random and sequential presentation of level can be explained by the same phenomenon. The significance of these results for hearing aid fittings in which loudness normalization is the goal is discussed.

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Objective:To assess the relationship of loudness growth and the click-evoked auditory brain stem response (ABR) wave V latency-intensity function (LIF) in listeners with normal hearing or cochlear hearing loss. The effect of hearing loss configuration on the intensity functions was also examined.Design:Behavioral and electrophysiological intensity functions were obtained using click stimuli of comparable intensities in listeners with normal hearing (Group I;n= 10), and cochlear hearing loss of flat(Group II;n= 10) or sloping (Group III;n= 10) configurations. Individual intensity functions were obtained from measures of loudness growth using the psychophysical methods of absolute magnitude estimation and production of loudness (geometrically averaged to provide the measured loudness function), and from the wave V latency measures of the ABR.Results:Slope analyses for the behavioral and electrophysiological intensity functions were separately performed by group. The loudness growth functions for the groups with cochlear hearing loss approximated the normal function at high intensities, with overall slope values consistent with those reported from previous psychophysical research. The ABR wave V LIF for the group with a flat configuration of cochlear hearing loss approximated the normal function at high intensities, and was displaced parallel to the normal function for the group with sloping configuration. The relationship between the behavioral and electrophysiological intensity functions was examined at individual intensities across the range of the functions for each subject. A significant relationship was obtained between loudness and the ABR wave V LIFs for the groups with normal hearing and flat configuration of cochlear hearing loss; the association was not significant (p= 0.10) for the group with a sloping configuration of cochlear hearing loss.Conclusion:The results of this study established a relationship between loudness and the ABR wave V latency for listeners with normal hearing, and flat cochlear hearing loss. In listeners with a sloping configuration of cochlear hearing loss, the relationship was not significant. This suggests that the click-evoked ABR may be used to estimate loudness growth at least for individuals with normal hearing and those with a flat configuration of cochlear hearing loss. Predictive equations were derived to estimate loudness growth for these groups. The use of frequency-specific stimuli may provide more precise information on the nature of the relationship between loudness growth and the ABR wave V latency, particularly for listeners with sloping configurations of cochlear hearing loss.

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Objective:To evaluate, using receiver operation characteristic (ROC) curves, the performance of several statistical indicators in the objective detection of 80 Hz steady state auditory evoked responses.Design:Steady state auditory evoked responses elicited by amplitude modulated tones of 500 and 1000 Hz, were obtained in 16 normal adults. Recordings were made at intensities ranging from 80 to 30 dB SPL and without stimulation. Four statistics: coherence synchrony measure, circularT2, a new variant of HotellingT2(labeled HT2) and a test for hidden periodicity (F test) were calculated. The statistics were compared using ROC curves and bootstrapping techniques. Two outcome measures were considered: behavioral threshold prediction and averaging efficiency.Results:All indicators were highly accurate to detect a response (8 to 9 dB above mean behavioral threshold for the 1000 Hz and 14 to 16 dB for the 500 Hz carrier). Responses could be reliable detected after averaging about five individual epochs of long duration. No statistically significant differences were evidenced though in their capability to predict behavioral threshold or their averaging efficiency.Conclusions:Despite the more adequate statistical properties of some of these indicators no significant differences were found in their performance. Thus all of these indicators could be recommended for automatic detection of 80 Hz auditory steady state responses.

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The equivalence was determined for the W-22 and NU No. 6 lists recorded with the same carrier phrase and by the same speaker (Auditec compact disc). For presentation, the lists were interleaved to form lists of 100 words. In Experiment 1, the materials were presented in quiet (0 to 30 dB HL) and in 60 dB SPL speech-spectrum noise (35 to 65 dB HL) at 5 dB intervals to 24 subjects with normal hearing. In Experiment 2, the materials were presented at two levels 10 dB apart to 24 subjects with sensorineural hearing loss. Recognition performance was on average 4 to 8% better on NU No. 6 materials than on the W-22 materials, a difference that was significant for both subject groups. The 2 to 4 dB differences are within the 5 dB steps typically used clinically and are not considered of clinical significance.

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1997

数据来源: OVID