Biomedical subjects

Larry E Humes

Publications and source records attributed to Larry E Humes.

12 recordsLinked to original sources

PubMed2005

Measures of working memory, sequence learning, and speech recognition in the elderly.

This study describes the measurement of 2 cognitive functions, working-memory capacity and sequence learning, in 2 groups of listeners: young adults with normal hearing and elderly adults with impaired hearing. The measurement of these 2 cognitive abilities with a unique, nonverbal technique capable of auditory, visual, and auditory-visual stimulation, patterned after the Simon memory game, is described. The use of simple, easily understood items in the test sequences enabled the measurement of these cognitive abilities in older listeners with no apparent impact of age-related hearing loss on the cognitive measures. Age-related cognitive deficits were observed for all 3 modes of stimulation and in both working-memory capacity and sequence-learning ability. The age-related deficits appeared to be greatest, however, for the sequence-learning task. Although it was hypothesized that there might be an association between an individual's performance on these cognitive tasks and his or her performance on various measures of speech recognition, such an association generally was not observed.

Adult↗

PubMed2005

Do 'auditory processing' tests measure auditory processing in the elderly?

OBJECTIVE: To examine the associations between measures of auditory processing and measures of auditory or cognitive function in elderly listeners with impaired hearing. DESIGN: Multiple measures of auditory processing, auditory function, and cognitive function were obtained and linear, multiple-regression analyses were conducted to examine the relations between these sets of variables. In particular, four measures of auditory processing were obtained from each of 213 elderly participants. Measures of auditory processing included duration discrimination for a 1000-Hz pure tone, temporal-order discrimination for mid-frequency pure tones, dichotic syllable identification, and recognition of 45% time-compressed monosyllables. Each participant also completed additional measures of auditory function, including pure-tone thresholds, auditory brain stem responses for each ear and at two presentation rates (11.1 and 71.1 clicks per second), and performance-intensity functions for monosyllabic words (PI-PB rollover). Finally, three measures of cognitive function, all from the Wechsler Adult Intelligence Scale-Revised, were obtained from the 213 participants. RESULTS: For three of the four measures of auditory processing examined in this study (duration discrimination, temporal-order discrimination, and dichotic CV identification), a measure of cognitive function (IQ) and age were the two primary predictors of individual differences in performance. For these three measures of auditory processing, 11 to 14% of the total variance could be accounted for by the predictor variables. For the remaining measure of auditory processing (recognition of time-compressed monosyllables), 56% of the total variance could be accounted for by a set of four predictor variables, but most of this variance (54% of the total variance) was associated with individual differences in hearing loss. When hearing loss was removed as a predictor for this measure of auditory processing, 14% of the total variance was explained by four variables: age, IQ, and two measures derived from auditory brain stem response wave-V latency. CONCLUSIONS: Performance on the battery of auditory processing measures by elderly hearing-impaired listeners was systematically related to individual differences in cognitive function rather than auditory function, especially for stimuli not affected by peripheral hearing loss. However, much of the variance in auditory processing performance remained unaccounted for by any of the predictor variables examined in this study.

Aged↗

PubMed2004

A comparison of single-channel linear amplification and two-channel wide-dynamic-range-compression amplification by means of an independent-group design.

The present study used an independent-group design to compare the benefits provided by binaural, single-channel, linear, full-shell in-the-ear hearing aids and binaural, 2-channel, wide-dynamic-range-compression in-the-canal hearing aids in groups of older hearing aid wearers. Hearing aid outcome measures were obtained at both 1-month (n = 53) and 6-month (n = 34) postfit intervals with each device. Outcome measures included multiple measures of speech-recognition performance and self-report measures of hearing aid benefit, satisfaction, and usage. Aided sound-quality measurements were also obtained. Although both devices provided significant benefits to the wearers, there were no significant differences in the benefits provided by either device at the 1-month or 6-month postfit intervals.

Aged↗

PubMed2004

Predictability of speech-in-noise performance from real ear measures of directional hearing AIDS.

OBJECTIVE: Inability to understand speech in noise has been cited repeatedly as the principal complaint of hearing aid users. While data exist documenting the benefit provided by hearing aids with directional microphones when listening to speech in noise, little work has been done to develop a standard clinical protocol for fitting these hearing aids. Our goal was to evaluate a clinical measure of the acoustic directivity of a directional hearing aid, including its association with a test of speech perception in noise. DESIGN: The performance of two commercially available directional behind-the-ear (BTE) hearing aids was evaluated using the Hearing in Noise Test (HINT) and the Real Ear Aided Response (REAR) on 24 adult participants with symmetric, mild to moderately severe, sensorineural hearing loss. The HINT was conducted with the speech signal presented from 0 degrees and the noise from 180 degrees and either 135 degrees or 225 degrees, depending on the ear tested. REAR was measured at the above three angles using swept pure tones, and these measures were used to compute in situ directivity for each subject and hearing aid. CONCLUSIONS: Directional benefit for the HINT was greatest when noise was presented from the azimuth of the published polar diagram null of a given hearing aid in its directional mode (180 or 135/225 degrees). The only significant correlation between HINT and REAR results, however, was found when the noise source was at 180 degrees. These results confirm the validity of using real ear measures as a way to assess directionality in situ, but also indicate the complexity of predicting perceptual benefit from them. These data suggest that factors beyond acoustic directionality may contribute to improvement in speech perception in noise when such improvements are found.

Adult↗

PubMed2003

An examination of changes in hearing-aid performance and benefit in the elderly over a 3-year period of hearing-aid use.

This brief report describes the changes in hearing-aid performance and benefit in 9 elderly hearing-aid wearers over a 3-year period following the hearing-aid fitting. Objective measures of hearing-aid performance included three measures of speech recognition: (a) the Nonsense Syllable Test (NST) presented at 65 dB SPL and a +8 dB signal-to-noise ratio (SNR), (b) the Connected Speech Test (CST) presented at 50 dB SPL in quiet, and (c) the CST presented at 65 dB SPL and a +8 dB SNR. Subjective, self-report measures of hearing-aid benefit included the Hearing Aid Performance Inventory (HAPI; B. E. Walden, M. E. Demorest, & E. L. Helper, 1984) and the Hearing Handicap Inventory for the Elderly (HHIE; I. Ventry & B. Weinstein, 1982). Performance and benefit measures were obtained at postfit intervals of 1 month, 6 months, 1 year, 2 years, and 3 years using a standardized measurement protocol. Individual data were evaluated using 95% critical differences established previously for each benefit measure and applied around the scores observed at the 1-month postfit interval. Little evidence was seen for systematic improvement in aided performance or benefit, consistent with that expected from acclimatization, in any participant or for any measure of benefit.

Aged↗

PubMed2003

Reliability and validity of judgments of sound quality in elderly hearing aid wearers.

OBJECTIVE: The aim of the present study was to evaluate a particular sound-quality rating procedure, referred to here as the Judgments of Sound Quality (JSQ) test, for potential use as an outcome measure with elderly hearing aid wearers. The validity and reliability of the JSQ as an outcome measure were determined for unaided and aided listening conditions. DESIGN: A repeated-measures design was employed with two primary independent variables, each with two values: 1) aided condition (aided versus unaided listening); and 2) trial (test versus retest). Sixteen elderly, hearing-impaired hearing aid users participated in the study. The participants provided ratings on eight dimensions of sound quality (softness, brightness, clarity, fullness, nearness, loudness, spaciousness, and total impression) under four stimulus conditions (speech at 65 dB SPL with a +8 dB signal-to-noise ratio, speech at 65 dB SPL in quiet, music at 90 dB SPL, and music at 75 dB SPL). Test and retest ratings were obtained in both unaided and aided conditions. RESULTS: No significant differences were found between median test and retest scores on the JSQ. The median ratings for each sound-quality dimension were found to have moderate test-retest reliability, with test-retest correlations (r) ranging from 0.20 to 0.73 (median r value = 0.58) for the unaided listening condition, and from 0.23 to 0.85 (median r value = 0.51) for the aided listening condition. Test validity was established through significant differences in JSQ ratings for various stimulus pairs (e.g., speech in quiet versus speech in noise). In addition, significant differences were observed between unaided and aided ratings for the dimensions of clarity, nearness, loudness, and total impression with aided JSQ ratings approaching normative "ideal" values established previously. CONCLUSIONS: The JSQ appears to be a potentially useful measure of hearing aid outcome, especially when using group data to document the benefits of amplification. Additional efforts should be directed at improving the reliability of the JSQ, however, before application to hearing aid wearers on an individual basis.

Aged↗

PubMed2003

Modeling and predicting hearing aid outcome.

Following a brief tutorial on the application of factor analysis to hearing aid outcome measures, three studies of hearing aid outcome measures in elderly adults are presented and analyzed. Two of the studies were completed at Indiana University (IU-1 and IU-2), and one was a collaborative multisite study by the Veterans Administration and the National Institute of Deafness and other Communication Disorders (NIDCD/VA). IU-1 measured hearing aid outcome in 173 elderly wearers of single-channel, linear, in-the-ear hearing aids with output-limiting compression, whereas IU-2 obtained the same extensive set of outcome measures from 53 elderly wearers of two-channel, wide-dynamic-range compression, in-the-canal hearing aids. In the NIDCD/VA study, 333 to 338 participants wore three single-channel circuits in succession, with each circuit housed within an in-the-ear shell. The three circuits included in that study and in this analysis were: (1) linear with peak clipping, (2) linear with output-limiting compression, and (3) single-channel, wide-dynamic-range compression. Evaluation of the many outcome measures completed in each study using principal components factor analysis revealed that from three (both IU studies) to five (NIDCD/VA study) principal components captured the individual differences in hearing aid outcome. This was independent of hearing aid type (in-the-ear or in-the-canal) and circuitry. Subsequent multiple regression analyses of individual differences in performance along each dimension of hearing aid outcome revealed that these individual differences could be accounted for reasonably well by various prefit variables for some dimensions of outcome, but not others. In general, measures of speech recognition performance were well accounted for by prefit measures, with the best predictors being hearing loss, cognitive performance, and age. Measures of hearing aid usage were less well accounted for by prefit measures, with the most accurate predictor of current hearing aid use being prior hearing aid use. The outcome dimension accounted for most poorly was that associated with hearing aid satisfaction, with subjective measures of aided sound quality being the best predictor of performance along this dimension of hearing aid outcome. Additional multicenter, large-scale studies are needed to develop more complete models of hearing aid outcome and to identify the variables that influence various aspects of hearing aid outcome. It is only through this additional research that it will be possible to optimize outcome for hearing aid wearers.

Journal Article↗

PubMed2003

Examination of differences between successful and unsuccessful elderly hearing aid candidates matched for age, hearing loss and gender.

This study examined group differences on a variety of measures for three groups of elderly hearing aid candidates matched for gender, age and hearing loss. These three groups were: (1) 26 candidates who declined amplification (non-adherents); (2) 24 individuals who purchased hearing aids, but subsequently returned them (rejected HA); and (3) 26 who purchased hearing aids and continued to use their hearing aids for at least the first 6 months following delivery (accepted HA). Following demonstration of adequate reliability for these measures, using the non-adherents as the test retest study sample, group differences were examined for each pre-fit measure. The group of non-adherents who declined amplification differed from the two groups who purchased hearing aids on their scores for the Hearing Handicap Inventory for the Elderly (HHIE) and for several scales of the Communication Profile for the Hearing Impaired (CPHI) that assessed the individual's personal adjustment to hearing impairment. These findings were generally confirmed for the individual data, with the use of discriminant analysis. For the two groups who tried hearing aids, there were no group differences between those who retained them and those who did not. Discriminant analysis, however, indicated that those in the group who retained their (linear) hearing aids tended to have better finger dexterity and higher loudness discomfort levels than those who did not.

Adaptation, Physiological↗

PubMed2002

Changes in hearing-aid benefit following 1 or 2 years of hearing-aid use by older adults.

This study reports the results of a large number of hearing-aid benefit measures obtained from 134 elderly hearing-aid wearers during the first year of hearing-aid usage. Benefit measures were obtained after 1 month, 6 months, and 1 year of hearing-aid use by all participants. In addition, follow-up measurements of hearing-aid benefit were performed on 49 of these same hearing-aid wearers following 2 years of hearing-aid use. All participants in this study were fit binaurally with identical full-concha in-the-ear (ITE) hearing aids that used linear Class-D amplifiers with output-limiting compression. Benefit measures included several objective tests of speech recognition, as well as the subjective self-report scales of the Hearing Aid Performance Inventory (HAPI; B. E. Walden, M. E. Demorest, & E. L. Hepler) and the Hearing Handicap Inventory for the Elderly (HHIE; I. Ventry & B. Weinstein, 1982). Although group means changed only slightly over time for all of the benefit measures, significant differences were observed for some of the benefit measures, especially among the subjective, self-report measures of benefit. In almost all of the cases exhibiting significant changes, performance was significantly worse (less benefit) at both the 6-month and 1-year post-fit interval compared to the measurements at 1 month post-fit. In general, the individual data from the 134 participants who were represented in the 1-year data set were consistent with the trends in the group data described above. Regarding longer term changes in benefit following 2 years of hearing-aid use, minimal changes were again observed. In all, there was little evidence for acclimatization of hearing-aid benefit in this study in either the group or the individual data.

Aged↗

PubMed2002

A comparison of two measures of hearing aid satisfaction in a group of elderly hearing aid wearers.

OBJECTIVE: The objective of this study was to compare the results of two measures of hearing aid satisfaction, an indirect measure (Satisfaction with Amplification in Daily Living, SADL; Cox & Alexander, 1999) and a direct measure (an expanded version of the MarkeTrak-IV survey; Kochkin, 1996), in a group of elderly hearing aid wearers. DESIGN: A total of 43 elderly hearing aid wearers completed both satisfaction measures (order counterbalanced across wearers) after 1 mo of wearing 2-channel wide dynamic range compression (WDRC) in-the-canal (ITC) hearing aids. A correlational research design was employed. RESULTS: The elderly hearing aid wearers in this study yielded results on each measure of hearing aid satisfaction that were generally consistent with those found previously in larger groups of similar samples. The correlation between each measure of satisfaction (r = 0.75) was positive, moderately strong, and significant (p < 0.01) for the global scores of the SADL and MarkeTrak-IV scales. CONCLUSIONS: Although different approaches to the measurement of satisfaction were followed in the development of the SADL (indirect approach) and the MarkeTrak-IV (direct measurement) scales, similar results were obtained with each scale. The 15-item SADL instrument, however, is much shorter than the MarkeTrak-IV instrument and, as a result, is more efficient to administer clinically.

Acoustic Stimulation↗

PubMed2002

Longitudinal changes in hearing aid satisfaction and usage in the elderly over a period of one or two years after hearing aid delivery.

OBJECTIVE: The objective of this study was to measure hearing aid satisfaction and usage for extended periods of time, up to 2 yr after hearing aid delivery, to determine whether longitudinal changes occur in the elderly for these outcome measures. DESIGN: A longitudinal study of hearing aid satisfaction and usage was performed in a group comprised of 134 elderly hearing aid wearers with these outcome measures obtained at 1, 6, and 12 mo postfit. A total of 49 of the original 134 elderly returned 2 yr after hearing aid delivery to complete the satisfaction and usage measures again. Multiple self-report measures of hearing aid satisfaction and hearing aid usage were obtained at each follow-up session. RESULTS: Most between-interval comparisons of the various measures of satisfaction and usage failed to reveal significant changes over time. However, some significant changes were observed in both satisfaction and usage. When such changes occurred, they were always in a direction that suggested a decrease in satisfaction or usage over time. Correlations across various postfit interval pairs were found to be positive, statistically significant, and moderate to strong in strength for all measures of satisfaction and usage. CONCLUSIONS: Although there were slight declines in hearing aid usage and satisfaction over time, measures of hearing aid satisfaction obtained at 1 mo postfit and of hearing aid usage obtained at 6 mo postfit are generally stable for up to 2 yr after hearing aid delivery.

Aged↗

PubMed2002

Factors underlying the speech-recognition performance of elderly hearing-aid wearers.

This paper reports the aided and unaided speech-recognition scores from a group of 171 elderly hearing-aid wearers. All hearing-aid wearers were fit with identical instruments (linear Class-D amplifiers with output-limiting compression) and evaluated with a standard protocol. In addition to including multiple measures of speech recognition, an extensive set of physiological and perceptual measures of auditory function, as well as general measures of cognitive function, were completed prior to the hearing-aid fitting. Comparison of the results from this study to available norms suggested that this group of participants was fairly typical or representative for their hearing loss and age. Approaches to the prediction of general speech-recognition performance that were examined included methods based on an acoustical index, the Speech Intelligibility Index (SII), and others based on linear-regression statistical analysis. The latter approach proved to be the most successful, accounting for about two-thirds of the variance in speech-recognition performance, with the primary predictive factors being measures of hearing loss and cognitive function.

Aged↗