Rose Chmiel

Effects of age and gender on dichotic sentence identification.

There is converging evidence that aging causes a progressive decline in the central processing of speech and that this decline is greater for left-ear than for right-ear input. In the present paper we investigated, by means of a dichotic sentence identification paradigm, some parameters of the “left ear effect.” We analyzed the clinical records of 366 individuals, 203 males and 163 females, to whom the Dichotic Sentence Identification (DSI) Test had been administered as part of routine audiometric assessment. Subjects ranged in age from B to 91 yr. The DSI test was always carried out in two modes: free report (FR) and directed report (DR). In the FR mode the subject reported what was heard in both ears. In the DR mode the subject reported only what was heard in one precued ear. In half of the trials the right ear was precued, in the other half the left ear was precued. Findings confirm a progressively larger right-ear advantage, or left-ear deficit, with increasing age. We document this effect in both the FR and DR modes, then demonstrate that the effects cannot be attributed to interaural asymmetries in threshold sensitivity. Comparison of male and female data suggest a gender difference in the effect of age on the left-ear deficit. Males show a larger effect then females in both modes of test administration. Finally, we propose a model of dichotic listening performance that attempts to explain ear asymmetry as the linear combination of an auditory/ structural component and a task-related/cognitive component. We then show how these hypothetical components change with age in the present sample.

Hearing impairment in older adults: new concepts.

OBJECTIVE: To review present information about the epidemiology, etiologies, pathogenesis, evaluation, and quality of life aspects of hearing loss and to present an approach to rehabilitation for hearing loss in older adults.

Dichotic listening, event-related potentials, and interhemispheric transfer in the elderly

Objective To determine the basis for the large, age-related asymmetries in dichotic listening performance scores reported by Jerger et al. (1994). Design Behavioral and electrophysiologic responses to dichotic listening tasks in both verbal and nonverbal paradigms were obtained in four groups of subjects: young adults with normal hearing, elderly persons with presbyacusis, elderly persons with presbyacusis and marked dichotic deficits, and patients with lesions of the corpus callosum. Results In comparison with the young group the two elderly groups showed an increasing left-ear deficit on the verbal task, and an increasing right-ear deficit on the nonverbal paradigm. The pattern of results obtained in the elderly persons with marked dichotic deficits was similar to the pattern of results in the group with callosal lesions. Conclusions With age, there may be a significant loss of efficiency of interhemispheric transfer of auditory information through the corpus callosum. Such age-related deficit might have important implications for the effective use of binaural information by elderly persons.

Effect of sleep on the auditory steady state evoked potential.

The effects of both natural and sedated sleep on the auditory steady state evoked potential (SSEP) were evaluated in nine normal-hearing subjects. Both absolute amplitude and phase variability measures were obtained by Fourier analysis of successive samples of the averaged SSEP waveform. Amplitude decreased significantly in the sleeping state but phase variability was not substantially altered. Because it does not seem to be affected by sleep, phase variability of the SSEP is suggested as a potentially useful technique for predicting threshold sensitivity.

Comparison of Conventional Amplification and an Assistive Listening Device in Elderly Persons

Objective: To assess the impact of personal amplification systems on quality of life of elderly persons and to compare conventional hearing aid with assistive listening device. Design: Audiologic, neuropsychologic, and quality‐of‐life measures were prospectively administered to 180 elderly, hearing‐impaired persons before and after randomized 6 wk trials of four treatment conditions‐a no‐amplification condition and three different types of amplification: 1) conventional hearing aid, 2) assistive listening device, and 3) a combination of the two systems. All subjects volunteered to participate in a study comparing different amplification systems and were paid for their participation. Results: Both self‐perceived handicap and speech understanding were improved significantly by all three amplification systems. There were no significant group differences between new users and previous users of amplification in self‐assessed handicap after amplification use. Anecdotally, subjects preferred the sound quality of the assistive listening device, but an overwhelming majority (97.3%) still chose the conventional aid for use in daily living. Conclusions: Results affirm the significant impact of amplification on the quality of life of elderly persons. The strong preference for the conventional hearing aid in everyday use undoubtedly reflects the fact that elderly users usually are not willing to endure the difficulties associated with the use of remote‐microphone systems.

Prediction of dynamic range from stapedius reflex in cochlear implant patients.

Amplitude growth functions of the electrically elicited stapedius reflex were compared with behavioral estimates of dynamic range in seven patients using multielectrode cochlear implants. The range between threshold and saturation level of the amplitude growth function usually either encompassed or fell between the preferred and uncomfortable listening levels. Implications of these findings for the initial mapping of electrodes in young children are discussed.

Quality of life in children with cochlear implants.

The striking consistency of the relationship between the preimplantation maternal reports of externalizing behavior and the implant outcomes is underscored by the fact that measures of positive social behavior (eg, sociability, affiliation) are related to reliable implant use. More sociable children may have more opportunities to use the implant and may also experience more social reinforcement for engaging in efforts at communicating.

Rate and Filter Dependence of the Middle-Latency Response in Infants

Auditory evoked-potential activity in the 0 to 100-ms latency range was explored using wide-band filtering and a range of stimulus rates, in 8 babies ranging in age from 2 to 6 months. We observed both a stable early positive peak, in the 10 to 15-ms region, and a rate-dependent, positive peak at about 50 ms in all 8 babies. The latter response was best observed at rates of 1-2.5 stimuli/s and seldom observed at rates above 4/s. This peak may represent a developmentally early version of the Pa peak of the adult middle-latency response.

Quantifying improvement with amplification

We employed a nonparametric measure, the randomization test, to evaluate, statistically, a variety of speech understanding measures used to quantify the efficacy of different intervention strategies in five clinical patients. The flexibility of the approach was demonstrated by comparing monaural with binaural amplification, a conventional aid with an assistive listening device, and a cochlear implant alone versus a cochlear implant supplemented by visual cues. The randomization test allows statistical analysis of differences in performance at the level of the individual subject. This approach may be useful in addressing accountability when recommending a specific intervention strategy for a particular hearing impaired individual.

Speech tracking in the evaluation of a multichannel cochlear prosthesis

Individual speech tracking data were analyzed in relation to other variables in 11 adult users of the Nucleus multichannel cochlear implant. Patients were categorized according to postoperative speech tracking results. The resultant groups could also be differentiated on the basis of postoperative MAC scores, surgeons rating of overall success, and duration of deafness before implantation. The speech tracking paradigm appears to be a useful technique for the evaluation of performance with a cochlear prosthesis.