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Kaya E, Kotz SA, Henry MJ. A novel method for estimating properties of attentional oscillators reveals an age-related decline in flexibility. eLife 2024; 12:RP90735. [PMID: 38904659 PMCID: PMC11192533 DOI: 10.7554/elife.90735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/22/2024] Open
Abstract
Dynamic attending theory proposes that the ability to track temporal cues in the auditory environment is governed by entrainment, the synchronization between internal oscillations and regularities in external auditory signals. Here, we focused on two key properties of internal oscillators: their preferred rate, the default rate in the absence of any input; and their flexibility, how they adapt to changes in rhythmic context. We developed methods to estimate oscillator properties (Experiment 1) and compared the estimates across tasks and individuals (Experiment 2). Preferred rates, estimated as the stimulus rates with peak performance, showed a harmonic relationship across measurements and were correlated with individuals' spontaneous motor tempo. Estimates from motor tasks were slower than those from the perceptual task, and the degree of slowing was consistent for each individual. Task performance decreased with trial-to-trial changes in stimulus rate, and responses on individual trials were biased toward the preceding trial's stimulus properties. Flexibility, quantified as an individual's ability to adapt to faster-than-previous rates, decreased with age. These findings show domain-specific rate preferences for the assumed oscillatory system underlying rhythm perception and production, and that this system loses its ability to flexibly adapt to changes in the external rhythmic context during aging.
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Affiliation(s)
- Ece Kaya
- Max Planck Institute for Empirical AestheticsFrankfurtGermany
- Maastricht UniversityMaastrichtNetherlands
| | - Sonja A Kotz
- Maastricht UniversityMaastrichtNetherlands
- Max Planck Institute for Human Cognitive and Brain SciencesLeipzigGermany
| | - Molly J Henry
- Max Planck Institute for Empirical AestheticsFrankfurtGermany
- Toronto Metropolitan UniversityTorontoCanada
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2
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McClaskey CM. Neural hyperactivity and altered envelope encoding in the central auditory system: Changes with advanced age and hearing loss. Hear Res 2024; 442:108945. [PMID: 38154191 PMCID: PMC10942735 DOI: 10.1016/j.heares.2023.108945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 12/04/2023] [Accepted: 12/22/2023] [Indexed: 12/30/2023]
Abstract
Temporal modulations are ubiquitous features of sound signals that are important for auditory perception. The perception of temporal modulations, or temporal processing, is known to decline with aging and hearing loss and negatively impact auditory perception in general and speech recognition specifically. However, neurophysiological literature also provides evidence of exaggerated or enhanced encoding of specifically temporal envelopes in aging and hearing loss, which may arise from changes in inhibitory neurotransmission and neuronal hyperactivity. This review paper describes the physiological changes to the neural encoding of temporal envelopes that have been shown to occur with age and hearing loss and discusses the role of disinhibition and neural hyperactivity in contributing to these changes. Studies in both humans and animal models suggest that aging and hearing loss are associated with stronger neural representations of both periodic amplitude modulation envelopes and of naturalistic speech envelopes, but primarily for low-frequency modulations (<80 Hz). Although the frequency dependence of these results is generally taken as evidence of amplified envelope encoding at the cortex and impoverished encoding at the midbrain and brainstem, there is additional evidence to suggest that exaggerated envelope encoding may also occur subcortically, though only for envelopes with low modulation rates. A better understanding of how temporal envelope encoding is altered in aging and hearing loss, and the contexts in which neural responses are exaggerated/diminished, may aid in the development of interventions, assistive devices, and treatment strategies that work to ameliorate age- and hearing-loss-related auditory perceptual deficits.
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Affiliation(s)
- Carolyn M McClaskey
- Department of Otolaryngology - Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Ave, MSC 550, Charleston, SC 29425, United States.
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3
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Jelinek J, Johne M, Alam M, Krauss JK, Kral A, Schwabe K. Hearing loss in juvenile rats leads to excessive play fighting and hyperactivity, mild cognitive deficits and altered neuronal activity in the prefrontal cortex. CURRENT RESEARCH IN NEUROBIOLOGY 2024; 6:100124. [PMID: 38616957 PMCID: PMC11015060 DOI: 10.1016/j.crneur.2024.100124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 12/23/2023] [Accepted: 12/29/2023] [Indexed: 04/16/2024] Open
Abstract
Background In children, hearing loss has been associated with hyperactivity, disturbed social interaction, and risk of cognitive disturbances. Mechanistic explanations of these relations sometimes involve language. To investigate the effect of hearing loss on behavioral deficits in the absence of language, we tested the impact of hearing loss in juvenile rats on motor, social, and cognitive behavior and on physiology of prefrontal cortex. Methods Hearing loss was induced in juvenile (postnatal day 14) male Sprague-Dawley rats by intracochlear injection of neomycin under general anesthesia. Sham-operated and non-operated hearing rats served as controls. One week after surgery auditory brainstem response (ABR) measurements verified hearing loss or intact hearing in sham-operated and non-operated controls. All rats were then tested for locomotor activity (open field), coordination (Rotarod), and for social interaction during development in weeks 1, 2, 4, 8, 16, and 24 after surgery. From week 8 on, rats were trained and tested for spatial learning and memory (4-arm baited 8-arm radial maze test). In a final setting, neuronal activity was recorded in the medial prefrontal cortex (mPFC). Results In the open field deafened rats moved faster and covered more distance than sham-operated and non-operated controls from week 8 on (both p < 0.05). Deafened rats showed significantly more play fighting during development (p < 0.05), whereas other aspects of social interaction, such as following, were not affected. Learning of the radial maze test was not impaired in deafened rats (p > 0.05), but rats used less next-arm entries than other groups indicating impaired concept learning (p < 0.05). In the mPFC neuronal firing rate was reduced and enhanced irregular firing was observed. Moreover, oscillatory activity was altered, both within the mPFC and in coherence of mPFC with the somatosensory cortex (p < 0.05). Conclusions Hearing loss in juvenile rats leads to hyperactive behavior and pronounced play-fighting during development, suggesting a causal relationship between hearing loss and cognitive development. Altered neuronal activities in the mPFC after hearing loss support such effects on neuronal networks outside the central auditory system. This animal model provides evidence of developmental consequences of juvenile hearing loss on prefrontal cortex in absence of language as potential confounding factor.
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Affiliation(s)
- Jonas Jelinek
- Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Marie Johne
- Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
- Cluster of Excellence Hearing4all, German Research Foundation, Hannover, Germany
| | - Mesbah Alam
- Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Joachim K. Krauss
- Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Andrej Kral
- Cluster of Excellence Hearing4all, German Research Foundation, Hannover, Germany
- Institute of AudioNeuroTechnology, Hannover Medical School, Stadtfelddamm 34, 30625, Hanover, Germany
- Department of Experimental Otology of the ENT Clinics, Hannover Medical School, Stadtfelddamm 34, 30625, Hannover, Germany
| | - Kerstin Schwabe
- Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
- Cluster of Excellence Hearing4all, German Research Foundation, Hannover, Germany
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4
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Angenstein N. Asymmetries and hemispheric interaction in the auditory system of elderly people. FRONTIERS IN NEUROIMAGING 2024; 2:1320989. [PMID: 38235106 PMCID: PMC10791916 DOI: 10.3389/fnimg.2023.1320989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/24/2023] [Indexed: 01/19/2024]
Abstract
Age-related changes of asymmetries in the auditory system and decreasing efficiency of hemispheric interaction have been discussed for some time. This mini-review discusses recent neuroimaging studies on alterations in lateralization of cortical processing and structural changes concerning the division of labor and interaction between hemispheres during auditory processing in elderly people with the focus on people without severe hearing loss. Several changes of asymmetries in anatomy, function and neurotransmitter concentration were observed in auditory cortical areas of older compared to younger adults. It was shown that connections between left and right auditory cortex are reduced during aging. Functionally, aging seems to lead to a reduction in asymmetry of auditory processing. However, the results do not always point into the same direction. Furthermore, correlations between function, anatomy and behavior in the left and right hemisphere appear to differ between younger and older adults. The changes in auditory cortex asymmetries with aging might be due to compensation of declining processing capacities, but at the same time these mechanisms could impair the balanced division of labor between the two hemispheres that is required for the processing of complex auditory stimuli such as speech. Neuroimaging studies are essential to follow the slow changes with aging as in the beginning no behavioral effects might be visible due to compensation. Future studies should control well for peripheral hearing loss and cognitive decline. Furthermore, for the interpretability of results it is necessary to use specific tasks with well-controlled task difficulty.
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Affiliation(s)
- Nicole Angenstein
- Combinatorial NeuroImaging Core Facility, Leibniz Institute for Neurobiology, Magdeburg, Germany
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5
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Karunathilake IMD, Dunlap JL, Perera J, Presacco A, Decruy L, Anderson S, Kuchinsky SE, Simon JZ. Effects of aging on cortical representations of continuous speech. J Neurophysiol 2023; 129:1359-1377. [PMID: 37096924 PMCID: PMC10202479 DOI: 10.1152/jn.00356.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 04/04/2023] [Accepted: 04/20/2023] [Indexed: 04/26/2023] Open
Abstract
Understanding speech in a noisy environment is crucial in day-to-day interactions and yet becomes more challenging with age, even for healthy aging. Age-related changes in the neural mechanisms that enable speech-in-noise listening have been investigated previously; however, the extent to which age affects the timing and fidelity of encoding of target and interfering speech streams is not well understood. Using magnetoencephalography (MEG), we investigated how continuous speech is represented in auditory cortex in the presence of interfering speech in younger and older adults. Cortical representations were obtained from neural responses that time-locked to the speech envelopes with speech envelope reconstruction and temporal response functions (TRFs). TRFs showed three prominent peaks corresponding to auditory cortical processing stages: early (∼50 ms), middle (∼100 ms), and late (∼200 ms). Older adults showed exaggerated speech envelope representations compared with younger adults. Temporal analysis revealed both that the age-related exaggeration starts as early as ∼50 ms and that older adults needed a substantially longer integration time window to achieve their better reconstruction of the speech envelope. As expected, with increased speech masking envelope reconstruction for the attended talker decreased and all three TRF peaks were delayed, with aging contributing additionally to the reduction. Interestingly, for older adults the late peak was delayed, suggesting that this late peak may receive contributions from multiple sources. Together these results suggest that there are several mechanisms at play compensating for age-related temporal processing deficits at several stages but which are not able to fully reestablish unimpaired speech perception.NEW & NOTEWORTHY We observed age-related changes in cortical temporal processing of continuous speech that may be related to older adults' difficulty in understanding speech in noise. These changes occur in both timing and strength of the speech representations at different cortical processing stages and depend on both noise condition and selective attention. Critically, their dependence on noise condition changes dramatically among the early, middle, and late cortical processing stages, underscoring how aging differentially affects these stages.
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Affiliation(s)
- I M Dushyanthi Karunathilake
- Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland, United States
| | - Jason L Dunlap
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland, United States
| | - Janani Perera
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland, United States
| | - Alessandro Presacco
- Institute for Systems Research, University of Maryland, College Park, Maryland, United States
| | - Lien Decruy
- Institute for Systems Research, University of Maryland, College Park, Maryland, United States
| | - Samira Anderson
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland, United States
| | - Stefanie E Kuchinsky
- Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, Maryland, United States
| | - Jonathan Z Simon
- Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland, United States
- Institute for Systems Research, University of Maryland, College Park, Maryland, United States
- Department of Biology, University of Maryland, College Park, Maryland, United States
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6
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Herrmann B, Maess B, Johnsrude IS. Sustained responses and neural synchronization to amplitude and frequency modulation in sound change with age. Hear Res 2023; 428:108677. [PMID: 36580732 DOI: 10.1016/j.heares.2022.108677] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 12/09/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
Perception of speech requires sensitivity to features, such as amplitude and frequency modulations, that are often temporally regular. Previous work suggests age-related changes in neural responses to temporally regular features, but little work has focused on age differences for different types of modulations. We recorded magnetoencephalography in younger (21-33 years) and older adults (53-73 years) to investigate age differences in neural responses to slow (2-6 Hz sinusoidal and non-sinusoidal) modulations in amplitude, frequency, or combined amplitude and frequency. Audiometric pure-tone average thresholds were elevated in older compared to younger adults, indicating subclinical hearing impairment in the recruited older-adult sample. Neural responses to sound onset (independent of temporal modulations) were increased in magnitude in older compared to younger adults, suggesting hyperresponsivity and a loss of inhibition in the aged auditory system. Analyses of neural activity to modulations revealed greater neural synchronization with amplitude, frequency, and combined amplitude-frequency modulations for older compared to younger adults. This potentiated response generalized across different degrees of temporal regularity (sinusoidal and non-sinusoidal), although neural synchronization was generally lower for non-sinusoidal modulation. Despite greater synchronization, sustained neural activity was reduced in older compared to younger adults for sounds modulated both sinusoidally and non-sinusoidally in frequency. Our results suggest age differences in the sensitivity of the auditory system to features present in speech and other natural sounds.
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Affiliation(s)
- Björn Herrmann
- Rotman Research Institute, Baycrest, North York, ON M6A 2E1, Canada; Department of Psychology, University of Toronto, Toronto, ON M5S 1A1, Canada; Department of Psychology & Brain and Mind Institute, The University of Western Ontario, London, ON N6A 3K7, Canada.
| | - Burkhard Maess
- Max Planck Institute for Human Cognitive and Brain Sciences, Brain Networks Unit, Leipzig 04103, Germany
| | - Ingrid S Johnsrude
- Department of Psychology & Brain and Mind Institute, The University of Western Ontario, London, ON N6A 3K7, Canada; School of Communication Sciences & Disorders, The University of Western Ontario, London, ON N6A 5B7, Canada
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Mai G, Howell P. The possible role of early-stage phase-locked neural activities in speech-in-noise perception in human adults across age and hearing loss. Hear Res 2023; 427:108647. [PMID: 36436293 DOI: 10.1016/j.heares.2022.108647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 10/26/2022] [Accepted: 11/04/2022] [Indexed: 11/11/2022]
Abstract
Ageing affects auditory neural phase-locked activities which could increase the challenges experienced during speech-in-noise (SiN) perception by older adults. However, evidence for how ageing affects SiN perception through these phase-locked activities is still lacking. It is also unclear whether influences of ageing on phase-locked activities in response to different acoustic properties have similar or different mechanisms to affect SiN perception. The present study addressed these issues by measuring early-stage phase-locked encoding of speech under quiet and noisy backgrounds (speech-shaped noise (SSN) and multi-talker babbles) in adults across a wide age range (19-75 years old). Participants passively listened to a repeated vowel whilst the frequency-following response (FFR) to fundamental frequency that has primary subcortical sources and cortical phase-locked response to slowly-fluctuating acoustic envelopes were recorded. We studied how these activities are affected by age and age-related hearing loss and how they are related to SiN performances (word recognition in sentences in noise). First, we found that the effects of age and hearing loss differ for the FFR and slow-envelope phase-locking. FFR was significantly decreased with age and high-frequency (≥ 2 kHz) hearing loss but increased with low-frequency (< 2 kHz) hearing loss, whilst the slow-envelope phase-locking was significantly increased with age and hearing loss across frequencies. Second, potential relationships between the types of phase-locked activities and SiN perception performances were also different. We found that the FFR and slow-envelope phase-locking positively corresponded to SiN performance under multi-talker babbles and SSN, respectively. Finally, we investigated how age and hearing loss affected SiN perception through phase-locked activities via mediation analyses. We showed that both types of activities significantly mediated the relation between age/hearing loss and SiN perception but in distinct manners. Specifically, FFR decreased with age and high-frequency hearing loss which in turn contributed to poorer SiN performance but increased with low-frequency hearing loss which in turn contributed to better SiN performance under multi-talker babbles. Slow-envelope phase-locking increased with age and hearing loss which in turn contributed to better SiN performance under both SSN and multi-talker babbles. Taken together, the present study provided evidence for distinct neural mechanisms of early-stage auditory phase-locked encoding of different acoustic properties through which ageing affects SiN perception.
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Affiliation(s)
- Guangting Mai
- National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham NG1 5DU, UK; Academic Unit of Mental Health and Clinical Neurosciences, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK; Department of Experimental Psychology, University College London, London WC1H 0AP, UK.
| | - Peter Howell
- Department of Experimental Psychology, University College London, London WC1H 0AP, UK
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8
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Suess N, Hauswald A, Reisinger P, Rösch S, Keitel A, Weisz N. Cortical tracking of formant modulations derived from silently presented lip movements and its decline with age. Cereb Cortex 2022; 32:4818-4833. [PMID: 35062025 PMCID: PMC9627034 DOI: 10.1093/cercor/bhab518] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 11/26/2022] Open
Abstract
The integration of visual and auditory cues is crucial for successful processing of speech, especially under adverse conditions. Recent reports have shown that when participants watch muted videos of speakers, the phonological information about the acoustic speech envelope, which is associated with but independent from the speakers' lip movements, is tracked by the visual cortex. However, the speech signal also carries richer acoustic details, for example, about the fundamental frequency and the resonant frequencies, whose visuophonological transformation could aid speech processing. Here, we investigated the neural basis of the visuo-phonological transformation processes of these more fine-grained acoustic details and assessed how they change as a function of age. We recorded whole-head magnetoencephalographic (MEG) data while the participants watched silent normal (i.e., natural) and reversed videos of a speaker and paid attention to their lip movements. We found that the visual cortex is able to track the unheard natural modulations of resonant frequencies (or formants) and the pitch (or fundamental frequency) linked to lip movements. Importantly, only the processing of natural unheard formants decreases significantly with age in the visual and also in the cingulate cortex. This is not the case for the processing of the unheard speech envelope, the fundamental frequency, or the purely visual information carried by lip movements. These results show that unheard spectral fine details (along with the unheard acoustic envelope) are transformed from a mere visual to a phonological representation. Aging affects especially the ability to derive spectral dynamics at formant frequencies. As listening in noisy environments should capitalize on the ability to track spectral fine details, our results provide a novel focus on compensatory processes in such challenging situations.
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Affiliation(s)
- Nina Suess
- Department of Psychology, Centre for Cognitive Neuroscience, University of Salzburg, Salzburg 5020, Austria
| | - Anne Hauswald
- Department of Psychology, Centre for Cognitive Neuroscience, University of Salzburg, Salzburg 5020, Austria
| | - Patrick Reisinger
- Department of Psychology, Centre for Cognitive Neuroscience, University of Salzburg, Salzburg 5020, Austria
| | - Sebastian Rösch
- Department of Otorhinolaryngology, Head and Neck Surgery, Paracelsus Medical University Salzburg, University Hospital Salzburg, Salzburg 5020, Austria
| | - Anne Keitel
- School of Social Sciences, University of Dundee, Dundee DD1 4HN, UK
| | - Nathan Weisz
- Department of Psychology, Centre for Cognitive Neuroscience, University of Salzburg, Salzburg 5020, Austria
- Department of Psychology, Neuroscience Institute, Christian Doppler University Hospital, Paracelsus Medical University, Salzburg 5020, Austria
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9
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Tinnemore AR, Montero L, Gordon-Salant S, Goupell MJ. The recognition of time-compressed speech as a function of age in listeners with cochlear implants or normal hearing. Front Aging Neurosci 2022; 14:887581. [PMID: 36247992 PMCID: PMC9557069 DOI: 10.3389/fnagi.2022.887581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Speech recognition is diminished when a listener has an auditory temporal processing deficit. Such deficits occur in listeners over 65 years old with normal hearing (NH) and with age-related hearing loss, but their source is still unclear. These deficits may be especially apparent when speech occurs at a rapid rate and when a listener is mostly reliant on temporal information to recognize speech, such as when listening with a cochlear implant (CI) or to vocoded speech (a CI simulation). Assessment of the auditory temporal processing abilities of adults with CIs across a wide range of ages should better reveal central or cognitive sources of age-related deficits with rapid speech because CI stimulation bypasses much of the cochlear encoding that is affected by age-related peripheral hearing loss. This study used time-compressed speech at four different degrees of time compression (0, 20, 40, and 60%) to challenge the auditory temporal processing abilities of younger, middle-aged, and older listeners with CIs or with NH. Listeners with NH were presented vocoded speech at four degrees of spectral resolution (unprocessed, 16, 8, and 4 channels). Results showed an interaction between age and degree of time compression. The reduction in speech recognition associated with faster rates of speech was greater for older adults than younger adults. The performance of the middle-aged listeners was more similar to that of the older listeners than to that of the younger listeners, especially at higher degrees of time compression. A measure of cognitive processing speed did not predict the effects of time compression. These results suggest that central auditory changes related to the aging process are at least partially responsible for the auditory temporal processing deficits seen in older listeners, rather than solely peripheral age-related changes.
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Affiliation(s)
- Anna R. Tinnemore
- Neuroscience and Cognitive Science Program, University of Maryland, College Park, College Park, MD, United States
- Department of Hearing and Speech Sciences, University of Maryland, College Park, College Park, MD, United States
- *Correspondence: Anna R. Tinnemore,
| | - Lauren Montero
- Department of Hearing and Speech Sciences, University of Maryland, College Park, College Park, MD, United States
| | - Sandra Gordon-Salant
- Neuroscience and Cognitive Science Program, University of Maryland, College Park, College Park, MD, United States
- Department of Hearing and Speech Sciences, University of Maryland, College Park, College Park, MD, United States
| | - Matthew J. Goupell
- Neuroscience and Cognitive Science Program, University of Maryland, College Park, College Park, MD, United States
- Department of Hearing and Speech Sciences, University of Maryland, College Park, College Park, MD, United States
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Sauvé SA, Marozeau J, Rich Zendel B. The effects of aging and musicianship on the use of auditory streaming cues. PLoS One 2022; 17:e0274631. [PMID: 36137151 PMCID: PMC9498935 DOI: 10.1371/journal.pone.0274631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 08/31/2022] [Indexed: 11/22/2022] Open
Abstract
Auditory stream segregation, or separating sounds into their respective sources and tracking them over time, is a fundamental auditory ability. Previous research has separately explored the impacts of aging and musicianship on the ability to separate and follow auditory streams. The current study evaluated the simultaneous effects of age and musicianship on auditory streaming induced by three physical features: intensity, spectral envelope and temporal envelope. In the first study, older and younger musicians and non-musicians with normal hearing identified deviants in a four-note melody interleaved with distractors that were more or less similar to the melody in terms of intensity, spectral envelope and temporal envelope. In the second study, older and younger musicians and non-musicians participated in a dissimilarity rating paradigm with pairs of melodies that differed along the same three features. Results suggested that auditory streaming skills are maintained in older adults but that older adults rely on intensity more than younger adults while musicianship is associated with increased sensitivity to spectral and temporal envelope, acoustic features that are typically less effective for stream segregation, particularly in older adults.
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Affiliation(s)
- Sarah A. Sauvé
- Division of Community Health and Humanities, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
- * E-mail:
| | - Jeremy Marozeau
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Benjamin Rich Zendel
- Division of Community Health and Humanities, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada
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11
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Sauvé SA, Bolt ELW, Nozaradan S, Zendel BR. Aging effects on neural processing of rhythm and meter. Front Aging Neurosci 2022; 14:848608. [PMID: 36118692 PMCID: PMC9475293 DOI: 10.3389/fnagi.2022.848608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
When listening to musical rhythm, humans can perceive and move to beat-like metrical pulses. Recently, it has been hypothesized that meter perception is related to brain activity responding to the acoustic fluctuation of the rhythmic input, with selective enhancement of the brain response elicited at meter-related frequencies. In the current study, electroencephalography (EEG) was recorded while younger (<35) and older (>60) adults listened to rhythmic patterns presented at two different tempi while intermittently performing a tapping task. Despite significant hearing loss compared to younger adults, older adults showed preserved brain activity to the rhythms. However, age effects were observed in the distribution of amplitude across frequencies. Specifically, in contrast with younger adults, older adults showed relatively larger amplitude at the frequency corresponding to the rate of individual events making up the rhythms as compared to lower meter-related frequencies. This difference is compatible with larger N1-P2 potentials as generally observed in older adults in response to acoustic onsets, irrespective of meter perception. These larger low-level responses to sounds have been linked to processes by which age-related hearing loss would be compensated by cortical sensory mechanisms. Importantly, this low-level effect would be associated here with relatively reduced neural activity at lower frequencies corresponding to higher-level metrical grouping of the acoustic events, as compared to younger adults.
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12
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Farahani ED, Wouters J, van Wieringen A. Age-related hearing loss is associated with alterations in temporal envelope processing in different neural generators along the auditory pathway. Front Neurol 2022; 13:905017. [PMID: 35989932 PMCID: PMC9389009 DOI: 10.3389/fneur.2022.905017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 07/11/2022] [Indexed: 11/22/2022] Open
Abstract
People with age-related hearing loss suffer from speech understanding difficulties, even after correcting for differences in hearing audibility. These problems are not only attributed to deficits in audibility but are also associated with changes in central temporal processing. The goal of this study is to obtain an understanding of potential alterations in temporal envelope processing for middle-aged and older persons with and without hearing impairment. The time series of activity of subcortical and cortical neural generators was reconstructed using a minimum-norm imaging technique. This novel technique allows for reconstructing a wide range of neural generators with minimal prior assumptions regarding the number and location of the generators. The results indicated that the response strength and phase coherence of middle-aged participants with hearing impairment (HI) were larger than for normal-hearing (NH) ones. In contrast, for the older participants, a significantly smaller response strength and phase coherence were observed in the participants with HI than the NH ones for most modulation frequencies. Hemispheric asymmetry in the response strength was also altered in middle-aged and older participants with hearing impairment and showed asymmetry toward the right hemisphere. Our brain source analyses show that age-related hearing loss is accompanied by changes in the temporal envelope processing, although the nature of these changes varies with age.
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13
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Granados Barbero R, Ghesquière P, Wouters J. Development of Atypical Reading at Ages 5 to 9 Years and Processing of Speech Envelope Modulations in the Brain. Front Comput Neurosci 2022; 16:894578. [PMID: 35782088 PMCID: PMC9248325 DOI: 10.3389/fncom.2022.894578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/09/2022] [Indexed: 11/25/2022] Open
Abstract
Different studies have suggested that during speech processing readers with dyslexia present atypical levels of neural entrainment as well as atypical functional hemispherical asymmetries in comparison with typical readers. In this study, we evaluated these differences in children and the variation with age before and after starting with formal reading instruction. Synchronized neural auditory processing activity was quantified based on auditory steady-state responses (ASSRs) from EEG recordings. The stimulation was modulated at syllabic and phonemic fluctuation rates present in speech. We measured the brain activation patterns and the hemispherical asymmetries in children at three age points (5, 7, and 9 years old). Despite the well-known heterogeneity during developmental stages, especially in children and in dyslexia, we could extract meaningful common oscillatory patterns. The analyses included (1) the estimations of source localization, (2) hemispherical preferences using a laterality index, measures of neural entrainment, (3) signal-to-noise ratios (SNRs), and (4) connectivity using phase coherence measures. In this longitudinal study, we confirmed that the existence of atypical levels of neural entrainment and connectivity already exists at pre-reading stages. Overall, these measures reflected a lower ability of the dyslectic brain to synchronize with syllabic rate stimulation. In addition, our findings reinforced the hypothesis of a later maturation of the processing of beta rhythms in dyslexia. This investigation emphasizes the importance of longitudinal studies in dyslexia, especially in children, where neural oscillatory patterns as well as differences between typical and atypical developing children can vary in the span of a year.
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Affiliation(s)
- Raúl Granados Barbero
- Research Group Experimental ORL, Department of Neurosciences, Katholieke University of Leuven, Leuven, Belgium
- *Correspondence: Raúl Granados Barbero
| | - Pol Ghesquière
- Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, Katholieke University of Leuven, Leuven, Belgium
| | - Jan Wouters
- Research Group Experimental ORL, Department of Neurosciences, Katholieke University of Leuven, Leuven, Belgium
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14
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Güntekin B, Aktürk T, Arakaki X, Bonanni L, Del Percio C, Edelmayer R, Farina F, Ferri R, Hanoğlu L, Kumar S, Lizio R, Lopez S, Murphy B, Noce G, Randall F, Sack AT, Stocchi F, Yener G, Yıldırım E, Babiloni C. Are there consistent abnormalities in event-related EEG oscillations in patients with Alzheimer's disease compared to other diseases belonging to dementia? Psychophysiology 2022; 59:e13934. [PMID: 34460957 DOI: 10.1111/psyp.13934] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 07/31/2021] [Accepted: 08/09/2021] [Indexed: 01/30/2023]
Abstract
Cerebrospinal and structural-molecular neuroimaging in-vivo biomarkers are recommended for diagnostic purposes in Alzheimer's disease (AD) and other dementias; however, they do not explain the effects of AD neuropathology on neurophysiological mechanisms underpinning cognitive processes. Here, an Expert Panel from the Electrophysiology Professional Interest Area of the Alzheimer's Association reviewed the field literature and reached consensus on the event-related electroencephalographic oscillations (EROs) that show consistent abnormalities in patients with significant cognitive deficits due to Alzheimer's, Parkinson's (PD), Lewy body (LBD), and cerebrovascular diseases. Converging evidence from oddball paradigms showed that, as compared to cognitively unimpaired (CU) older adults, AD patients had lower amplitude in widespread delta (>4 Hz) and theta (4-7 Hz) phase-locked EROs as a function of disease severity. Similar effects were also observed in PD, LBD, and/or cerebrovascular cognitive impairment patients. Non-phase-locked alpha (8-12 Hz) and beta (13-30 Hz) oscillations were abnormally reduced (event-related desynchronization, ERD) in AD patients relative to CU. However, studies on patients with other dementias remain lacking. Delta and theta phase-locked EROs during oddball tasks may be useful neurophysiological biomarkers of cognitive systems at work in heuristic and intervention clinical trials performed in AD patients, but more research is needed regarding their potential role for other dementias.
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Affiliation(s)
- Bahar Güntekin
- Research Institute for Health Sciences and Technologies (SABITA), Regenerative and Restorative Medicine Research Center (REMER), Clinical Electrophysiology, Neuroimaging and Neuromodulation Lab, Istanbul Medipol University, Istanbul, Turkey
- Department of Biophysics, School of Medicine, Istanbul Medipol University, Istanbul, Turkey
| | - Tuba Aktürk
- Research Institute for Health Sciences and Technologies (SABITA), Regenerative and Restorative Medicine Research Center (REMER), Clinical Electrophysiology, Neuroimaging and Neuromodulation Lab, Istanbul Medipol University, Istanbul, Turkey
- Vocational School, Program of Electroneurophysiology, Istanbul Medipol University, Istanbul, Turkey
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | | | - Laura Bonanni
- Department of Neuroscience Imaging and Clinical Sciences and CESI, University G d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Claudio Del Percio
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Rome, Italy
| | | | - Francesca Farina
- School of Psychology, Trinity College Dublin, Dublin, Ireland
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | | | - Lütfü Hanoğlu
- Department of Neurology, School of Medicine, Istanbul Medipol University, Istanbul, Turkey
| | - Sanjeev Kumar
- Adult Neurodevelopmental and Geriatric Psychiatry Division, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | | | - Susanna Lopez
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Rome, Italy
| | | | | | - Fiona Randall
- Vertex Pharmaceuticals Incorporated, Boston, Massachusetts, USA
| | - Alexander T Sack
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Fabrizio Stocchi
- Institute for Research and Medical Care, IRCCS San Raffaele Pisana, Rome, Italy
| | - Görsev Yener
- Izmir Biomedicine and Genome Center, Dokuz Eylul University Health Campus, Izmir, Turkey
| | - Ebru Yıldırım
- Research Institute for Health Sciences and Technologies (SABITA), Regenerative and Restorative Medicine Research Center (REMER), Clinical Electrophysiology, Neuroimaging and Neuromodulation Lab, Istanbul Medipol University, Istanbul, Turkey
- Vocational School, Program of Electroneurophysiology, Istanbul Medipol University, Istanbul, Turkey
| | - Claudio Babiloni
- Alzheimer's Association, Chicago, Illinois, USA
- Institute for Research and Medical Care, Hospital San Raffaele of Cassino, Cassino, Italy
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15
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Irsik VC, Johnsrude IS, Herrmann B. Age-related deficits in dip-listening evident for isolated sentences but not for spoken stories. Sci Rep 2022; 12:5898. [PMID: 35393472 PMCID: PMC8991280 DOI: 10.1038/s41598-022-09805-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 03/23/2022] [Indexed: 12/03/2022] Open
Abstract
Fluctuating background sounds facilitate speech intelligibility by providing speech ‘glimpses’ (masking release). Older adults benefit less from glimpses, but masking release is typically investigated using isolated sentences. Recent work indicates that using engaging, continuous speech materials (e.g., spoken stories) may qualitatively alter speech-in-noise listening. Moreover, neural sensitivity to different amplitude envelope profiles (ramped, damped) changes with age, but whether this affects speech listening is unknown. In three online experiments, we investigate how masking release in younger and older adults differs for masked sentences and stories, and how speech intelligibility varies with masker amplitude profile. Intelligibility was generally greater for damped than ramped maskers. Masking release was reduced in older relative to younger adults for disconnected sentences, and stories with a randomized sentence order. Critically, when listening to stories with an engaging and coherent narrative, older adults demonstrated equal or greater masking release compared to younger adults. Older adults thus appear to benefit from ‘glimpses’ as much as, or more than, younger adults when the speech they are listening to follows a coherent topical thread. Our results highlight the importance of cognitive and motivational factors for speech understanding, and suggest that previous work may have underestimated speech-listening abilities in older adults.
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Affiliation(s)
- Vanessa C Irsik
- Department of Psychology & The Brain and Mind Institute, The University of Western Ontario, London, ON, N6A 3K7, Canada.
| | - Ingrid S Johnsrude
- Department of Psychology & The Brain and Mind Institute, The University of Western Ontario, London, ON, N6A 3K7, Canada.,School of Communication and Speech Disorders, The University of Western Ontario, London, ON, N6A 5B7, Canada
| | - Björn Herrmann
- Department of Psychology & The Brain and Mind Institute, The University of Western Ontario, London, ON, N6A 3K7, Canada.,Rotman Research Institute, Baycrest, Toronto, ON, M6A 2E1, Canada.,Department of Psychology, University of Toronto, Toronto, ON, M5S 1A1, Canada
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16
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DeVries L, Anderson S, Goupell MJ, Smith E, Gordon-Salant S. Effects of aging and hearing loss on perceptual and electrophysiological measures of pulse-rate discrimination. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 151:1639. [PMID: 35364956 PMCID: PMC8916844 DOI: 10.1121/10.0009399] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 01/10/2022] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
Auditory temporal processing declines with age, leading to potential deleterious effects on communication. In young normal-hearing listeners, perceptual rate discrimination is rate limited around 300 Hz. It is not known whether this rate limitation is similar in older listeners with hearing loss. The purpose of this study was to investigate age- and hearing-loss-related rate limitations on perceptual rate discrimination, and age- and hearing-loss-related effects on neural representation of these stimuli. Younger normal-hearing, older normal-hearing, and older hearing-impaired listeners performed a pulse-rate discrimination task at rates of 100, 200, 300, and 400 Hz. Neural phase locking was assessed using the auditory steady-state response. Finally, a battery of non-auditory cognitive tests was administered. Younger listeners had better rate discrimination, higher phase locking, and higher cognitive scores compared to both groups of older listeners. Aging, but not hearing loss, diminished neural-rate encoding and perceptual performance; however, there was no relationship between the perceptual and neural measures. Higher cognitive scores were correlated with improved perceptual performance, but not with neural phase locking. This study shows that aging, rather than hearing loss, may be a stronger contributor to poorer temporal processing, and cognitive factors such as processing speed and inhibitory control may be related to these declines.
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Affiliation(s)
- Lindsay DeVries
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
| | - Samira Anderson
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
| | - Matthew J Goupell
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
| | - Ed Smith
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
| | - Sandra Gordon-Salant
- Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland 20742, USA
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17
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Märcher-Rørsted J, Encina-Llamas G, Dau T, Liberman MC, Wu PZ, Hjortkjær J. Age-related reduction in frequency-following responses as a potential marker of cochlear neural degeneration. Hear Res 2021; 414:108411. [PMID: 34929535 DOI: 10.1016/j.heares.2021.108411] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 12/03/2021] [Accepted: 12/06/2021] [Indexed: 11/28/2022]
Abstract
Healthy aging may be associated with neural degeneration in the cochlea even before clinical hearing loss emerges. Reduction in frequency-following responses (FFRs) to tonal carriers in older clinically normal-hearing listeners has previously been reported, and has been argued to reflect an age-dependent decline in temporal processing in the central auditory system. Alternatively, age-dependent loss of auditory nerve fibers (ANFs) may have little effect on audiometric sensitivity and yet compromise the precision of neural phase-locking relying on joint activity across populations of fibers. This peripheral loss may, in turn, contribute to reduced neural synchrony in the brainstem as reflected in the FFR. Here, we combined human electrophysiology and auditory nerve (AN) modeling to investigate whether age-related changes in the FFR would be consistent with peripheral neural degeneration. FFRs elicited by pure tones and frequency sweeps at carrier frequencies between 200 and 1200 Hz were obtained in older (ages 48-76) and younger (ages 20-30) listeners, both groups having clinically normal audiometric thresholds up to 6 kHz. The same stimuli were presented to a computational model of the AN in which age-related loss of hair cells or ANFs was modelled using human histopathological data. In the older human listeners, the measured FFRs to both sweeps and pure tones were found to be reduced across the carrier frequencies examined. These FFR reductions were consistent with model simulations of age-related ANF loss. In model simulations, the phase-locked response produced by the population of remaining fibers decreased proportionally with increasing loss of the ANFs. Basal-turn loss of inner hair cells also reduced synchronous activity at lower frequencies, albeit to a lesser degree. Model simulations of age-related threshold elevation further indicated that outer hair cell dysfunction had no negative effect on phase-locked AN responses. These results are consistent with a peripheral source of the FFR reductions observed in older normal-hearing listeners, and indicate that FFRs at lower carrier frequencies may potentially be a sensitive marker of peripheral neural degeneration.
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Affiliation(s)
- Jonatan Märcher-Rørsted
- Hearing Systems Section, Department of Health Technology, Technical University of Denmark, Ørsteds Plads, Building 352, DK-2800 Kgs. Lyngby, Denmark
| | - Gerard Encina-Llamas
- Hearing Systems Section, Department of Health Technology, Technical University of Denmark, Ørsteds Plads, Building 352, DK-2800 Kgs. Lyngby, Denmark
| | - Torsten Dau
- Hearing Systems Section, Department of Health Technology, Technical University of Denmark, Ørsteds Plads, Building 352, DK-2800 Kgs. Lyngby, Denmark
| | - M Charles Liberman
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA 02114 USA
| | - Pei-Zhe Wu
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear, Boston, MA 02114 USA
| | - Jens Hjortkjær
- Hearing Systems Section, Department of Health Technology, Technical University of Denmark, Ørsteds Plads, Building 352, DK-2800 Kgs. Lyngby, Denmark; Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, DK-2650 Hvidovre, Denmark.
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18
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Mossad O, Nent E, Woltemate S, Folschweiller S, Buescher JM, Schnepf D, Erny D, Staeheli P, Bartos M, Szalay A, Stecher B, Vital M, Sauer JF, Lämmermann T, Prinz M, Blank T. Microbiota-dependent increase in δ-valerobetaine alters neuronal function and is responsible for age-related cognitive decline. NATURE AGING 2021; 1:1127-1136. [PMID: 37117525 DOI: 10.1038/s43587-021-00141-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 10/25/2021] [Indexed: 04/30/2023]
Abstract
Understanding the physiological origins of age-related cognitive decline is of critical importance given the rising age of the world's population1. Previous work in animal models has established a strong link between cognitive performance and the microbiota2-5, and it is known that the microbiome undergoes profound remodeling in older adults6. Despite growing evidence for the association between age-related cognitive decline and changes in the gut microbiome, the mechanisms underlying such interactions between the brain and the gut are poorly understood. Here, using fecal microbiota transplantation (FMT), we demonstrate that age-related remodeling of the gut microbiota leads to decline in cognitive function in mice and that this impairment can be rescued by transplantation of microbiota from young animals. Moreover, using a metabolomic approach, we found elevated concentrations of δ-valerobetaine, a gut microbiota-derived metabolite, in the blood and brain of aged mice and older adults. We then demonstrated that δ-valerobetaine is deleterious to learning and memory processes in mice. At the neuronal level, we showed that δ-valerobetaine modulates inhibitory synaptic transmission and neuronal network activity. Finally, we identified specific bacterial taxa that significantly correlate with δ-valerobetaine levels in the brain. Based on our findings, we propose that δ-valerobetaine contributes to microbiota-driven brain aging and that the associated mechanisms represent a promising target for countering age-related cognitive decline.
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Affiliation(s)
- Omar Mossad
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Elisa Nent
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Sabrina Woltemate
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Shani Folschweiller
- Faculty of Biology, University of Freiburg, Freiburg, Germany
- Institute of Physiology I, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Joerg M Buescher
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Daniel Schnepf
- Institute of Virology, Medical Center University of Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs University Freiburg, Freiburg, Germany
| | - Daniel Erny
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Berta-Ottenstein-Programme, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Peter Staeheli
- Institute of Virology, Medical Center University of Freiburg, Freiburg, Germany
- Berta-Ottenstein-Programme, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Marlene Bartos
- Institute of Physiology I, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | | | - Bärbel Stecher
- Max-von-Pettenkofer Institute, LMU Munich, Munich, Germany
- German Center for Infection Research (DZIF), partner site LMU Munich, Munich, Germany
| | - Marius Vital
- Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Jonas F Sauer
- Institute of Physiology I, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tim Lämmermann
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Marco Prinz
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
- Center for NeuroModulation, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Thomas Blank
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
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19
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Rumschlag JA, Razak KA. Age-related changes in event related potentials, steady state responses and temporal processing in the auditory cortex of mice with severe or mild hearing loss. Hear Res 2021; 412:108380. [PMID: 34758398 DOI: 10.1016/j.heares.2021.108380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 08/19/2021] [Accepted: 10/19/2021] [Indexed: 12/20/2022]
Abstract
Age-related changes in auditory processing affect the quality of life of older adults with and without hearing loss. To distinguish between the effects of sensorineural hearing loss and aging on cortical processing, the main goal of the present study was to compare cortical responses using the same stimulus paradigms and recording conditions in two strains of mice (C57BL/6J and FVB) that differ in the degree of age-related hearing loss. Electroencephalogram (EEG) recordings were obtained from freely moving young and old mice using epidural screw electrodes. We measured event related potentials (ERP) and 40 Hz auditory steady-state responses (ASSR). We used a novel stimulus, termed the gap-ASSR stimulus, which elicits an ASSR by rapidly presenting short gaps in continuous noise. By varying the gap widths and modulation depths, we probed the limits of temporal processing in young and old mice. Temporal fidelity of ASSR and gap-ASSR responses were measured as phase consistency across trials (inter-trial phase clustering; ITPC). The old C57 mice, which show severe hearing loss, produced larger ERP amplitudes compared to young mice. Despite robust ERPs, the old C57 mice showed significantly diminished ITPC in the ASSR and gap-ASSR responses, even with 100% modulation depth. The FVB mice, which show mild hearing loss with age, generated similar ERP amplitudes and ASSR ITPC across the age groups tested. However, the old FVB mice showed decreased gap-ASSR responses compared to young mice, particularly for modulation depths <100%. The C57 mice data suggest that severe presbycusis leads to increased gain in the auditory cortex, but with reduced temporal fidelity. The FVB mice data suggest that with mild hearing loss, age-related changes in temporal processing become apparent only when tested with more challenging sounds (shorter gaps and shallower modulation).
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Affiliation(s)
| | - Khaleel A Razak
- Graduate Neuroscience Program, Riverside, United States; Psychology Department, University of California, Riverside, United States.
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20
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Granados Barbero R, de Vos A, Ghesquière P, Wouters J. Atypical processing in neural source analysis of speech envelope modulations in adolescents with dyslexia. Eur J Neurosci 2021; 54:7839-7859. [PMID: 34730259 DOI: 10.1111/ejn.15515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 10/01/2021] [Accepted: 10/28/2021] [Indexed: 11/28/2022]
Abstract
Different studies have suggested that language and developmental disorders such as dyslexia are associated with a disturbance of auditory entrainment and of the functional hemispheric asymmetries during speech processing. These disorders typically result from an issue in the phonological component of language that causes problems to represent and manipulate the phonological structure of words at the syllable and/or phoneme level. We used Auditory Steady-State Responses (ASSRs) in EEG recordings to investigate the brain activation and hemisphere asymmetry of theta, alpha, beta and low-gamma range oscillations in typical readers and readers with dyslexia. The aim was to analyse whether the group differences found in previous electrode level studies were caused by a different source activation pattern or conversely was an effect that could be found on the active brain sources. We could not find differences in the brain locations of the main active brain sources. However, we observed differences in the extracted waveforms. The group average of the first DSS component of all signal-to-noise ratios of ASSR at source level was higher than the group averages at the electrode level. These analyses included a lower alpha synchronisation in adolescents with dyslexia and the possibility of compensatory mechanisms in theta, beta and low-gamma frequency bands. The main brain auditory sources were located in cortical regions around the auditory cortex. Thus, the differences observed in auditory EEG experiments would, according to our findings, have their origin in the intrinsic oscillatory mechanisms of the brain cortical sources related to speech perception.
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Affiliation(s)
- Raúl Granados Barbero
- Research Group Experimental ORL, Department of Neurosciences, KU Leuven - University of Leuven, Leuven, Belgium
| | - Astrid de Vos
- Research Group Experimental ORL, Department of Neurosciences, KU Leuven - University of Leuven, Leuven, Belgium.,Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven - University of Leuven, Leuven, Belgium
| | - Pol Ghesquière
- Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven - University of Leuven, Leuven, Belgium
| | - Jan Wouters
- Research Group Experimental ORL, Department of Neurosciences, KU Leuven - University of Leuven, Leuven, Belgium
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21
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Effects of long-term unilateral cochlear implant use on large-scale network synchronization in adolescents. Hear Res 2021; 409:108308. [PMID: 34343851 DOI: 10.1016/j.heares.2021.108308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 11/20/2022]
Abstract
Unilateral cochlear implantation (CI) limits deafness-related changes in the auditory pathways but promotes abnormal cortical preference for the stimulated ear and leaves the opposite ear with little protection from auditory deprivation. In the present study, time-frequency analyses of event-related potentials elicited from stimuli presented to each ear were used to determine effects of unilateral CI use on cortical synchrony. CI-elicited activity in 34 adolescents (15.4±1.9 years of age) who had listened with unilateral CIs for most of their lives prior to bilateral implantation were compared to responses elicited by a 500Hz tone-burst in normal hearing peers. Phase-locking values between 4 and 60Hz were calculated for 171 pairs of 19-cephalic recording electrodes. Ear specific results were found in the normal hearing group: higher synchronization in low frequency bands (theta and alpha) from left ear stimulation in the right hemisphere and more high frequency activity (gamma band) from right ear stimulation in the left hemisphere. In the CI group, increased phase synchronization in the theta and beta frequencies with bursts of gamma activity were elicited by the experienced-right CI between frontal, temporal and parietal cortical regions in both hemispheres, consistent with increased recruitment of cortical areas involved in attention and higher-order processes, potentially to support unilateral listening. By contrast, activity was globally desynchronized in response to initial stimulation of the naïve-left ear, suggesting decoupling of these pathways from the cortical hearing network. These data reveal asymmetric auditory development promoted by unilateral CI use, resulting in an abnormally mature neural network.
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22
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Van Canneyt J, Wouters J, Francart T. Cortical compensation for hearing loss, but not age, in neural tracking of the fundamental frequency of the voice. J Neurophysiol 2021; 126:791-802. [PMID: 34232756 DOI: 10.1152/jn.00156.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Auditory processing is affected by advancing age and hearing loss, but the underlying mechanisms are still unclear. We investigated the effects of age and hearing loss on temporal processing of naturalistic stimuli in the auditory system. We used a recently developed objective measure for neural phase-locking to the fundamental frequency of the voice (f0) which uses continuous natural speech as a stimulus, that is, "f0-tracking." The f0-tracking responses from 54 normal-hearing and 14 hearing-impaired adults of varying ages were analyzed. The responses were evoked by a Flemish story with a male talker and contained contributions from both subcortical and cortical sources. Results indicated that advancing age was related to smaller responses with less cortical response contributions. This is consistent with an age-related decrease in neural phase-locking ability at frequencies in the range of the f0, possibly due to decreased inhibition in the auditory system. Conversely, hearing-impaired subjects displayed larger responses compared with age-matched normal-hearing controls. This was due to additional cortical response contributions in the 38- to 50-ms latency range, which were stronger for participants with more severe hearing loss. This is consistent with hearing-loss-induced cortical reorganization and recruitment of additional neural resources to aid in speech perception.NEW & NOTEWORTHY Previous studies disagree on the effects of age and hearing loss on the neurophysiological processing of the fundamental frequency of the voice (f0), in part due to confounding effects. Using a novel electrophysiological technique, natural speech stimuli, and controlled study design, we quantified and disentangled the effects of age and hearing loss on neural f0 processing. We uncovered evidence for underlying neurophysiological mechanisms, including a cortical compensation mechanism for hearing loss, but not for age.
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Affiliation(s)
| | - Jan Wouters
- ExpORL, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Tom Francart
- ExpORL, Department of Neurosciences, KU Leuven, Leuven, Belgium
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23
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Neural Modulation Transmission Is a Marker for Speech Perception in Noise in Cochlear Implant Users. Ear Hear 2021; 41:591-602. [PMID: 31567565 DOI: 10.1097/aud.0000000000000783] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Cochlear implants (CIs) restore functional hearing in persons with a severe hearing impairment. Despite being one of the most successful bionic prosthesis, performance with CI (in particular speech understanding in noise) varies considerably across its users. The ability of the auditory pathway to encode temporal envelope modulations (TEMs) and the effect of degenerative processes associated with hearing loss on TEM encoding is assumed to be one of the reasons underlying the large intersubject differences in CI performance. The objective of the present study was to investigate how TEM encoding of the stimulated neural ensembles of human CI recipients is related to speech perception in noise (SPIN). DESIGN We used electroencephalography as a noninvasive electrophysiological measure to assess TEM encoding in the auditory pathway of CI users by means of the 40-Hz electrically evoked auditory steady state response (EASSR). Nine CI users with a wide range of SPIN outcome were included in the present study. TEM encoding was assessed for each stimulation electrode of each subject and new metrics; the CI neural modulation transmission difference (CIMTD) and the CI neural modulation transmission index (CIMTI) were developed to quantify the amount of variability in TEM encoding across the stimulated neural ensembles of the CI electrode array. RESULTS EASSR patterns varied across the CI electrode array and subjects. We found a strong correlation (r = 0.89, p = 0.001) between the SPIN outcomes and the variability in EASSR amplitudes across the array as assessed with CIMTD/CIMTI. CONCLUSIONS The results of the present study show that the 40-Hz EASSR can be used to objectively assess the neural encoding of TEMs in human CI recipients. Overall reduced or largely variable TEM encoding of the neural ensembles across the electrode array, as quantified with the CIMTD/CIMTI, is highly correlated with speech perception in noise outcome with a CI.
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Herrmann B, Butler BE. Hearing loss and brain plasticity: the hyperactivity phenomenon. Brain Struct Funct 2021; 226:2019-2039. [PMID: 34100151 DOI: 10.1007/s00429-021-02313-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 06/03/2021] [Indexed: 12/22/2022]
Abstract
Many aging adults experience some form of hearing problems that may arise from auditory peripheral damage. However, it has been increasingly acknowledged that hearing loss is not only a dysfunction of the auditory periphery but also results from changes within the entire auditory system, from periphery to cortex. Damage to the auditory periphery is associated with an increase in neural activity at various stages throughout the auditory pathway. Here, we review neurophysiological evidence of hyperactivity, auditory perceptual difficulties that may result from hyperactivity, and outline open conceptual and methodological questions related to the study of hyperactivity. We suggest that hyperactivity alters all aspects of hearing-including spectral, temporal, spatial hearing-and, in turn, impairs speech comprehension when background sound is present. By focusing on the perceptual consequences of hyperactivity and the potential challenges of investigating hyperactivity in humans, we hope to bring animal and human electrophysiologists closer together to better understand hearing problems in older adulthood.
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Affiliation(s)
- Björn Herrmann
- Rotman Research Institute, Baycrest, Toronto, ON, M6A 2E1, Canada. .,Department of Psychology, University of Toronto, Toronto, ON, Canada.
| | - Blake E Butler
- Department of Psychology & The Brain and Mind Institute, University of Western Ontario, London, ON, Canada.,National Centre for Audiology, University of Western Ontario, London, ON, Canada
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25
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Irsik VC, Almanaseer A, Johnsrude IS, Herrmann B. Cortical Responses to the Amplitude Envelopes of Sounds Change with Age. J Neurosci 2021; 41:5045-5055. [PMID: 33903222 PMCID: PMC8197634 DOI: 10.1523/jneurosci.2715-20.2021] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 02/16/2021] [Accepted: 03/26/2021] [Indexed: 11/21/2022] Open
Abstract
Many older listeners have difficulty understanding speech in noise, when cues to speech-sound identity are less redundant. The amplitude envelope of speech fluctuates dramatically over time, and features such as the rate of amplitude change at onsets (attack) and offsets (decay), signal critical information about the identity of speech sounds. Aging is also thought to be accompanied by increases in cortical excitability, which may differentially alter sensitivity to envelope dynamics. Here, we recorded electroencephalography in younger and older human adults (of both sexes) to investigate how aging affects neural synchronization to 4 Hz amplitude-modulated noises with different envelope shapes (ramped: slow attack and sharp decay; damped: sharp attack and slow decay). We observed that subcortical responses did not differ between age groups, whereas older compared with younger adults exhibited larger cortical responses to sound onsets, consistent with an increase in auditory cortical excitability. Neural activity in older adults synchronized more strongly to rapid-onset, slow-offset (damped) envelopes, was less sinusoidal, and was more peaked. Younger adults demonstrated the opposite pattern, showing stronger synchronization to slow-onset, rapid-offset (ramped) envelopes, as well as a more sinusoidal neural response shape. The current results suggest that age-related changes in the excitability of auditory cortex alter responses to envelope dynamics. This may be part of the reason why older adults experience difficulty understanding speech in noise.SIGNIFICANCE STATEMENT Many middle-aged and older adults report difficulty understanding speech when there is background noise, which can trigger social withdrawal and negative psychosocial health outcomes. The difficulty may be related to age-related changes in how the brain processes temporal sound features. We tested younger and older people on their sensitivity to different envelope shapes, using EEG. Our results demonstrate that aging is associated with heightened sensitivity to sounds with a sharp attack and gradual decay, and sharper neural responses that deviate from the sinusoidal features of the stimulus, perhaps reflecting increased excitability in the aged auditory cortex. Altered responses to temporal sound features may be part of the reason why older adults often experience difficulty understanding speech in social situations.
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Affiliation(s)
- Vanessa C Irsik
- Department of Psychology & the Brain and Mind Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
| | - Ala Almanaseer
- Department of Psychology & the Brain and Mind Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
| | - Ingrid S Johnsrude
- Department of Psychology & the Brain and Mind Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
- School of Communication and Speech Disorders, University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Björn Herrmann
- Department of Psychology & the Brain and Mind Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada
- Rotman Research Institute Baycrest, Toronto, Ontario M6A 2E1, Canada
- Department of Psychology, University of Toronto, Toronto, Ontario M5S 1A1, Canada
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Ianiszewski A, Fuente A, Gagné JP. Auditory brainstem response asymmetries in older adults: An exploratory study using click and speech stimuli. PLoS One 2021; 16:e0251287. [PMID: 33961673 PMCID: PMC8104406 DOI: 10.1371/journal.pone.0251287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 04/25/2021] [Indexed: 11/27/2022] Open
Abstract
Background Some evidence suggests that young adults exhibit a selective laterality of auditory brainstem response (ABR) elicited with speech stimuli. Little is known about such an auditory laterality in older adults. Objective The aim of this study was to investigate possible asymmetric auditory brainstem processing between right and left ear presentation in older adults. Methods Sixty-two older adults presenting with normal hearing thresholds according to their age and who were native speakers of Quebec French participated in this study. ABR was recorded using click and a 40-ms /da/ syllable. ABR was elicited through monaural right and monaural left stimulation. Latency and amplitude for click-and speech-ABR components were compared between right and left ear presentations. In addition, for the /da/ syllable, a fast Fourier transform analysis of the sustained frequency-following response (FFR) of the vowel was performed along with stimulus-to-response and right-left ear correlation analyses. Results No significant differences between right and left ear presentation were found for amplitudes and latencies of the click-ABR components. Significantly shorter latencies for right ear presentation as compared to left ear presentation were observed for onset and offset transient components (V, A and O), sustained components (D and E), and voiced transition components (C) of the speech-ABR. In addition, the spectral amplitude of the fundamental frequency (F0) was significantly larger for the left ear presentation than the right ear presentation. Conclusions Results of this study show that older adults with normal hearing exhibit symmetric encoding for click stimuli at the brainstem level between the right and left ear presentation. However, they present with brainstem asymmetries for the encoding of selective stimulus components of the speech-ABR between the right and left ear presentation. The right ear presentation of a /da/ syllable elicited reduced neural timing for both transient and sustained components compared to the left ear. Conversely, a stronger left ear F0 encoding was observed. These findings suggest that at a preattentive, sensory stage of auditory processing, older adults lateralize speech stimuli similarly to young adults.
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Affiliation(s)
- Alejandro Ianiszewski
- École d'orthophonie et d'audiologie, Faculté de médecine, Université de Montréal, Montréal, Québec, Canada.,Centre de recherche de l'Institut universitaire de gériatrie de Montréal, Montréal, Québec, Canada
| | - Adrian Fuente
- École d'orthophonie et d'audiologie, Faculté de médecine, Université de Montréal, Montréal, Québec, Canada.,Centre de recherche de l'Institut universitaire de gériatrie de Montréal, Montréal, Québec, Canada
| | - Jean-Pierre Gagné
- École d'orthophonie et d'audiologie, Faculté de médecine, Université de Montréal, Montréal, Québec, Canada.,Centre de recherche de l'Institut universitaire de gériatrie de Montréal, Montréal, Québec, Canada
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27
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Granados Barbero R, De Vos A, Wouters J. The identification of predominant auditory steady-state response brain sources in electroencephalography using denoising source separation. Eur J Neurosci 2021; 53:3688-3709. [PMID: 33811405 DOI: 10.1111/ejn.15219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 01/26/2021] [Accepted: 03/29/2021] [Indexed: 12/24/2022]
Abstract
Different approaches have been used to extract auditory steady-state responses (ASSRs) from electroencephalography (EEG) recordings, including region-related electrode configurations (electrode level) and the manual placement of equivalent current dipoles (source level). Inherent limitations of these approaches are the assumption of the anatomical origin and the omission of activity generated by secondary sources. Data-driven methods such as independent component analysis (ICA) seem to avoid these limitations but only to face new others such as the presence of ASSRs with similar properties in different components and the manual selection protocol to select and classify the most relevant components carrying ASSRs. We propose the novel approach of applying a spatial filter to these components in order to extract the most relevant information. We aimed to develop a method based on the reproducibility across trials that performs reliably in low-signal-to-noise ratio (SNR) scenarios using denoising source separation (DSS). DSS combined with ICA successfully reduced the number of components and extracted the most relevant ASSR at 4, 10 and 20 Hz stimulation in group and individual level studies of EEG adolescent data. The anatomical brain location for these low stimulation frequencies showed results in cortical areas with relatively small dispersion. However, for 40 and 80 Hz, results with regard to the number of components and the anatomical origin were less clear. At all stimulation frequencies the outcome measures were consistent with literature, and the partial rejection of inter-subject variability led to more accurate results and higher SNRs. These findings are promising for future applications in group comparison involving pathologies.
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Affiliation(s)
- Raúl Granados Barbero
- Research Group Experimental ORL, Department of Neurosciences, KU Leuven-University of Leuven, Leuven, Belgium
| | - Astrid De Vos
- Research Group Experimental ORL, Department of Neurosciences, KU Leuven-University of Leuven, Leuven, Belgium.,Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven-University of Leuven, Leuven, Belgium
| | - Jan Wouters
- Research Group Experimental ORL, Department of Neurosciences, KU Leuven-University of Leuven, Leuven, Belgium
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28
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Farahani ED, Wouters J, van Wieringen A. Brain mapping of auditory steady-state responses: A broad view of cortical and subcortical sources. Hum Brain Mapp 2021; 42:780-796. [PMID: 33166050 PMCID: PMC7814770 DOI: 10.1002/hbm.25262] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 12/21/2022] Open
Abstract
Auditory steady-state responses (ASSRs) are evoked brain responses to modulated or repetitive acoustic stimuli. Investigating the underlying neural generators of ASSRs is important to gain in-depth insight into the mechanisms of auditory temporal processing. The aim of this study is to reconstruct an extensive range of neural generators, that is, cortical and subcortical, as well as primary and non-primary ones. This extensive overview of neural generators provides an appropriate basis for studying functional connectivity. To this end, a minimum-norm imaging (MNI) technique is employed. We also present a novel extension to MNI which facilitates source analysis by quantifying the ASSR for each dipole. Results demonstrate that the proposed MNI approach is successful in reconstructing sources located both within (primary) and outside (non-primary) of the auditory cortex (AC). Primary sources are detected in different stimulation conditions (four modulation frequencies and two sides of stimulation), thereby demonstrating the robustness of the approach. This study is one of the first investigations to identify non-primary sources. Moreover, we show that the MNI approach is also capable of reconstructing the subcortical activities of ASSRs. Finally, the results obtained using the MNI approach outperform the group-independent component analysis method on the same data, in terms of detection of sources in the AC, reconstructing the subcortical activities and reducing computational load.
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Affiliation(s)
- Ehsan Darestani Farahani
- Research Group Experimental ORL, Department of NeurosciencesKatholieke Universiteit LeuvenLeuvenBelgium
| | - Jan Wouters
- Research Group Experimental ORL, Department of NeurosciencesKatholieke Universiteit LeuvenLeuvenBelgium
| | - Astrid van Wieringen
- Research Group Experimental ORL, Department of NeurosciencesKatholieke Universiteit LeuvenLeuvenBelgium
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29
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Anderson S, Bieber R, Schloss A. Peripheral deficits and phase-locking declines in aging adults. Hear Res 2021; 403:108188. [PMID: 33581668 DOI: 10.1016/j.heares.2021.108188] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 01/16/2021] [Accepted: 01/20/2021] [Indexed: 10/22/2022]
Abstract
Age-related difficulties in speech understanding may arise from a decrease in the neural representation of speech sounds. A loss of outer hair cells or decrease in auditory nerve fibers may lead to a loss of temporal precision that can affect speech clarity. This study's purpose was to evaluate the peripheral contributors to phase-locking strength, a measure of temporal precision, in recordings to a sustained vowel in 30 younger and 30 older listeners with normal to near normal audiometric thresholds. Thresholds were obtained for pure tones and distortion-product otoacoustic emissions (DPOAEs). Auditory brainstem responses (ABRs) were recorded in quiet and in three levels of continuous white noise (+30, +20, and +10 dB SNR). Absolute amplitudes and latencies of Wave I in quiet and of Wave V across presentation conditions, in addition to the slope of Wave V amplitude and latency changes in noise, were calculated from these recordings. Frequency-following responses (FFRs) were recorded to synthesized /ba/ syllables of two durations, 170 and 260 ms, to determine whether age-related phase-locking deficits are more pronounced for stimuli that are sustained for longer durations. Phase locking was calculated for the early and late regions of the steady-state vowel for both syllables. Group differences were found for nearly every measure except for the slopes of Wave V latency and amplitude changes in noise. We found that outer hair cell function (DPOAEs) contributed to the variance in phase locking. However, the ABR and FFR differences were present after covarying for DPOAEs, suggesting the existence of temporal processing deficits in older listeners that are somewhat independent of outer hair cell function.
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Affiliation(s)
- Samira Anderson
- Department of Hearing and Speech Sciences, University of Maryland, College Park, MD 20742, United States.
| | - Rebecca Bieber
- Department of Hearing and Speech Sciences, University of Maryland, College Park, MD 20742, United States.
| | - Alanna Schloss
- Department of Hearing and Speech Sciences, University of Maryland, College Park, MD 20742, United States.
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30
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Gransier R, Hofmann M, van Wieringen A, Wouters J. Stimulus-evoked phase-locked activity along the human auditory pathway strongly varies across individuals. Sci Rep 2021; 11:143. [PMID: 33420231 PMCID: PMC7794304 DOI: 10.1038/s41598-020-80229-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 12/14/2020] [Indexed: 11/23/2022] Open
Abstract
Phase-locking to the temporal envelope of speech is associated with envelope processing and speech perception. The phase-locked activity of the auditory pathway, across modulation frequencies, is generally assessed at group level and shows a decrease in response magnitude with increasing modulation frequency. With the exception of increased activity around 40 and 80 to 100 Hz. Furthermore, little is known about the phase-locked response patterns to modulation frequencies ≤ 20 Hz, which are modulations predominately present in the speech envelope. In the present study we assess the temporal modulation transfer function (TMTFASSR) of the phase-locked activity of the auditory pathway, from 0.5 to 100 Hz at a high-resolution and by means of auditory steady-state responses. Although the group-averaged TMTFASSR corresponds well with those reported in the literature, the individual TMTFASSR shows a remarkable intersubject variability. This intersubject variability is especially present for ASSRs that originate from the cortex and are evoked with modulation frequencies ≤ 20 Hz. Moreover, we found that these cortical phase-locked activity patterns are robust over time. These results show the importance of the individual TMTFASSR when assessing phase-locked activity to envelope fluctuations, which can potentially be used as a marker for auditory processing.
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Affiliation(s)
- Robin Gransier
- Research Group Experimental Oto-rhino-laryngology (ExpORL), Department of Neurosciences, KU Leuven, Herestraat 49, Box 721, 3000, Leuven, Belgium.
| | - Michael Hofmann
- Research Group Experimental Oto-rhino-laryngology (ExpORL), Department of Neurosciences, KU Leuven, Herestraat 49, Box 721, 3000, Leuven, Belgium
| | - Astrid van Wieringen
- Research Group Experimental Oto-rhino-laryngology (ExpORL), Department of Neurosciences, KU Leuven, Herestraat 49, Box 721, 3000, Leuven, Belgium
| | - Jan Wouters
- Research Group Experimental Oto-rhino-laryngology (ExpORL), Department of Neurosciences, KU Leuven, Herestraat 49, Box 721, 3000, Leuven, Belgium
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31
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Atanasova T, Fargier R, Zesiger P, Laganaro M. Dynamics of Word Production in the Transition from Adolescence to Adulthood. NEUROBIOLOGY OF LANGUAGE (CAMBRIDGE, MASS.) 2021; 2:1-21. [PMID: 37213419 PMCID: PMC10158562 DOI: 10.1162/nol_a_00024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 09/09/2020] [Indexed: 05/23/2023]
Abstract
Changes in word production occur across the lifespan. Previous studies have shown electrophysiological, temporal, and functional differences between children and adults accompanying behavioral changes in picture-naming tasks (Laganaro, Tzieropoulos, Fraunfelder, & Zesiger, 2015). Thus, a shift toward adult-like processes in referential word production occurs somewhere between the ages of 13 and 20. Our aim was to investigate when and how children develop adult-like behavior and brain activation in word production. Toward this aim, performance and event-related potentials (ERP) in a referential word production task were recorded and compared for two groups of adolescents (aged 14 to 16 and 17 to 18), children (aged 10 to 13), and young adults (aged 20 to 30). Both groups of adolescents displayed adult-like production latencies, which were longer only for children, while accuracy was lower in the younger adolescents and in children, compared to adults. ERP waveform analysis and topographic pattern analysis revealed significant intergroup differences in key time-windows on stimulus-locked ERPs, both early (150-220 ms)-associated with pre-linguistic processes-and late (280-330 ms)-associated with lexical processes. The results indicate that brain activation underlying referential word production is completely adult-like in 17-year-old adolescents, whereas an intermediate pattern is still observed in adolescents aged 14 to 16 years old, although their production speed, but not their accuracy, is already adult-like.
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Affiliation(s)
| | - Raphaël Fargier
- Laboratoire Parole et Langage, Aix-Marseille University, Marseille, France
| | - Pascal Zesiger
- Faculty of Psychology and Educational Sciences, University of Geneva, Geneva, Switzerland
| | - Marina Laganaro
- Faculty of Psychology and Educational Sciences, University of Geneva, Geneva, Switzerland
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Keshishzadeh S, Garrett M, Verhulst S. Towards Personalized Auditory Models: Predicting Individual Sensorineural Hearing-Loss Profiles From Recorded Human Auditory Physiology. Trends Hear 2021; 25:2331216520988406. [PMID: 33526004 PMCID: PMC7871356 DOI: 10.1177/2331216520988406] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 11/13/2020] [Accepted: 12/21/2020] [Indexed: 01/15/2023] Open
Abstract
Over the past decades, different types of auditory models have been developed to study the functioning of normal and impaired auditory processing. Several models can simulate frequency-dependent sensorineural hearing loss (SNHL) and can in this way be used to develop personalized audio-signal processing for hearing aids. However, to determine individualized SNHL profiles, we rely on indirect and noninvasive markers of cochlear and auditory-nerve (AN) damage. Our progressive knowledge of the functional aspects of different SNHL subtypes stresses the importance of incorporating them into the simulated SNHL profile, but has at the same time complicated the task of accomplishing this on the basis of noninvasive markers. In particular, different auditory-evoked potential (AEP) types can show a different sensitivity to outer-hair-cell (OHC), inner-hair-cell (IHC), or AN damage, but it is not clear which AEP-derived metric is best suited to develop personalized auditory models. This study investigates how simulated and recorded AEPs can be used to derive individual AN- or OHC-damage patterns and personalize auditory processing models. First, we individualized the cochlear model parameters using common methods of frequency-specific OHC-damage quantification, after which we simulated AEPs for different degrees of AN damage. Using a classification technique, we determined the recorded AEP metric that best predicted the simulated individualized cochlear synaptopathy profiles. We cross-validated our method using the data set at hand, but also applied the trained classifier to recorded AEPs from a new cohort to illustrate the generalizability of the method.
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Affiliation(s)
- Sarineh Keshishzadeh
- Hearing Technology @ WAVES, Department of Information Technology, Ghent University, Belgium
| | - Markus Garrett
- Medizinische Physik and Cluster of Excellence Hearing4all, Department of Medical Physics and Acoustics, University of Oldenburg, Oldenburg, Germany
| | - Sarah Verhulst
- Hearing Technology @ WAVES, Department of Information Technology, Ghent University, Belgium
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Farahani ED, Wouters J, van Wieringen A. Neural Generators Underlying Temporal Envelope Processing Show Altered Responses and Hemispheric Asymmetry Across Age. Front Aging Neurosci 2020; 12:596551. [PMID: 33343335 PMCID: PMC7746817 DOI: 10.3389/fnagi.2020.596551] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 11/02/2020] [Indexed: 01/09/2023] Open
Abstract
Speech understanding problems are highly prevalent in the aging population, even when hearing sensitivity is clinically normal. These difficulties are attributed to changes in central temporal processing with age and can potentially be captured by age-related changes in neural generators. The aim of this study is to investigate age-related changes in a wide range of neural generators during temporal processing in middle-aged and older persons with normal audiometric thresholds. A minimum-norm imaging technique is employed to reconstruct cortical and subcortical neural generators of temporal processing for different acoustic modulations. The results indicate that for relatively slow modulations (<50 Hz), the response strength of neural sources is higher in older adults than in younger ones, while the phase-locking does not change. For faster modulations (80 Hz), both the response strength and the phase-locking of neural sources are reduced in older adults compared to younger ones. These age-related changes in temporal envelope processing of slow and fast acoustic modulations are possibly due to loss of functional inhibition, which is accompanied by aging. Both cortical (primary and non-primary) and subcortical neural generators demonstrate similar age-related changes in response strength and phase-locking. Hemispheric asymmetry is also altered in older adults compared to younger ones. Alterations depend on the modulation frequency and side of stimulation. The current findings at source level could have important implications for the understanding of age-related changes in auditory temporal processing and for developing advanced rehabilitation strategies to address speech understanding difficulties in the aging population.
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Affiliation(s)
- Ehsan Darestani Farahani
- Research Group Experimental Oto-rhino-laryngology (ExpORL), Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Jan Wouters
- Research Group Experimental Oto-rhino-laryngology (ExpORL), Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Astrid van Wieringen
- Research Group Experimental Oto-rhino-laryngology (ExpORL), Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
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34
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Enhancing the sensitivity of the envelope-following response for cochlear synaptopathy screening in humans: The role of stimulus envelope. Hear Res 2020; 400:108132. [PMID: 33333426 DOI: 10.1016/j.heares.2020.108132] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 10/25/2020] [Accepted: 11/25/2020] [Indexed: 02/07/2023]
Abstract
Auditory de-afferentation, a permanent reduction in the number of inner-hair-cells and auditory-nerve synapses due to cochlear damage or synaptopathy, can reliably be quantified using temporal bone histology and immunostaining. However, there is an urgent need for non-invasive markers of synaptopathy to study its perceptual consequences in live humans and to develop effective therapeutic interventions. While animal studies have identified candidate auditory-evoked-potential (AEP) markers for synaptopathy, their interpretation in humans has suffered from translational issues related to neural generator differences, unknown hearing-damage histopathologies or lack of measurement sensitivity. To render AEP-based markers of synaptopathy more sensitive and differential to the synaptopathy aspect of sensorineural hearing loss, we followed a combined computational and experimental approach. Starting from the known characteristics of auditory-nerve physiology, we optimized the stimulus envelope to stimulate the available auditory-nerve population optimally and synchronously to generate strong envelope-following-responses (EFRs). We further used model simulations to explore which stimuli evoked a response that was sensitive to synaptopathy, while being maximally insensitive to possible co-existing outer-hair-cell pathologies. We compared the model-predicted trends to AEPs recorded in younger and older listeners (N=44, 24f) who had normal or impaired audiograms with suspected age-related synaptopathy in the older cohort. We conclude that optimal stimulation paradigms for EFR-based quantification of synaptopathy should have sharply rising envelope shapes, a minimal plateau duration of 1.7-2.1 ms for a 120-Hz modulation rate, and inter-peak intervals which contain near-zero amplitudes. From our recordings, the optimal EFR-evoking stimulus had a rectangular envelope shape with a 25% duty cycle and a 95% modulation depth. Older listeners with normal or impaired audiometric thresholds showed significantly reduced EFRs, which were consistent with how (age-induced) synaptopathy affected these responses in the model.
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35
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Kulasingham JP, Brodbeck C, Presacco A, Kuchinsky SE, Anderson S, Simon JZ. High gamma cortical processing of continuous speech in younger and older listeners. Neuroimage 2020; 222:117291. [PMID: 32835821 PMCID: PMC7736126 DOI: 10.1016/j.neuroimage.2020.117291] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/12/2020] [Accepted: 08/16/2020] [Indexed: 12/11/2022] Open
Abstract
Neural processing along the ascending auditory pathway is often associated with a progressive reduction in characteristic processing rates. For instance, the well-known frequency-following response (FFR) of the auditory midbrain, as measured with electroencephalography (EEG), is dominated by frequencies from ∼100 Hz to several hundred Hz, phase-locking to the acoustic stimulus at those frequencies. In contrast, cortical responses, whether measured by EEG or magnetoencephalography (MEG), are typically characterized by frequencies of a few Hz to a few tens of Hz, time-locking to acoustic envelope features. In this study we investigated a crossover case, cortically generated responses time-locked to continuous speech features at FFR-like rates. Using MEG, we analyzed responses in the high gamma range of 70-200 Hz to continuous speech using neural source-localized reverse correlation and the corresponding temporal response functions (TRFs). Continuous speech stimuli were presented to 40 subjects (17 younger, 23 older adults) with clinically normal hearing and their MEG responses were analyzed in the 70-200 Hz band. Consistent with the relative insensitivity of MEG to many subcortical structures, the spatiotemporal profile of these response components indicated a cortical origin with ∼40 ms peak latency and a right hemisphere bias. TRF analysis was performed using two separate aspects of the speech stimuli: a) the 70-200 Hz carrier of the speech, and b) the 70-200 Hz temporal modulations in the spectral envelope of the speech stimulus. The response was dominantly driven by the envelope modulation, with a much weaker contribution from the carrier. Age-related differences were also analyzed to investigate a reversal previously seen along the ascending auditory pathway, whereby older listeners show weaker midbrain FFR responses than younger listeners, but, paradoxically, have stronger cortical low frequency responses. In contrast to both these earlier results, this study did not find clear age-related differences in high gamma cortical responses to continuous speech. Cortical responses at FFR-like frequencies shared some properties with midbrain responses at the same frequencies and with cortical responses at much lower frequencies.
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Affiliation(s)
- Joshua P Kulasingham
- (a)Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, United States.
| | - Christian Brodbeck
- (b)Institute for Systems Research, University of Maryland, College Park, Maryland, United States.
| | - Alessandro Presacco
- (b)Institute for Systems Research, University of Maryland, College Park, Maryland, United States.
| | - Stefanie E Kuchinsky
- (c)Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, Maryland, United States.
| | - Samira Anderson
- (d)Department of Hearing and Speech Sciences, University of Maryland, College Park, Maryland, United States.
| | - Jonathan Z Simon
- (a)Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, United States; (b)Institute for Systems Research, University of Maryland, College Park, Maryland, United States; (e)Department of Biology, University of Maryland, College Park, Maryland, United States.
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36
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Anderson S, Karawani H. Objective evidence of temporal processing deficits in older adults. Hear Res 2020; 397:108053. [PMID: 32863099 PMCID: PMC7669636 DOI: 10.1016/j.heares.2020.108053] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 07/15/2020] [Accepted: 07/28/2020] [Indexed: 12/17/2022]
Abstract
The older listener's ability to understand speech in challenging environments may be affected by impaired temporal processing. This review summarizes objective evidence of degraded temporal processing from studies that have used the auditory brainstem response, auditory steady-state response, the envelope- or frequency-following response, cortical auditory-evoked potentials, and neural tracking of continuous speech. Studies have revealed delayed latencies and reduced amplitudes/phase locking in subcortical responses in older vs. younger listeners, in contrast to enhanced amplitudes of cortical responses in older listeners. Reconstruction accuracy of responses to continuous speech (e.g., cortical envelope tracking) shows over-representation in older listeners. Hearing loss is a factor in many of these studies, even though the listeners would be considered to have clinically normal hearing thresholds. Overall, the ability to draw definitive conclusions regarding these studies is limited by the use of multiple stimulus conditions, small sample sizes, and lack of replication. Nevertheless, these objective measures suggest a need to incorporate new clinical measures to provide a more comprehensive assessment of the listener's speech understanding ability, but more work is needed to determine the most efficacious measure for clinical use.
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Affiliation(s)
- Samira Anderson
- Department of Hearing and Speech Sciences, University of Maryland, College Park, MD 20742, United States.
| | - Hanin Karawani
- Department of Communication Sciences and Disorders, University of Haifa, Haifa, Israel.
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Koerner TK, Muralimanohar RK, Gallun FJ, Billings CJ. Age-Related Deficits in Electrophysiological and Behavioral Measures of Binaural Temporal Processing. Front Neurosci 2020; 14:578566. [PMID: 33192263 PMCID: PMC7654338 DOI: 10.3389/fnins.2020.578566] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/25/2020] [Indexed: 01/15/2023] Open
Abstract
Binaural processing, particularly the processing of interaural phase differences, is important for sound localization and speech understanding in background noise. Age has been shown to impact the neural encoding and perception of these binaural temporal cues even in individuals with clinically normal hearing sensitivity. This work used a new electrophysiological response, called the interaural phase modulation-following response (IPM-FR), to examine the effects of age on the neural encoding of interaural phase difference cues. Relationships between neural recordings and performance on several behavioral measures of binaural processing were used to determine whether the IPM-FR is predictive of interaural phase difference sensitivity and functional speech understanding deficits. Behavioral binaural frequency modulation detection thresholds were measured to assess sensitivity to interaural phase differences while spatial release-from-masking thresholds were used to assess speech understanding abilities in spatialized noise. Thirty adults between the ages of 35 to 74 years with normal low-frequency hearing thresholds were used in this study. Data showed that older participants had weaker neural responses to the interaural phase difference cue and were less able to take advantage of binaural cues for speech understanding compared to younger participants. Results also showed that the IPM-FR was predictive of performance on the binaural frequency modulation detection task, but not on the spatial release-from-masking task after accounting the effects of age. These results confirm previous work that showed that the IPM-FR reflects age-related declines in binaural temporal processing and provide further evidence that this response may represent a useful objective tool for assessing binaural function. However, further research is needed to understand how the IPM-FR is related to speech understanding abilities.
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Affiliation(s)
- Tess K. Koerner
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
| | - Ramesh Kumar Muralimanohar
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
- Department of Otolaryngology/Head and Neck Surgery, Oregon Health & Science University, Portland, OR, United States
| | - Frederick J. Gallun
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
- Department of Otolaryngology/Head and Neck Surgery, Oregon Health & Science University, Portland, OR, United States
| | - Curtis J. Billings
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
- Department of Otolaryngology/Head and Neck Surgery, Oregon Health & Science University, Portland, OR, United States
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A novel approach to investigate subcortical and cortical sensitivity to temporal structure simultaneously. Hear Res 2020; 398:108080. [PMID: 33038827 DOI: 10.1016/j.heares.2020.108080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 09/11/2020] [Accepted: 09/20/2020] [Indexed: 11/24/2022]
Abstract
Hearing loss is associated with changes at the peripheral, subcortical, and cortical auditory stages. Research often focuses on these stages in isolation, but peripheral damage has cascading effects on central processing, and different stages are interconnected through extensive feedforward and feedback projections. Accordingly, assessment of the entire auditory system is needed to understand auditory pathology. Using a novel stimulus paired with electroencephalography in young, normal-hearing adults, we assess neural function at multiple stages of the auditory pathway simultaneously. We employ click trains that repeatedly accelerate then decelerate (3.5 Hz click-rate-modulation) introducing varying inter-click-intervals (4 to 40 ms). We measured the amplitude of cortical potentials, and the latencies and amplitudes of Waves III and V of the auditory brainstem response (ABR), to clicks as a function of preceding inter-click-interval. This allowed us to assess cortical processing of click-rate-modulation, as well as adaptation and neural recovery time in subcortical structures (probably cochlear nuclei and inferior colliculi). Subcortical adaptation to inter-click intervals was reflected in longer latencies. Cortical responses to the 3.5 Hz modulation included phase-locking, probably originating from auditory cortex, and sustained activity likely originating from higher-level cortices. We did not observe any correlations between subcortical and cortical responses. By recording neural responses from different stages of the auditory system simultaneously, we can study functional relationships among levels of the auditory system, which may provide a new and helpful window on hearing and hearing impairment.
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Gransier R, Carlyon RP, Wouters J. Electrophysiological assessment of temporal envelope processing in cochlear implant users. Sci Rep 2020; 10:15406. [PMID: 32958791 PMCID: PMC7506023 DOI: 10.1038/s41598-020-72235-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/18/2020] [Indexed: 11/12/2022] Open
Abstract
Cochlear-implant (CI) users rely on temporal envelope modulations (TEMs) to understand speech, and clinical outcomes depend on the accuracy with which these TEMs are encoded by the electrically-stimulated neural ensembles. Non-invasive EEG measures of this encoding could help clinicians identify and disable electrodes that evoke poor neural responses so as to improve CI outcomes. However, recording EEG during CI stimulation reveals huge stimulation artifacts that are up to orders of magnitude larger than the neural response. Here we used a custom-built EEG system having an exceptionally high sample rate to accurately measure the artefact, which we then removed using linear interpolation so as to reveal the neural response during continuous electrical stimulation. In ten adult CI users, we measured the 40-Hz electrically evoked auditory steady-state response (eASSR) and electrically evoked auditory change complex (eACC) to amplitude-modulated 900-pulses-per-second pulse trains, stimulated in monopolar mode (i.e. the clinical default), and at different modulation depths. We successfully measured artifact-free 40-Hz eASSRs and eACCs. Moreover, we found that the 40-Hz eASSR, in contrast to the eACC, showed substantial responses even at shallow modulation depths. We argue that the 40-Hz eASSR is a clinically feasible objective measure to assess TEM encoding in CI users.
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Affiliation(s)
- Robin Gransier
- Department of Neurosciences, KU Leuven, ExpORL, Herestraat 49, Box 721, 3000, Leuven, Belgium.
| | - Robert P Carlyon
- Cambridge Hearing Group, MRC Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge, CB2 7EF, UK
| | - Jan Wouters
- Department of Neurosciences, KU Leuven, ExpORL, Herestraat 49, Box 721, 3000, Leuven, Belgium
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Age-related changes in the temporal processing of acoustical signals in the auditory cortex of rats. Hear Res 2020; 402:108025. [PMID: 32709399 DOI: 10.1016/j.heares.2020.108025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 06/10/2020] [Accepted: 06/22/2020] [Indexed: 12/28/2022]
Abstract
Age-related hearing loss is manifested primarily by a decreased sensitivity to faint sounds, that is, by elevation of the hearing thresholds. Nevertheless, aging also affects the ability of the auditory system to process temporal parameters of the sound stimulus. To explore the precision and reliability of auditory temporal processing during aging, responses to several types of sound stimuli were recorded from neurons of the auditory cortex (AC) of young and aged anaesthetized Fischer 344 rats. In response to broad-band noise bursts, the aged rats exhibited larger response magnitudes, a higher proportion of monotonic units, and also a larger variability of response magnitudes, suggesting a lower stability of the rate code. Of primary interest were the responses to temporally structured stimuli (amplitude-modulated (AM) noise, frequency-modulated (FM) tones, and click trains) recorded separately in the right and left AC. Significant differences of temporal processing were already found between the neuronal responses in the left and right AC in the young animals: for the click trains, the left hemisphere exhibited a greater responsiveness to higher repetition rates, lower vector strength values, and a lower similarity of responses. The two hemispheres were also affected differently by aging. In the right hemisphere, neurons in the aged animals displayed worse synchronization with the AM noise and clicks, but better synchronization with the FM tone. In the left hemisphere, neuronal synchronization with the stimulus modulation improved at a higher age for all three stimuli. The results show that the ability of the aging auditory system to process temporal parameters of the stimulus strongly depends on the stimulus type and on laterality. Furthermore, the commonly reported age-related decline in the temporal processing ability cannot be regarded as general as, at least at the neuronal level in the AC, objective measures of the temporal representation often exhibit age-related improvement instead of deterioration.
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41
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De Vos A, Vanvooren S, Ghesquière P, Wouters J. Subcortical auditory neural synchronization is deficient in pre-reading children who develop dyslexia. Dev Sci 2020; 23:e12945. [PMID: 32034978 DOI: 10.1111/desc.12945] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 02/03/2020] [Accepted: 02/04/2020] [Indexed: 01/19/2023]
Abstract
Auditory processing of temporal information in speech is sustained by synchronized firing of neurons along the entire auditory pathway. In school-aged children and adults with dyslexia, neural synchronization deficits have been found at cortical levels of the auditory system, however, these deficits do not appear to be present in pre-reading children. An alternative role for subcortical synchronization in reading development and dyslexia has been suggested, but remains debated. By means of a longitudinal study, we assessed cognitive reading-related skills and subcortical auditory steady-state responses (80 Hz ASSRs) in a group of children before formal reading instruction (pre-reading), after 1 year of formal reading instruction (beginning reading), and after 3 years of formal reading instruction (more advanced reading). Children were retrospectively classified into three groups based on family risk and literacy achievement: typically developing children without a family risk for dyslexia, typically developing children with a family risk for dyslexia, and children who developed dyslexia. Our results reveal that children who developed dyslexia demonstrate decreased 80 Hz ASSRs at the pre-reading stage. This effect is no longer present after the onset of reading instruction, due to an atypical developmental increase in 80 Hz ASSRs between the pre-reading and the beginning reading stage. A forward stepwise logistic regression analysis showed that literacy achievement was predictable with an accuracy of 90.4% based on a model including three significant predictors, that is, family risk for dyslexia (R = .31), phonological awareness (R = .23), and 80 Hz ASSRs (R = .26). Given that (1) abnormalities in subcortical ASSRs preceded reading acquisition in children who developed dyslexia and (2) subcortical ASSRs contributed to the prediction of literacy achievement, subcortical auditory synchronization deficits may constitute a pre-reading risk factor in the emergence of dyslexia.
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Affiliation(s)
- Astrid De Vos
- Department of Neurosciences, Research Group Experimental ORL, KU Leuven - University of Leuven, Leuven, Belgium.,Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven - University of Leuven, Leuven, Belgium
| | - Sophie Vanvooren
- Department of Neurosciences, Research Group Experimental ORL, KU Leuven - University of Leuven, Leuven, Belgium.,Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven - University of Leuven, Leuven, Belgium
| | - Pol Ghesquière
- Parenting and Special Education Research Unit, Faculty of Psychology and Educational Sciences, KU Leuven - University of Leuven, Leuven, Belgium
| | - Jan Wouters
- Department of Neurosciences, Research Group Experimental ORL, KU Leuven - University of Leuven, Leuven, Belgium
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Effects of Sensorineural Hearing Loss on Cortical Synchronization to Competing Speech during Selective Attention. J Neurosci 2020; 40:2562-2572. [PMID: 32094201 PMCID: PMC7083526 DOI: 10.1523/jneurosci.1936-19.2020] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 01/17/2020] [Accepted: 01/30/2020] [Indexed: 11/21/2022] Open
Abstract
When selectively attending to a speech stream in multi-talker scenarios, low-frequency cortical activity is known to synchronize selectively to fluctuations in the attended speech signal. Older listeners with age-related sensorineural hearing loss (presbycusis) often struggle to understand speech in such situations, even when wearing a hearing aid. Yet, it is unclear whether a peripheral hearing loss degrades the attentional modulation of cortical speech tracking. Here, we used psychoacoustics and electroencephalography (EEG) in male and female human listeners to examine potential effects of hearing loss on EEG correlates of speech envelope synchronization in cortex. Behaviorally, older hearing-impaired (HI) listeners showed degraded speech-in-noise recognition and reduced temporal acuity compared with age-matched normal-hearing (NH) controls. During EEG recordings, we used a selective attention task with two spatially separated simultaneous speech streams where NH and HI listeners both showed high speech recognition performance. Low-frequency (<10 Hz) envelope-entrained EEG responses were enhanced in the HI listeners, both for the attended speech, but also for tone sequences modulated at slow rates (4 Hz) during passive listening. Compared with the attended speech, responses to the ignored stream were found to be reduced in both HI and NH listeners, allowing for the attended target to be classified from single-trial EEG data with similar high accuracy in the two groups. However, despite robust attention-modulated speech entrainment, the HI listeners rated the competing speech task to be more difficult. These results suggest that speech-in-noise problems experienced by older HI listeners are not necessarily associated with degraded attentional selection. SIGNIFICANCE STATEMENT People with age-related sensorineural hearing loss often struggle to follow speech in the presence of competing talkers. It is currently unclear whether hearing impairment may impair the ability to use selective attention to suppress distracting speech in situations when the distractor is well segregated from the target. Here, we report amplified envelope-entrained cortical EEG responses to attended speech and to simple tones modulated at speech rates (4 Hz) in listeners with age-related hearing loss. Critically, despite increased self-reported listening difficulties, cortical synchronization to speech mixtures was robustly modulated by selective attention in listeners with hearing loss. This allowed the attended talker to be classified from single-trial EEG responses with high accuracy in both older hearing-impaired listeners and age-matched normal-hearing controls.
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Scurry AN, Vercillo T, Nicholson A, Webster M, Jiang F. Aging Impairs Temporal Sensitivity, but not Perceptual Synchrony, Across Modalities. Multisens Res 2019; 32:671-692. [PMID: 31059487 DOI: 10.1163/22134808-20191343] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 02/11/2019] [Indexed: 11/19/2022]
Abstract
Encoding the temporal properties of external signals that comprise multimodal events is a major factor guiding everyday experience. However, during the natural aging process, impairments to sensory processing can profoundly affect multimodal temporal perception. Various mechanisms can contribute to temporal perception, and thus it is imperative to understand how each can be affected by age. In the current study, using three different temporal order judgement tasks (unisensory, multisensory, and sensorimotor), we investigated the effects of age on two separate temporal processes: synchronization and integration of multiple signals. These two processes rely on different aspects of temporal information, either the temporal alignment of processed signals or the integration/segregation of signals arising from different modalities, respectively. Results showed that the ability to integrate/segregate multiple signals decreased with age regardless of the task, and that the magnitude of such impairment correlated across tasks, suggesting a widespread mechanism affected by age. In contrast, perceptual synchrony remained stable with age, revealing a distinct intact mechanism. Overall, results from this study suggest that aging has differential effects on temporal processing, and general impairments with aging may impact global temporal sensitivity while context-dependent processes remain unaffected.
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Affiliation(s)
| | - Tiziana Vercillo
- 2Ernest J. Del Monte Institute for Neuroscience, Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Alexis Nicholson
- 1Department of Psychology, University of Nevada, Reno, NV 89557, USA
| | - Michael Webster
- 1Department of Psychology, University of Nevada, Reno, NV 89557, USA
| | - Fang Jiang
- 1Department of Psychology, University of Nevada, Reno, NV 89557, USA
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Herrmann B, Buckland C, Johnsrude IS. Neural signatures of temporal regularity processing in sounds differ between younger and older adults. Neurobiol Aging 2019; 83:73-85. [DOI: 10.1016/j.neurobiolaging.2019.08.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 08/20/2019] [Accepted: 08/29/2019] [Indexed: 01/02/2023]
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Decruy L, Vanthornhout J, Francart T. Evidence for enhanced neural tracking of the speech envelope underlying age-related speech-in-noise difficulties. J Neurophysiol 2019; 122:601-615. [PMID: 31141449 DOI: 10.1152/jn.00687.2018] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
When we grow older, understanding speech in noise becomes more challenging. Research has demonstrated the role of auditory temporal and cognitive deficits in these age-related speech-in-noise difficulties. To better understand the underlying neural mechanisms, we recruited young, middle-aged, and older normal-hearing adults and investigated the interplay between speech understanding, cognition, and neural tracking of the speech envelope using electroencephalography. The stimuli consisted of natural speech masked by speech-weighted noise or a competing talker and were presented at several subject-specific speech understanding levels. In addition to running speech, we recorded auditory steady-state responses at low modulation frequencies to assess the effect of age on nonspeech sounds. The results show that healthy aging resulted in a supralinear increase in the speech reception threshold, i.e., worse speech understanding, most pronounced for the competing talker. Similarly, advancing age was associated with a supralinear increase in envelope tracking, with a pronounced enhancement for older adults. Additionally, envelope tracking was found to increase with speech understanding, most apparent for older adults. Because we found that worse cognitive scores were associated with enhanced envelope tracking, our results support the hypothesis that enhanced envelope tracking in older adults is the result of a higher activation of brain regions for processing speech, compared with younger adults. From a cognitive perspective, this could reflect the inefficient use of cognitive resources, often observed in behavioral studies. Interestingly, the opposite effect of age was found for auditory steady-state responses, suggesting a complex interplay of different neural mechanisms with advancing age.NEW & NOTEWORTHY We measured neural tracking of the speech envelope across the adult lifespan and found a supralinear increase in envelope tracking with age. Using a more ecologically valid approach than auditory steady-state responses, we found that young and older, as well as middle-aged, normal-hearing adults showed an increase in envelope tracking with increasing speech understanding and that this association is stronger for older adults.
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Affiliation(s)
- Lien Decruy
- ExpORL, Department of Neurosciences, KU Leuven, Leuven, Belgium
| | | | - Tom Francart
- ExpORL, Department of Neurosciences, KU Leuven, Leuven, Belgium
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Parthasarathy A, Bartlett EL, Kujawa SG. Age-related Changes in Neural Coding of Envelope Cues: Peripheral Declines and Central Compensation. Neuroscience 2019; 407:21-31. [DOI: 10.1016/j.neuroscience.2018.12.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/30/2018] [Accepted: 12/03/2018] [Indexed: 12/22/2022]
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47
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Gaskins C, Jaekel BN, Gordon-Salant S, Goupell MJ, Anderson S. Effects of Aging on Perceptual and Electrophysiological Responses to Acoustic Pulse Trains as a Function of Rate. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2019; 62:1087-1098. [PMID: 31026191 PMCID: PMC6802875 DOI: 10.1044/2018_jslhr-h-ascc7-18-0133] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Purpose As pulse rate increases beyond a few hundred Hertz, younger normal-hearing (NH) participants' ability to encode temporal information in band-limited acoustic pulse trains decreases, demonstrating a rate limitation in processing rapid temporal information. Rate discrimination abilities, however, have yet to be investigated in older NH participants-a population that experiences age-related temporal processing deficits. It was hypothesized that age-related temporal processing deficits lead to decreased temporal rate discrimination abilities in older compared with younger NH participants, which could be observed in both perceptual and electrophysiological measurements. Method Fifteen younger and 15 older NH participants were presented acoustic pulse trains with a 4-kHz center frequency and 1-kHz bandwidth at 75 dB SPL monaurally. The pulse rate was 80, 200, or 400 Hz. Just noticeable differences were obtained using an adaptive procedure that instructed the participants to identify the pulse train with the highest pitch. Auditory steady-state responses (ASSRs) were recorded to the same pulse trains with 2 additional rates-20 and 40 Hz. The Digit Symbol Coding and Digit Symbol Search subtests of the Wechsler Adult Intelligence Scale ( Wechsler, 1997 ) were measured as correlates to domain-general cognitive processing speed. Results As rate increased from 80 to 400 Hz, performance on the perceptual rate discrimination task worsened in both groups. ASSR spectral energy also decreased, but only in the older group. Perceptual performance was equivalent between groups across rates. The older group had lower ASSR spectral energy (lower signal-to-noise ratios) at the 400-Hz rate than the younger group, but there were no group differences for the other rates. The overall strength of neural rate representation, along with speed of processing performance, predicted perceptual performance for the 400-Hz rate. Conclusion These results suggest that neural representation at early levels of the auditory system and processing speed are factors in perceptual auditory temporal processing performance, especially in older adults.
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Affiliation(s)
- Casey Gaskins
- Department of Hearing and Speech Sciences, University of Maryland, College Park
| | - Brittany N. Jaekel
- Department of Hearing and Speech Sciences, University of Maryland, College Park
| | | | - Matthew J. Goupell
- Department of Hearing and Speech Sciences, University of Maryland, College Park
| | - Samira Anderson
- Department of Hearing and Speech Sciences, University of Maryland, College Park
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Keller M, Neuschwander P, Meyer M. When right becomes less right: Neural dedifferentiation during suprasegmental speech processing in the aging brain. Neuroimage 2019; 189:886-895. [DOI: 10.1016/j.neuroimage.2019.01.050] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 01/17/2019] [Accepted: 01/17/2019] [Indexed: 01/27/2023] Open
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Modulation of phase-locked neural responses to speech during different arousal states is age-dependent. Neuroimage 2019; 189:734-744. [DOI: 10.1016/j.neuroimage.2019.01.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/08/2018] [Accepted: 01/20/2019] [Indexed: 01/29/2023] Open
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50
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Vercammen C, Goossens T, Undurraga J, Wouters J, van Wieringen A. Electrophysiological and Behavioral Evidence of Reduced Binaural Temporal Processing in the Aging and Hearing Impaired Human Auditory System. Trends Hear 2019; 22:2331216518785733. [PMID: 30022734 PMCID: PMC6053861 DOI: 10.1177/2331216518785733] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A person’s ability to process temporal fine structure information is
indispensable for speech understanding. As speech understanding typically
deteriorates throughout adult life, this study aimed to disentangle age and
hearing impairment (HI)-related changes in binaural temporal processing. This
was achieved by examining neural and behavioral processing of interaural phase
differences (IPDs). Neural IPD processing was studied electrophysiologically
through steady-state activity in the electroencephalogram evoked by periodic
changes in IPDs over time, embedded in the temporal fine structure of acoustic
stimulation. In addition, behavioral IPD discrimination thresholds were
determined for the same stimuli. To disentangle potential effects of age from
those of HI, both measures were applied to six participant groups: young,
middle-aged, and older persons, with either normal hearing or sensorineural HI.
All participants passed a cognitive screening, and stimulus audibility was
controlled for in participants with HI. The results demonstrated that HI changes
neural processing of binaural temporal information for all age-groups included
in this study. These outcomes were revealed, superimposed on age-related changes
that emerge between young adulthood and middle age. Poorer neural outcomes were
also associated with poorer behavioral performance, even though the behavioral
IPD discrimination thresholds were affected by age rather than by HI. The neural
outcomes of this study are the first to evidence and disentangle the dual load
of age and HI on binaural temporal processing. These results could be a valuable
first step toward future research on rehabilitation.
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Affiliation(s)
- Charlotte Vercammen
- 1 Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology, KU Leuven-University of Leuven, Belgium
| | - Tine Goossens
- 1 Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology, KU Leuven-University of Leuven, Belgium
| | - Jaime Undurraga
- 2 Department of Linguistics, The Australian Hearing Hub, Macquarie University, Sydney, Australia.,3 Ear Institute, University College London, London, UK
| | - Jan Wouters
- 1 Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology, KU Leuven-University of Leuven, Belgium
| | - Astrid van Wieringen
- 1 Department of Neurosciences, Research Group Experimental Oto-Rhino-Laryngology, KU Leuven-University of Leuven, Belgium
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