Processing interaural cues in sound segregation by young and middle-aged brains

Ilse Wambacq, Janet Koehnke, Joan Besing, Laurie L. Romei, Ann Marie DePierro, David Cooper

Research output: Contribution to journalArticleResearchpeer-review

11 Citations (Scopus)

Abstract

Background: When listening to one speaker while another conversation is occurring simultaneously, we separate the competing sounds by processing physical cues such as common onset time, intensity, frequency harmonicity, and spatial location of the sound sources. Spatial location is determined in large part by differences in arrival of a sound at one ear versus the other ear, otherwise known as interaural time difference (ITD) or interaural phase difference (IPD). There is ample anecdotal evidence that middleaged adults experience greater difficulty listening to speech in noise, even when their audiological evaluation does not reveal abnormal results. Furthermore, it has been shown that the frequency range for IPD processing is reduced in middle-aged adults compared to young adults, even though morphological changes in the auditory evoked potential (AEP) response were only observed in older adults. Purpose: The purpose of the current study was to examine early aging effects (<60 years) on IPD processing in concurrent sound segregation. Research Design: We examined the change AEP evoked by detection of a mistuned and/or phaseshifted second harmonic during the last 1500 msec of a 3000 msec amplitude-modulated harmonic complex. A passive listening paradigm was used. Study Sample: Ten young (21-35 years) and 11 middle-aged (48-57 years) adults with normal hearing were included in the study. Data Collection and Analysis: Scalp electroencephalographic activity was recorded from 63 electrodes. A temporospatial principal component analysis was conducted. Spatial factor scores of individual spatial factors were the dependent variable in separatemixed-design ANOVAs for each temporal factor of interest. Stimulus type was the within-subject independent variable, and age group was the between-subject independent variable. Results: Results indicated a delay in the upward P2 slope and the P2 peak latency to a sudden phase shift in the second harmonic of a harmonic complex in middle-aged adults compared to young adults. This AEP difference increased as mistuning (as a second grouping cue) decreased and remained evident when the IPD was the only grouping cue. Conclusions: We conclude that our findings reflect neurophysiologic differences between young and middle-aged adults for IPD processing in concurrent sound segregation.

Original languageEnglish
Pages (from-to)453-458
Number of pages6
JournalJournal of the American Academy of Audiology
Volume20
Issue number7
DOIs
StatePublished - 27 Nov 2009

Fingerprint

Auditory Evoked Potentials
Cues
Brain
Ear
Young Adult
Principal Component Analysis
Scalp
Hearing
Noise
Analysis of Variance
Electrodes
Research Design
Age Groups

Keywords

  • Auditory evoked potentials
  • Concurrent sound segregation
  • Dichotic grouping cues

Cite this

@article{e198c5b2307b4f54b70ee049d37f1802,
title = "Processing interaural cues in sound segregation by young and middle-aged brains",
abstract = "Background: When listening to one speaker while another conversation is occurring simultaneously, we separate the competing sounds by processing physical cues such as common onset time, intensity, frequency harmonicity, and spatial location of the sound sources. Spatial location is determined in large part by differences in arrival of a sound at one ear versus the other ear, otherwise known as interaural time difference (ITD) or interaural phase difference (IPD). There is ample anecdotal evidence that middleaged adults experience greater difficulty listening to speech in noise, even when their audiological evaluation does not reveal abnormal results. Furthermore, it has been shown that the frequency range for IPD processing is reduced in middle-aged adults compared to young adults, even though morphological changes in the auditory evoked potential (AEP) response were only observed in older adults. Purpose: The purpose of the current study was to examine early aging effects (<60 years) on IPD processing in concurrent sound segregation. Research Design: We examined the change AEP evoked by detection of a mistuned and/or phaseshifted second harmonic during the last 1500 msec of a 3000 msec amplitude-modulated harmonic complex. A passive listening paradigm was used. Study Sample: Ten young (21-35 years) and 11 middle-aged (48-57 years) adults with normal hearing were included in the study. Data Collection and Analysis: Scalp electroencephalographic activity was recorded from 63 electrodes. A temporospatial principal component analysis was conducted. Spatial factor scores of individual spatial factors were the dependent variable in separatemixed-design ANOVAs for each temporal factor of interest. Stimulus type was the within-subject independent variable, and age group was the between-subject independent variable. Results: Results indicated a delay in the upward P2 slope and the P2 peak latency to a sudden phase shift in the second harmonic of a harmonic complex in middle-aged adults compared to young adults. This AEP difference increased as mistuning (as a second grouping cue) decreased and remained evident when the IPD was the only grouping cue. Conclusions: We conclude that our findings reflect neurophysiologic differences between young and middle-aged adults for IPD processing in concurrent sound segregation.",
keywords = "Auditory evoked potentials, Concurrent sound segregation, Dichotic grouping cues",
author = "Ilse Wambacq and Janet Koehnke and Joan Besing and Romei, {Laurie L.} and DePierro, {Ann Marie} and David Cooper",
year = "2009",
month = "11",
day = "27",
doi = "10.3766/jaaa.20.7.6",
language = "English",
volume = "20",
pages = "453--458",
journal = "Journal of the American Academy of Audiology",
issn = "1050-0545",
publisher = "American Academy of Audiology",
number = "7",

}

Processing interaural cues in sound segregation by young and middle-aged brains. / Wambacq, Ilse; Koehnke, Janet; Besing, Joan; Romei, Laurie L.; DePierro, Ann Marie; Cooper, David.

In: Journal of the American Academy of Audiology, Vol. 20, No. 7, 27.11.2009, p. 453-458.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Processing interaural cues in sound segregation by young and middle-aged brains

AU - Wambacq, Ilse

AU - Koehnke, Janet

AU - Besing, Joan

AU - Romei, Laurie L.

AU - DePierro, Ann Marie

AU - Cooper, David

PY - 2009/11/27

Y1 - 2009/11/27

N2 - Background: When listening to one speaker while another conversation is occurring simultaneously, we separate the competing sounds by processing physical cues such as common onset time, intensity, frequency harmonicity, and spatial location of the sound sources. Spatial location is determined in large part by differences in arrival of a sound at one ear versus the other ear, otherwise known as interaural time difference (ITD) or interaural phase difference (IPD). There is ample anecdotal evidence that middleaged adults experience greater difficulty listening to speech in noise, even when their audiological evaluation does not reveal abnormal results. Furthermore, it has been shown that the frequency range for IPD processing is reduced in middle-aged adults compared to young adults, even though morphological changes in the auditory evoked potential (AEP) response were only observed in older adults. Purpose: The purpose of the current study was to examine early aging effects (<60 years) on IPD processing in concurrent sound segregation. Research Design: We examined the change AEP evoked by detection of a mistuned and/or phaseshifted second harmonic during the last 1500 msec of a 3000 msec amplitude-modulated harmonic complex. A passive listening paradigm was used. Study Sample: Ten young (21-35 years) and 11 middle-aged (48-57 years) adults with normal hearing were included in the study. Data Collection and Analysis: Scalp electroencephalographic activity was recorded from 63 electrodes. A temporospatial principal component analysis was conducted. Spatial factor scores of individual spatial factors were the dependent variable in separatemixed-design ANOVAs for each temporal factor of interest. Stimulus type was the within-subject independent variable, and age group was the between-subject independent variable. Results: Results indicated a delay in the upward P2 slope and the P2 peak latency to a sudden phase shift in the second harmonic of a harmonic complex in middle-aged adults compared to young adults. This AEP difference increased as mistuning (as a second grouping cue) decreased and remained evident when the IPD was the only grouping cue. Conclusions: We conclude that our findings reflect neurophysiologic differences between young and middle-aged adults for IPD processing in concurrent sound segregation.

AB - Background: When listening to one speaker while another conversation is occurring simultaneously, we separate the competing sounds by processing physical cues such as common onset time, intensity, frequency harmonicity, and spatial location of the sound sources. Spatial location is determined in large part by differences in arrival of a sound at one ear versus the other ear, otherwise known as interaural time difference (ITD) or interaural phase difference (IPD). There is ample anecdotal evidence that middleaged adults experience greater difficulty listening to speech in noise, even when their audiological evaluation does not reveal abnormal results. Furthermore, it has been shown that the frequency range for IPD processing is reduced in middle-aged adults compared to young adults, even though morphological changes in the auditory evoked potential (AEP) response were only observed in older adults. Purpose: The purpose of the current study was to examine early aging effects (<60 years) on IPD processing in concurrent sound segregation. Research Design: We examined the change AEP evoked by detection of a mistuned and/or phaseshifted second harmonic during the last 1500 msec of a 3000 msec amplitude-modulated harmonic complex. A passive listening paradigm was used. Study Sample: Ten young (21-35 years) and 11 middle-aged (48-57 years) adults with normal hearing were included in the study. Data Collection and Analysis: Scalp electroencephalographic activity was recorded from 63 electrodes. A temporospatial principal component analysis was conducted. Spatial factor scores of individual spatial factors were the dependent variable in separatemixed-design ANOVAs for each temporal factor of interest. Stimulus type was the within-subject independent variable, and age group was the between-subject independent variable. Results: Results indicated a delay in the upward P2 slope and the P2 peak latency to a sudden phase shift in the second harmonic of a harmonic complex in middle-aged adults compared to young adults. This AEP difference increased as mistuning (as a second grouping cue) decreased and remained evident when the IPD was the only grouping cue. Conclusions: We conclude that our findings reflect neurophysiologic differences between young and middle-aged adults for IPD processing in concurrent sound segregation.

KW - Auditory evoked potentials

KW - Concurrent sound segregation

KW - Dichotic grouping cues

UR - http://www.scopus.com/inward/record.url?scp=70450212904&partnerID=8YFLogxK

U2 - 10.3766/jaaa.20.7.6

DO - 10.3766/jaaa.20.7.6

M3 - Article

VL - 20

SP - 453

EP - 458

JO - Journal of the American Academy of Audiology

JF - Journal of the American Academy of Audiology

SN - 1050-0545

IS - 7

ER -