The Influence of Aging on Interaural Asymmetries in Middle Latency Response Amplitude.
Background: Auditory-evoked potentials (EPs) provide a more objective assessment of central auditory nervous system (CANS) dysfunction when compared to behavioral measures because they do not require a behavioral response (Anderson and Kraus, 2010). in this regard, the middle latency response (MLR)...
| Publicado en: | Journal of the American Academy of Audiology Vol. 25; no. 4; pp. 324 - 335 |
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| Autores principales: | , |
| Formato: | research tables/charts tracings Journal Article |
| Publicado: |
Thieme Medical Publishing Inc.
Apr2014
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=107872968&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 107872968 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 10500545 9OC jtl: Journal of the American Academy of Audiology issn: 10500545 maglogo: Y pubinfo: dt: Apr2014 vid: 25 iid: 4 pid: 2811 pub: Thieme Medical Publishing Inc. place: New York, New York artinfo: ui: 107872968 97558390 10.3766/jaaa.25.4.4 NLM25126680 107872968 ppf: 324 ppct: 11 formats: fmt: @attributes: type: P tig: atl: The Influence of Aging on Interaural Asymmetries in Middle Latency Response Amplitude. aug: au: Weihing, Jeffrey Musiek, Frank affil: University of Louisville, Department of Surgery, Division of Communicative Disorders, Louisville, KY sug: subj: Aging Physiology Evoked Potentials, Auditory Speech Perception Hearing Physiology Human Cross Sectional Studies Adult Middle Age Aged Aged, 80 and Over Experimental Studies Factor Analysis Waveforms Noise Male Female Adult: 19-44 years Middle Aged: 45-64 years Aged: 65+ years Aged, 80 & over Male Female ab: Background: Auditory-evoked potentials (EPs) provide a more objective assessment of central auditory nervous system (CANS) dysfunction when compared to behavioral measures because they do not require a behavioral response (Anderson and Kraus, 2010). in this regard, the middle latency response (MLR) has been considered an important component of CANS assessment (Jerger et al, 1988); however, its large within-group variability limits its usefulness (Musiek et al, 1999). It has been argued that performing intratest calculations on the MLR (e.g., difference in EP amplitude when stimulating the left ear versus the right ear) can reduce the within-group variability of the MLR and enhance its clinical usefulness (Musiek et al, 1999; Weihing et al, 2012). To date, it has not been investigated how well these MLR intratest measures reduce within-group variability in adults of various ages, nor has it been shown that these intratest measures are sensitive to aging-related changes in the CANS. Purpose: The two primary goals of the present study were (1) to determine if calculating an intratest MLR measure, the difference in MLR Na-Pa peak-to-peak amplitude on left versus right ear stimulation (i.e., 'ear effects'), will reduce within-group variability in adults of various ages; and (2) to determine if ear effect magnitude will change as a function of aging. Ear effects were measured in both quiet and in noise to determine if the addition of noise enhanced any age-related-effects. Research Design: A cross-sectional study was conducted. Study Sample: The researchers studied 30 adults ranging in age from 20-80 yr with hearing sensitivity of 25 dB HL or better at the octave frequencies from 500-2000 Hz, and no history of neurologic issues. Adults were assigned to one of three age groups based on their chronological age, which were young adults, middle-aged adults, and older adults. Data Collection and Analysis: MLRs were acquired using a Nicolet Spirit 2000 during a single laboratory visit. To determine if within-group variability decreased significantly with ear effects, variability for absolute amplitude measures was compared to ear effect variability using the Pitman f-test. To examine potential effects of background noise and aging, data were analyzed using a mixed-factorial analysis of variance with the within-subjects factor 'background noise' and the between-subjects factor 'age group.' Results: Within-group variability was significantly reduced by calculating ear effects for the youngest group only. Additionally, the oldest adults in the present sample showed significantly larger ear effects than younger and middle-aged adults. This effect did not appear to be a result of differences in peripheral hearing sensitivity. Finally, introducing noise into the paradigm did not influence the observed effects. Conclusions: Ear effects become larger in older adults possibly as a result of age-related changes in the subcortical and/or cortical generators of the MLR. Failure of the ear effect calculation to reduce within-group variability in the middle-aged and older adults suggests that interaural asymmetries in MLR amplitude become more variable across participants who are older than 50 yr. Information obtained from this measure may benefit the development of treatment plans for older adults with hearing difficulties. pubtype: Academic Journal doctype: research tables/charts tracings Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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