Neural representation of dynamic frequency is degraded in older adults.
Hear Res
; 323: 91-8, 2015 May.
Article
em En
| MEDLINE
| ID: mdl-25724819
ABSTRACT
Older adults, even with clinically normal hearing sensitivity, often report difficulty understanding speech in the presence of background noise. Part of this difficulty may be related to age-related degradations in the neural representation of speech sounds, such as formant transitions. Frequency-following responses (FFRs), which are dependent on phase-locked neural activity, were elicited using sounds consisting of linear frequency sweeps, which may be viewed as simple models of formant transitions. Eighteen adults (ten younger, 22-24 years old, and nine older, 51-67 years old) were tested. FFRs were elicited by tonal sweeps in six conditions. Two directions of frequency change, rising or falling, were used for each of three rates of frequency change. Stimulus-to-response cross correlations revealed that older adults had significantly poorer representation of the tonal sweeps, and that FFRs became poorer for faster rates of change. An additional FFR signal-to-noise ratio analysis based on time windows revealed that across the FFR waveforms and rates of frequency change, older adults had smaller (poorer) signal-to-noise ratios. These results indicate that older adults, even with clinically-normal hearing sensitivity, have degraded phase-locked neural representations of dynamic frequency.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Percepção da Altura Sonora
/
Vias Auditivas
/
Percepção da Fala
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Envelhecimento
Tipo de estudo:
Prognostic_studies
Limite:
Adult
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Aged
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Humans
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Middle aged
Idioma:
En
Revista:
Hear Res
Ano de publicação:
2015
Tipo de documento:
Article