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Sonck R, Vanthornhout J, Bonin E, Francart T. Auditory Steady-State Responses: Multiplexed Amplitude Modulation Frequencies to Reduce Recording Time. Ear Hear 2024:00003446-990000000-00322. [PMID: 39085997 DOI: 10.1097/aud.0000000000001552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
OBJECTIVES This study investigated the efficiency of a multiplexed amplitude-modulated (AM) stimulus in eliciting auditory steady-state responses. The multiplexed AM stimulus was created by simultaneously modulating speech-shaped noise with three frequencies chosen to elicit different neural generators: 3.1, 40.1, and 102.1 Hz. For comparison, a single AM stimulus was created for each of these frequencies, resulting in three single AM conditions and one multiplex AM condition. DESIGN Twenty-two bilaterally normal-hearing participants (18 females) listened for 8 minutes to each type of stimuli. The analysis compared the signal to noise ratios (SNRs) and amplitudes of the evoked responses to the single and multiplexed conditions. RESULTS The results revealed that the SNRs elicited by single AM conditions were, on average, 1.61 dB higher than those evoked by the multiplexed AM condition ( p < 0.05). The single conditions consistently produced a significantly higher SNR when examining various stimulus durations ranging from 1 to 8 minutes. Despite these SNR differences, the frequency spectrum was very similar across and within subjects. In addition, the sensor space patterns across the scalp demonstrated similar trends between the single and multiplexed stimuli for both SNR and amplitudes. Both the single and multiplexed conditions evoked significant auditory steady-state responses within subjects. On average, the multiplexed AM stimulus took 31 minutes for the lower bound of the 95% prediction interval to cross the significance threshold across all three frequencies. In contrast, the single AM stimuli took 45 minutes and 42 seconds. CONCLUSIONS These findings show that the multiplexed AM stimulus is a promising method to reduce the recording time when simultaneously obtaining information from various neural generators.
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Affiliation(s)
- Rien Sonck
- Department of Neurosciences, Research Group Experimental Oto-rhino-laryngology, KU Leuven, Leuven, Belgium
- Grappe Interdisciplinaire de Génoprotéomique Appliquée-Consciousness, Coma Science Group, University of Liège, Liège, Belgium
- Brain Center (C2), University Hospital Center of Liège, Liège, Belgium
- These authors shared first-authorship
| | - Jonas Vanthornhout
- Department of Neurosciences, Research Group Experimental Oto-rhino-laryngology, KU Leuven, Leuven, Belgium
- These authors shared first-authorship
| | - Estelle Bonin
- Grappe Interdisciplinaire de Génoprotéomique Appliquée-Consciousness, Coma Science Group, University of Liège, Liège, Belgium
- Brain Center (C2), University Hospital Center of Liège, Liège, Belgium
| | - Tom Francart
- Department of Neurosciences, Research Group Experimental Oto-rhino-laryngology, KU Leuven, Leuven, Belgium
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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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MacLean J, Stirn J, Sisson A, Bidelman GM. Short- and long-term neuroplasticity interact during the perceptual learning of concurrent speech. Cereb Cortex 2024; 34:bhad543. [PMID: 38212291 PMCID: PMC10839853 DOI: 10.1093/cercor/bhad543] [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: 09/25/2023] [Revised: 12/20/2023] [Accepted: 12/21/2023] [Indexed: 01/13/2024] Open
Abstract
Plasticity from auditory experience shapes the brain's encoding and perception of sound. However, whether such long-term plasticity alters the trajectory of short-term plasticity during speech processing has yet to be investigated. Here, we explored the neural mechanisms and interplay between short- and long-term neuroplasticity for rapid auditory perceptual learning of concurrent speech sounds in young, normal-hearing musicians and nonmusicians. Participants learned to identify double-vowel mixtures during ~ 45 min training sessions recorded simultaneously with high-density electroencephalography (EEG). We analyzed frequency-following responses (FFRs) and event-related potentials (ERPs) to investigate neural correlates of learning at subcortical and cortical levels, respectively. Although both groups showed rapid perceptual learning, musicians showed faster behavioral decisions than nonmusicians overall. Learning-related changes were not apparent in brainstem FFRs. However, plasticity was highly evident in cortex, where ERPs revealed unique hemispheric asymmetries between groups suggestive of different neural strategies (musicians: right hemisphere bias; nonmusicians: left hemisphere). Source reconstruction and the early (150-200 ms) time course of these effects localized learning-induced cortical plasticity to auditory-sensory brain areas. Our findings reinforce the domain-general benefits of musicianship but reveal that successful speech sound learning is driven by a critical interplay between long- and short-term mechanisms of auditory plasticity, which first emerge at a cortical level.
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Affiliation(s)
- Jessica MacLean
- Department of Speech, Language and Hearing Sciences, Indiana University, Bloomington, IN, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, USA
| | - Jack Stirn
- Department of Speech, Language and Hearing Sciences, Indiana University, Bloomington, IN, USA
| | - Alexandria Sisson
- Department of Speech, Language and Hearing Sciences, Indiana University, Bloomington, IN, USA
| | - Gavin M Bidelman
- Department of Speech, Language and Hearing Sciences, Indiana University, Bloomington, IN, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, USA
- Cognitive Science Program, Indiana University, Bloomington, IN, USA
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4
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Parida S, Yurasits K, Cancel VE, Zink ME, Mitchell C, Ziliak MC, Harrison AV, Bartlett EL, Parthasarathy A. Rapid and objective assessment of auditory temporal processing using dynamic amplitude-modulated stimuli. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.28.577641. [PMID: 38352339 PMCID: PMC10862703 DOI: 10.1101/2024.01.28.577641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
Auditory neural coding of speech-relevant temporal cues can be noninvasively probed using envelope following responses (EFRs), neural ensemble responses phase-locked to the stimulus amplitude envelope. EFRs emphasize different neural generators, such as the auditory brainstem or auditory cortex, by altering the temporal modulation rate of the stimulus. EFRs can be an important diagnostic tool to assess auditory neural coding deficits that go beyond traditional audiometric estimations. Existing approaches to measure EFRs use discrete amplitude modulated (AM) tones of varying modulation frequencies, which is time consuming and inefficient, impeding clinical translation. Here we present a faster and more efficient framework to measure EFRs across a range of AM frequencies using stimuli that dynamically vary in modulation rates, combined with spectrally specific analyses that offer optimal spectrotemporal resolution. EFRs obtained from several species (humans, Mongolian gerbils, Fischer-344 rats, and Cba/CaJ mice) showed robust, high-SNR tracking of dynamic AM trajectories (up to 800Hz in humans, and 1.4 kHz in rodents), with a fivefold decrease in recording time and thirtyfold increase in spectrotemporal resolution. EFR amplitudes between dynamic AM stimuli and traditional discrete AM tokens within the same subjects were highly correlated (94% variance explained) across species. Hence, we establish a time-efficient and spectrally specific approach to measure EFRs. These results could yield novel clinical diagnostics for precision audiology approaches by enabling rapid, objective assessment of temporal processing along the entire auditory neuraxis.
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Affiliation(s)
- Satyabrata Parida
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kimberly Yurasits
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA, USA
| | - Victoria E. Cancel
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA, USA
| | - Maggie E. Zink
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA, USA
| | - Claire Mitchell
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA, USA
| | - Meredith C. Ziliak
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Audrey V. Harrison
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Edward L. Bartlett
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, USA
| | - Aravindakshan Parthasarathy
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA, USA
- Department of BioEngineering, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, PA, USA
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5
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Commuri V, Kulasingham JP, Simon JZ. Cortical responses time-locked to continuous speech in the high-gamma band depend on selective attention. Front Neurosci 2023; 17:1264453. [PMID: 38156264 PMCID: PMC10752935 DOI: 10.3389/fnins.2023.1264453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 11/21/2023] [Indexed: 12/30/2023] Open
Abstract
Auditory cortical responses to speech obtained by magnetoencephalography (MEG) show robust speech tracking to the speaker's fundamental frequency in the high-gamma band (70-200 Hz), but little is currently known about whether such responses depend on the focus of selective attention. In this study 22 human subjects listened to concurrent, fixed-rate, speech from male and female speakers, and were asked to selectively attend to one speaker at a time, while their neural responses were recorded with MEG. The male speaker's pitch range coincided with the lower range of the high-gamma band, whereas the female speaker's higher pitch range had much less overlap, and only at the upper end of the high-gamma band. Neural responses were analyzed using the temporal response function (TRF) framework. As expected, the responses demonstrate robust speech tracking of the fundamental frequency in the high-gamma band, but only to the male's speech, with a peak latency of ~40 ms. Critically, the response magnitude depends on selective attention: the response to the male speech is significantly greater when male speech is attended than when it is not attended, under acoustically identical conditions. This is a clear demonstration that even very early cortical auditory responses are influenced by top-down, cognitive, neural processing mechanisms.
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Affiliation(s)
- Vrishab Commuri
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, United States
| | | | - Jonathan Z. Simon
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, United States
- Department of Biology, University of Maryland, College Park, MD, United States
- Institute for Systems Research, University of Maryland, College Park, MD, United States
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6
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Commuri V, Kulasingham JP, Simon JZ. Cortical Responses Time-Locked to Continuous Speech in the High-Gamma Band Depend on Selective Attention. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.20.549567. [PMID: 37546895 PMCID: PMC10401961 DOI: 10.1101/2023.07.20.549567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Auditory cortical responses to speech obtained by magnetoencephalography (MEG) show robust speech tracking to the speaker's fundamental frequency in the high-gamma band (70-200 Hz), but little is currently known about whether such responses depend on the focus of selective attention. In this study 22 human subjects listened to concurrent, fixed-rate, speech from male and female speakers, and were asked to selectively attend to one speaker at a time, while their neural responses were recorded with MEG. The male speaker's pitch range coincided with the lower range of the high-gamma band, whereas the female speaker's higher pitch range had much less overlap, and only at the upper end of the high-gamma band. Neural responses were analyzed using the temporal response function (TRF) framework. As expected, the responses demonstrate robust speech tracking of the fundamental frequency in the high-gamma band, but only to the male's speech, with a peak latency of approximately 40 ms. Critically, the response magnitude depends on selective attention: the response to the male speech is significantly greater when male speech is attended than when it is not attended, under acoustically identical conditions. This is a clear demonstration that even very early cortical auditory responses are influenced by top-down, cognitive, neural processing mechanisms.
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Affiliation(s)
- Vrishab Commuri
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, United States
| | | | - Jonathan Z. Simon
- Department of Electrical and Computer Engineering, University of Maryland, College Park, MD, United States
- Department of Biology, University of Maryland, College Park, MD, United States
- Institute for Systems Research, University of Maryland, College Park, MD, United States
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7
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MacLean J, Stirn J, Sisson A, Bidelman GM. Short- and long-term experience-dependent neuroplasticity interact during the perceptual learning of concurrent speech. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.26.559640. [PMID: 37808665 PMCID: PMC10557636 DOI: 10.1101/2023.09.26.559640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Plasticity from auditory experiences shapes brain encoding and perception of sound. However, whether such long-term plasticity alters the trajectory of short-term plasticity during speech processing has yet to be investigated. Here, we explored the neural mechanisms and interplay between short- and long-term neuroplasticity for rapid auditory perceptual learning of concurrent speech sounds in young, normal-hearing musicians and nonmusicians. Participants learned to identify double-vowel mixtures during ∼45 minute training sessions recorded simultaneously with high-density EEG. We analyzed frequency-following responses (FFRs) and event-related potentials (ERPs) to investigate neural correlates of learning at subcortical and cortical levels, respectively. While both groups showed rapid perceptual learning, musicians showed faster behavioral decisions than nonmusicians overall. Learning-related changes were not apparent in brainstem FFRs. However, plasticity was highly evident in cortex, where ERPs revealed unique hemispheric asymmetries between groups suggestive of different neural strategies (musicians: right hemisphere bias; nonmusicians: left hemisphere). Source reconstruction and the early (150-200 ms) time course of these effects localized learning-induced cortical plasticity to auditory-sensory brain areas. Our findings confirm domain-general benefits for musicianship but reveal successful speech sound learning is driven by a critical interplay between long- and short-term mechanisms of auditory plasticity that first emerge at a cortical level.
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8
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McHaney JR, Hancock KE, Polley DB, Parthasarathy A. Sensory representations and pupil-indexed listening effort provide complementary contributions to multi-talker speech intelligibility. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.13.553131. [PMID: 37645975 PMCID: PMC10462058 DOI: 10.1101/2023.08.13.553131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Optimal speech perception in noise requires successful separation of the target speech stream from multiple competing background speech streams. The ability to segregate these competing speech streams depends on the fidelity of bottom-up neural representations of sensory information in the auditory system and top-down influences of effortful listening. Here, we use objective neurophysiological measures of bottom-up temporal processing using envelope-following responses (EFRs) to amplitude modulated tones and investigate their interactions with pupil-indexed listening effort, as it relates to performance on the Quick speech in noise (QuickSIN) test in young adult listeners with clinically normal hearing thresholds. We developed an approach using ear-canal electrodes and adjusting electrode montages for modulation rate ranges, which extended the rage of reliable EFR measurements as high as 1024Hz. Pupillary responses revealed changes in listening effort at the two most difficult signal-to-noise ratios (SNR), but behavioral deficits at the hardest SNR only. Neither pupil-indexed listening effort nor the slope of the EFR decay function independently related to QuickSIN performance. However, a linear model using the combination of EFRs and pupil metrics significantly explained variance in QuickSIN performance. These results suggest a synergistic interaction between bottom-up sensory coding and top-down measures of listening effort as it relates to speech perception in noise. These findings can inform the development of next-generation tests for hearing deficits in listeners with normal-hearing thresholds that incorporates a multi-dimensional approach to understanding speech intelligibility deficits.
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Affiliation(s)
- Jacie R. McHaney
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA
| | - Kenneth E. Hancock
- Deparment of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston MA
| | - Daniel B. Polley
- Deparment of Otolaryngology – Head and Neck Surgery, Harvard Medical School, Boston, MA
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston MA
| | - Aravindakshan Parthasarathy
- Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh PA
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9
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Carter JA, Bidelman GM. Perceptual warping exposes categorical representations for speech in human brainstem responses. Neuroimage 2023; 269:119899. [PMID: 36720437 PMCID: PMC9992300 DOI: 10.1016/j.neuroimage.2023.119899] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 01/17/2023] [Accepted: 01/22/2023] [Indexed: 01/30/2023] Open
Abstract
The brain transforms continuous acoustic events into discrete category representations to downsample the speech signal for our perceptual-cognitive systems. Such phonetic categories are highly malleable, and their percepts can change depending on surrounding stimulus context. Previous work suggests these acoustic-phonetic mapping and perceptual warping of speech emerge in the brain no earlier than auditory cortex. Here, we examined whether these auditory-category phenomena inherent to speech perception occur even earlier in the human brain, at the level of auditory brainstem. We recorded speech-evoked frequency following responses (FFRs) during a task designed to induce more/less warping of listeners' perceptual categories depending on stimulus presentation order of a speech continuum (random, forward, backward directions). We used a novel clustered stimulus paradigm to rapidly record the high trial counts needed for FFRs concurrent with active behavioral tasks. We found serial stimulus order caused perceptual shifts (hysteresis) near listeners' category boundary confirming identical speech tokens are perceived differentially depending on stimulus context. Critically, we further show neural FFRs during active (but not passive) listening are enhanced for prototypical vs. category-ambiguous tokens and are biased in the direction of listeners' phonetic label even for acoustically-identical speech stimuli. These findings were not observed in the stimulus acoustics nor model FFR responses generated via a computational model of cochlear and auditory nerve transduction, confirming a central origin to the effects. Our data reveal FFRs carry category-level information and suggest top-down processing actively shapes the neural encoding and categorization of speech at subcortical levels. These findings suggest the acoustic-phonetic mapping and perceptual warping in speech perception occur surprisingly early along the auditory neuroaxis, which might aid understanding by reducing ambiguity inherent to the speech signal.
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Affiliation(s)
- Jared A Carter
- Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences and Disorders, University of Memphis, Memphis, TN, USA; Division of Clinical Neuroscience, School of Medicine, Hearing Sciences - Scottish Section, University of Nottingham, Glasgow, Scotland, UK
| | - Gavin M Bidelman
- Department of Speech, Language and Hearing Sciences, Indiana University, Bloomington, IN, USA; Program in Neuroscience, Indiana University, Bloomington, IN, USA.
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10
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Guérit F, Harland AJ, Richardson ML, Gransier R, Middlebrooks JC, Wouters J, Carlyon RP. Electrophysiological and Psychophysical Measures of Temporal Pitch Sensitivity in Normal-hearing Listeners. J Assoc Res Otolaryngol 2023; 24:47-65. [PMID: 36471208 PMCID: PMC9971391 DOI: 10.1007/s10162-022-00879-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 11/17/2022] [Indexed: 12/12/2022] Open
Abstract
To obtain combined behavioural and electrophysiological measures of pitch perception, we presented harmonic complexes, bandpass filtered to contain only high-numbered harmonics, to normal-hearing listeners. These stimuli resemble bandlimited pulse trains and convey pitch using a purely temporal code. A core set of conditions consisted of six stimuli with baseline pulse rates of 94, 188 and 280 pps, filtered into a HIGH (3365-4755 Hz) or VHIGH (7800-10,800 Hz) region, alternating with a 36% higher pulse rate. Brainstem and cortical processing were measured using the frequency following response (FFR) and auditory change complex (ACC), respectively. Behavioural rate change difference limens (DLs) were measured by requiring participants to discriminate between a stimulus that changed rate twice (up-down or down-up) during its 750-ms presentation from a constant-rate pulse train. FFRs revealed robust brainstem phase locking whose amplitude decreased with increasing rate. Moderate-sized but reliable ACCs were obtained in response to changes in purely temporal pitch and, like the psychophysical DLs, did not depend consistently on the direction of rate change or on the pulse rate for baseline rates between 94 and 280 pps. ACCs were larger and DLs lower for stimuli in the HIGH than in the VHGH region. We argue that the ACC may be a useful surrogate for behavioural measures of rate discrimination, both for normal-hearing listeners and for cochlear-implant users. We also showed that rate DLs increased markedly when the baseline rate was reduced to 48 pps, and compared the behavioural and electrophysiological findings to recent cat data obtained with similar stimuli and methods.
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Affiliation(s)
- François Guérit
- Cambridge Hearing Group, MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, England
| | - Andrew J Harland
- Cambridge Hearing Group, MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, England
| | - Matthew L Richardson
- Department of Otolaryngology, University of California at Irvine, Irvine, CA, USA
| | | | - John C Middlebrooks
- Department of Otolaryngology, University of California at Irvine, Irvine, CA, USA
- Department of Neurobiology and Behavior, University of California at Irvine, Irvine, CA, USA
- Department of Cognitive Sciences, University o f California at Irvine, Irvine, CA, USA
- Department of Biomedical Engineering, University of California at Irvine, Irvine, CA, USA
| | - Jan Wouters
- Department of Neurosciences, ExpORL, Leuven, Belgium
| | - Robert P Carlyon
- Cambridge Hearing Group, MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, England.
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11
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Kumar S, Nayak S, Pitchai Muthu AN. Effect of selective attention on auditory brainstem response. HEARING, BALANCE AND COMMUNICATION 2023. [DOI: 10.1080/21695717.2023.2168413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Sathish Kumar
- Department of Audiology and Speech-Language Pathology, Kasturba Medical College, Mangalore, Manipal Academy of Higher Education, Mangalore, India
| | - Srikanth Nayak
- Department of Audiology and Speech-Language Pathology, Yenepoya Medical College, Yenepoya University (Deemed to be University), Mangalore, India
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12
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Mesik J, Wojtczak M. The effects of data quantity on performance of temporal response function analyses of natural speech processing. Front Neurosci 2023; 16:963629. [PMID: 36711133 PMCID: PMC9878558 DOI: 10.3389/fnins.2022.963629] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 12/26/2022] [Indexed: 01/15/2023] Open
Abstract
In recent years, temporal response function (TRF) analyses of neural activity recordings evoked by continuous naturalistic stimuli have become increasingly popular for characterizing response properties within the auditory hierarchy. However, despite this rise in TRF usage, relatively few educational resources for these tools exist. Here we use a dual-talker continuous speech paradigm to demonstrate how a key parameter of experimental design, the quantity of acquired data, influences TRF analyses fit to either individual data (subject-specific analyses), or group data (generic analyses). We show that although model prediction accuracy increases monotonically with data quantity, the amount of data required to achieve significant prediction accuracies can vary substantially based on whether the fitted model contains densely (e.g., acoustic envelope) or sparsely (e.g., lexical surprisal) spaced features, especially when the goal of the analyses is to capture the aspect of neural responses uniquely explained by specific features. Moreover, we demonstrate that generic models can exhibit high performance on small amounts of test data (2-8 min), if they are trained on a sufficiently large data set. As such, they may be particularly useful for clinical and multi-task study designs with limited recording time. Finally, we show that the regularization procedure used in fitting TRF models can interact with the quantity of data used to fit the models, with larger training quantities resulting in systematically larger TRF amplitudes. Together, demonstrations in this work should aid new users of TRF analyses, and in combination with other tools, such as piloting and power analyses, may serve as a detailed reference for choosing acquisition duration in future studies.
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Van Der Biest H, Keshishzadeh S, Keppler H, Dhooge I, Verhulst S. Envelope following responses for hearing diagnosis: Robustness and methodological considerations. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:191. [PMID: 36732231 DOI: 10.1121/10.0016807] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 12/19/2022] [Indexed: 06/18/2023]
Abstract
Recent studies have found that envelope following responses (EFRs) are a marker of age-related and noise- or ototoxic-induced cochlear synaptopathy (CS) in research animals. Whereas the cochlear injury can be well controlled in animal research studies, humans may have an unknown mixture of sensorineural hearing loss [SNHL; e.g., inner- or outer-hair-cell (OHC) damage or CS] that cannot be teased apart in a standard hearing evaluation. Hence, a direct translation of EFR markers of CS to a differential CS diagnosis in humans might be compromised by the influence of SNHL subtypes and differences in recording modalities between research animals and humans. To quantify the robustness of EFR markers for use in human studies, this study investigates the impact of methodological considerations related to electrode montage, stimulus characteristics, and presentation, as well as analysis method on human-recorded EFR markers. The main focus is on rectangularly modulated pure-tone stimuli to evoke the EFR based on a recent auditory modelling study that showed that the EFR was least affected by OHC damage and most sensitive to CS in this stimulus configuration. The outcomes of this study can help guide future clinical implementations of electroencephalography-based SNHL diagnostic tests.
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Affiliation(s)
- Heleen Van Der Biest
- Hearing Technology at Wireless, Acoustics, Environment and Expert Systems, Department of Information Technology, Ghent, Belgium
| | - Sarineh Keshishzadeh
- Hearing Technology at Wireless, Acoustics, Environment and Expert Systems, Department of Information Technology, Ghent, Belgium
| | - Hannah Keppler
- Department of Rehabilitation Sciences-Audiology, Ghent University, Ghent, Belgium
| | - Ingeborg Dhooge
- Department of Head and Skin, Ghent University, Ghent, Belgium
| | - Sarah Verhulst
- Hearing Technology at Wireless, Acoustics, Environment and Expert Systems, Department of Information Technology, Ghent, Belgium
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14
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Simon JZ, Commuri V, Kulasingham JP. Time-locked auditory cortical responses in the high-gamma band: A window into primary auditory cortex. Front Neurosci 2022; 16:1075369. [PMID: 36570848 PMCID: PMC9773383 DOI: 10.3389/fnins.2022.1075369] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 11/24/2022] [Indexed: 12/13/2022] Open
Abstract
Primary auditory cortex is a critical stage in the human auditory pathway, a gateway between subcortical and higher-level cortical areas. Receiving the output of all subcortical processing, it sends its output on to higher-level cortex. Non-invasive physiological recordings of primary auditory cortex using electroencephalography (EEG) and magnetoencephalography (MEG), however, may not have sufficient specificity to separate responses generated in primary auditory cortex from those generated in underlying subcortical areas or neighboring cortical areas. This limitation is important for investigations of effects of top-down processing (e.g., selective-attention-based) on primary auditory cortex: higher-level areas are known to be strongly influenced by top-down processes, but subcortical areas are often assumed to perform strictly bottom-up processing. Fortunately, recent advances have made it easier to isolate the neural activity of primary auditory cortex from other areas. In this perspective, we focus on time-locked responses to stimulus features in the high gamma band (70-150 Hz) and with early cortical latency (∼40 ms), intermediate between subcortical and higher-level areas. We review recent findings from physiological studies employing either repeated simple sounds or continuous speech, obtaining either a frequency following response (FFR) or temporal response function (TRF). The potential roles of top-down processing are underscored, and comparisons with invasive intracranial EEG (iEEG) and animal model recordings are made. We argue that MEG studies employing continuous speech stimuli may offer particular benefits, in that only a few minutes of speech generates robust high gamma responses from bilateral primary auditory cortex, and without measurable interference from subcortical or higher-level areas.
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Affiliation(s)
- Jonathan Z. Simon
- Department of Electrical and Computer Engineering, University of Maryland, College Park, College Park, MD, United States,Department of Biology, University of Maryland, College Park, College Park, MD, United States,Institute for Systems Research, University of Maryland, College Park, College Park, MD, United States,*Correspondence: Jonathan Z. Simon,
| | - Vrishab Commuri
- Department of Electrical and Computer Engineering, University of Maryland, College Park, College Park, MD, United States
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15
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Lu H, Mehta AH, Oxenham AJ. Methodological considerations when measuring and analyzing auditory steady-state responses with multi-channel EEG. CURRENT RESEARCH IN NEUROBIOLOGY 2022; 3:100061. [PMID: 36386860 PMCID: PMC9647176 DOI: 10.1016/j.crneur.2022.100061] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 07/11/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022] Open
Abstract
The auditory steady-state response (ASSR) has been traditionally recorded with few electrodes and is often measured as the voltage difference between mastoid and vertex electrodes (vertical montage). As high-density EEG recording systems have gained popularity, multi-channel analysis methods have been developed to integrate the ASSR signal across channels. The phases of ASSR across electrodes can be affected by factors including the stimulus modulation rate and re-referencing strategy, which will in turn affect the estimated ASSR strength. To explore the relationship between the classical vertical-montage ASSR and whole-scalp ASSR, we applied these two techniques to the same data to estimate the strength of ASSRs evoked by tones with sinusoidal amplitude modulation rates of around 40, 100, and 200 Hz. The whole-scalp methods evaluated in our study, with either linked-mastoid or common-average reference, included ones that assume equal phase across all channels, as well as ones that allow for different phase relationships. The performance of simple averaging was compared to that of more complex methods involving principal component analysis. Overall, the root-mean-square of the phase locking values (PLVs) across all channels provided the most efficient method to detect ASSR across the range of modulation rates tested here.
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Affiliation(s)
- Hao Lu
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, MN, 55455, USA
| | - Anahita H. Mehta
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, MN, 55455, USA
| | - Andrew J. Oxenham
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, MN, 55455, USA
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16
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Lai J, Price CN, Bidelman GM. Brainstem speech encoding is dynamically shaped online by fluctuations in cortical α state. Neuroimage 2022; 263:119627. [PMID: 36122686 PMCID: PMC10017375 DOI: 10.1016/j.neuroimage.2022.119627] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 09/12/2022] [Indexed: 11/25/2022] Open
Abstract
Experimental evidence in animals demonstrates cortical neurons innervate subcortex bilaterally to tune brainstem auditory coding. Yet, the role of the descending (corticofugal) auditory system in modulating earlier sound processing in humans during speech perception remains unclear. Here, we measured EEG activity as listeners performed speech identification tasks in different noise backgrounds designed to tax perceptual and attentional processing. We hypothesized brainstem speech coding might be tied to attention and arousal states (indexed by cortical α power) that actively modulate the interplay of brainstem-cortical signal processing. When speech-evoked brainstem frequency-following responses (FFRs) were categorized according to cortical α states, we found low α FFRs in noise were weaker, correlated positively with behavioral response times, and were more "decodable" via neural classifiers. Our data provide new evidence for online corticofugal interplay in humans and establish that brainstem sensory representations are continuously yoked to (i.e., modulated by) the ebb and flow of cortical states to dynamically update perceptual processing.
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Affiliation(s)
- Jesyin Lai
- Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences and Disorders, University of Memphis, Memphis, TN, USA; Diagnostic Imaging Department, St. Jude Children's Research Hospital, Memphis, TN, USA.
| | - Caitlin N Price
- Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences and Disorders, University of Memphis, Memphis, TN, USA; Department of Audiology and Speech Pathology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Gavin M Bidelman
- Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences and Disorders, University of Memphis, Memphis, TN, USA; Department of Speech, Language and Hearing Sciences, Indiana University, 2631 East Discovery Parkway, Bloomington, IN 47408, USA; Program in Neuroscience, Indiana University, 1101 E 10th St, Bloomington, IN 47405, USA.
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17
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Characteristics of the Deconvolved Transient AEP from 80 Hz Steady-State Responses to Amplitude Modulation Stimulation. J Assoc Res Otolaryngol 2021; 22:741-753. [PMID: 34415469 DOI: 10.1007/s10162-021-00806-2] [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: 11/23/2020] [Accepted: 07/02/2021] [Indexed: 10/20/2022] Open
Abstract
This study aimed to validate the existence and investigate the characteristics of the transient responses from conventional auditory steady-state responses (ASSRs) using deconvolution methods capable of dealing with amplitude modulated (AM) stimulation. Conventional ASSRs to seven stimulus rates were recorded from 17 participants. A deconvolution method was selected and modified to accommodate the AM stimulation. The calculated responses were examined in terms of temporal features with respect to different combinations of stimulus rates. Stable transient responses consisting of early stage brainstem responses and middle latency responses were reconstructed consistently for all rate combinations, which indicates that the superposition hypothesis is applicable to the generation of approximately 80 Hz ASSRs evoked by AM tones (AM-ASSRs). The new transient responses are characterized by three pairs of peak-troughs named as n0p0, n1p1, and n2p2 within 40 ms. Compared with conventional ABR-MLRs, the n0p0 indicates the first neural activity where p0 might represent the main ABR components; the n1 is the counterpart of N10; the p2 is corresponding to the robust Pa at about 30 ms; the p1 and n2 are absent of real counterparts. The peak-peak amplitudes show a slight decrease with increasing stimulation rate from 75 to 95 Hz whereas the peak latencies change differently, which is consistent with the known rate-effect on AEPs. This is direct evidence for a transient response derived from AM-ASSRs for the first time. The characteristic components offer insight into the constitution of AM-ASSRs and may be promising in clinical applications and fundamental studies.
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18
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Abstract
The perception of sensory events can be enhanced or suppressed by the surrounding spatial and temporal context in ways that facilitate the detection of novel objects and contribute to the perceptual constancy of those objects under variable conditions. In the auditory system, the phenomenon known as auditory enhancement reflects a general principle of contrast enhancement, in which a target sound embedded within a background sound becomes perceptually more salient if the background is presented first by itself. This effect is highly robust, producing an effective enhancement of the target of up to 25 dB (more than two orders of magnitude in intensity), depending on the task. Despite the importance of the effect, neural correlates of auditory contrast enhancement have yet to be identified in humans. Here, we used the auditory steady-state response to probe the neural representation of a target sound under conditions of enhancement. The probe was simultaneously modulated in amplitude with two modulation frequencies to distinguish cortical from subcortical responses. We found robust correlates for neural enhancement in the auditory cortical, but not subcortical, responses. Our findings provide empirical support for a previously unverified theory of auditory enhancement based on neural adaptation of inhibition and point to approaches for improving sensory prostheses for hearing loss, such as hearing aids and cochlear implants.
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Affiliation(s)
- Anahita H Mehta
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455
| | - Lei Feng
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455
| | - Andrew J Oxenham
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455
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19
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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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20
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Gransier R, Guérit F, Carlyon RP, Wouters J. Frequency following responses and rate change complexes in cochlear implant users. Hear Res 2021; 404:108200. [PMID: 33647574 PMCID: PMC8052190 DOI: 10.1016/j.heares.2021.108200] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 01/25/2021] [Accepted: 02/06/2021] [Indexed: 01/05/2023]
Abstract
The upper limit of rate-based pitch perception and rate discrimination can differ substantially across cochlear implant (CI) users. One potential reason for this difference is the presence of a biological limitation on temporal encoding in the electrically-stimulated auditory pathway, which can be inherent to the electrical stimulation itself and/or to the degenerative processes associated with hearing loss. Electrophysiological measures, like the electrically-evoked frequency following response (eFFR) and auditory change complex (eACC), could potentially provide valuable insights in the temporal processing limitations at the level of the brainstem and cortex in the electrically-stimulated auditory pathway. Obtaining these neural responses, free from stimulation artifacts, is challenging, especially when the neural response is phase-locked to the stimulation rate, as is the case for the eFFR. In this study we investigated the feasibility of measuring eFFRs, free from stimulation artifacts, to stimulation rates ranging from 94 to 196 pulses per second (pps) and eACCs to pulse rate changes ranging from 36 to 108%, when stimulating in a monopolar configuration. A high-sampling rate EEG system was used to measure the electrophysiological responses in five CI users, and linear interpolation was applied to remove the stimulation artifacts from the EEG. With this approach, we were able to measure eFFRs for pulse rates up to 162 pps and eACCs to the different rate changes. Our results show that it is feasible to measure electrophysiological responses, free from stimulation artifacts, that could potentially be used as neural correlates for rate and pitch processing in CI users.
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Affiliation(s)
- Robin Gransier
- KU Leuven, Department of Neurosciences, ExpORL, Herestraat 49, Box 721, Leuven 3000, Belgium.
| | - Franҫois Guérit
- Cambridge Hearing Group, MRC Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge CB2 7EF, United Kingdom
| | - Robert P Carlyon
- Cambridge Hearing Group, MRC Cognition and Brain Sciences Unit, University of Cambridge, 15 Chaucer Road, Cambridge CB2 7EF, United Kingdom
| | - Jan Wouters
- KU Leuven, Department of Neurosciences, ExpORL, Herestraat 49, Box 721, Leuven 3000, Belgium
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21
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Van Canneyt J, Wouters J, Francart T. Neural tracking of the fundamental frequency of the voice: The effect of voice characteristics. Eur J Neurosci 2021; 53:3640-3653. [DOI: 10.1111/ejn.15229] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/24/2021] [Accepted: 04/08/2021] [Indexed: 11/26/2022]
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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22
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Price CN, Bidelman GM. Attention reinforces human corticofugal system to aid speech perception in noise. Neuroimage 2021; 235:118014. [PMID: 33794356 PMCID: PMC8274701 DOI: 10.1016/j.neuroimage.2021.118014] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/09/2021] [Accepted: 03/25/2021] [Indexed: 12/13/2022] Open
Abstract
Perceiving speech-in-noise (SIN) demands precise neural coding between brainstem and cortical levels of the hearing system. Attentional processes can then select and prioritize task-relevant cues over competing background noise for successful speech perception. In animal models, brainstem-cortical interplay is achieved via descending corticofugal projections from cortex that shape midbrain responses to behaviorally-relevant sounds. Attentional engagement of corticofugal feedback may assist SIN understanding but has never been confirmed and remains highly controversial in humans. To resolve these issues, we recorded source-level, anatomically constrained brainstem frequency-following responses (FFRs) and cortical event-related potentials (ERPs) to speech via high-density EEG while listeners performed rapid SIN identification tasks. We varied attention with active vs. passive listening scenarios whereas task difficulty was manipulated with additive noise interference. Active listening (but not arousal-control tasks) exaggerated both ERPs and FFRs, confirming attentional gain extends to lower subcortical levels of speech processing. We used functional connectivity to measure the directed strength of coupling between levels and characterize "bottom-up" vs. "top-down" (corticofugal) signaling within the auditory brainstem-cortical pathway. While attention strengthened connectivity bidirectionally, corticofugal transmission disengaged under passive (but not active) SIN listening. Our findings (i) show attention enhances the brain's transcription of speech even prior to cortex and (ii) establish a direct role of the human corticofugal feedback system as an aid to cocktail party speech perception.
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Affiliation(s)
- Caitlin N Price
- Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences and Disorders, University of Memphis, 4055 North Park Loop, Memphis, TN 38152, USA.
| | - Gavin M Bidelman
- Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences and Disorders, University of Memphis, 4055 North Park Loop, Memphis, TN 38152, USA; Department of Anatomy and Neurobiology, University of Tennessee Health Sciences Center, Memphis, TN, USA.
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23
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Defining the Role of Attention in Hierarchical Auditory Processing. Audiol Res 2021; 11:112-128. [PMID: 33805600 PMCID: PMC8006147 DOI: 10.3390/audiolres11010012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/07/2021] [Accepted: 03/10/2021] [Indexed: 01/09/2023] Open
Abstract
Communication in noise is a complex process requiring efficient neural encoding throughout the entire auditory pathway as well as contributions from higher-order cognitive processes (i.e., attention) to extract speech cues for perception. Thus, identifying effective clinical interventions for individuals with speech-in-noise deficits relies on the disentanglement of bottom-up (sensory) and top-down (cognitive) factors to appropriately determine the area of deficit; yet, how attention may interact with early encoding of sensory inputs remains unclear. For decades, attentional theorists have attempted to address this question with cleverly designed behavioral studies, but the neural processes and interactions underlying attention's role in speech perception remain unresolved. While anatomical and electrophysiological studies have investigated the neurological structures contributing to attentional processes and revealed relevant brain-behavior relationships, recent electrophysiological techniques (i.e., simultaneous recording of brainstem and cortical responses) may provide novel insight regarding the relationship between early sensory processing and top-down attentional influences. In this article, we review relevant theories that guide our present understanding of attentional processes, discuss current electrophysiological evidence of attentional involvement in auditory processing across subcortical and cortical levels, and propose areas for future study that will inform the development of more targeted and effective clinical interventions for individuals with speech-in-noise deficits.
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24
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Neural generators of the frequency-following response elicited to stimuli of low and high frequency: A magnetoencephalographic (MEG) study. Neuroimage 2021; 231:117866. [PMID: 33592244 DOI: 10.1016/j.neuroimage.2021.117866] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 01/03/2023] Open
Abstract
The frequency-following response (FFR) to periodic complex sounds has gained recent interest in auditory cognitive neuroscience as it captures with great fidelity the tracking accuracy of the periodic sound features in the ascending auditory system. Seminal studies suggested the FFR as a correlate of subcortical sound encoding, yet recent studies aiming to locate its sources challenged this assumption, demonstrating that FFR receives some contribution from the auditory cortex. Based on frequency-specific phase-locking capabilities along the auditory hierarchy, we hypothesized that FFRs to higher frequencies would receive less cortical contribution than those to lower frequencies, hence supporting a major subcortical involvement for these high frequency sounds. Here, we used a magnetoencephalographic (MEG) approach to trace the neural sources of the FFR elicited in healthy adults (N = 19) to low (89 Hz) and high (333 Hz) frequency sounds. FFRs elicited to the high and low frequency sounds were clearly observable on MEG and comparable to those obtained in simultaneous electroencephalographic recordings. Distributed source modeling analyses revealed midbrain, thalamic, and cortical contributions to FFR, arranged in frequency-specific configurations. Our results showed that the main contribution to the high-frequency sound FFR originated in the inferior colliculus and the medial geniculate body of the thalamus, with no significant cortical contribution. In contrast, the low-frequency sound FFR had a major contribution located in the auditory cortices, and also received contributions originating in the midbrain and thalamic structures. These findings support the multiple generator hypothesis of the FFR and are relevant for our understanding of the neural encoding of sounds along the auditory hierarchy, suggesting a hierarchical organization of periodicity encoding.
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25
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White-Schwoch T, Krizman J, Nicol T, Kraus N. Case studies in neuroscience: cortical contributions to the frequency-following response depend on subcortical synchrony. J Neurophysiol 2020; 125:273-281. [PMID: 33206575 DOI: 10.1152/jn.00104.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Frequency-following responses to musical notes spanning the octave 65-130 Hz were elicited in a person with auditory neuropathy, a disorder of subcortical neural synchrony, and a control subject. No phaselocked responses were observed in the person with auditory neuropathy. The control subject had robust responses synchronized to the fundamental frequency and its harmonics. Cortical onset responses to each note in the series were present in both subjects. These results support the hypothesis that subcortical neural synchrony is necessary to generate the frequency-following response-including for stimulus frequencies at which a cortical contribution has been noted. Although auditory cortex ensembles may synchronize to fundamental frequency cues in speech and music, subcortical neural synchrony appears to be a necessary antecedent.NEW & NOTEWORTHY A listener with auditory neuropathy, an absence of subcortical neural synchrony, did not have electrophysiological frequency-following responses synchronized to an octave of musical notes, with fundamental frequencies ranging from 65 to 130 Hz. A control subject had robust responses that phaselocked to each note. Although auditory cortex may contribute to the scalp-recorded frequency-following response in healthy listeners, our results suggest this phenomenon depends on subcortical neural synchrony.
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Affiliation(s)
- Travis White-Schwoch
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, Evanston, Illinois
| | - Jennifer Krizman
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, Evanston, Illinois
| | - Trent Nicol
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, Evanston, Illinois
| | - Nina Kraus
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, Evanston, Illinois.,Departments of Neurobiology and Otolaryngology, Northwestern University, Evanston, Illinois
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26
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Speech frequency-following response in human auditory cortex is more than a simple tracking. Neuroimage 2020; 226:117545. [PMID: 33186711 DOI: 10.1016/j.neuroimage.2020.117545] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 11/20/2022] Open
Abstract
The human auditory cortex is recently found to contribute to the frequency following response (FFR) and the cortical component has been shown to be more relevant to speech perception. However, it is not clear how cortical FFR may contribute to the processing of speech fundamental frequency (F0) and the dynamic pitch. Using intracranial EEG recordings, we observed a significant FFR at the fundamental frequency (F0) for both speech and speech-like harmonic complex stimuli in the human auditory cortex, even in the missing fundamental condition. Both the spectral amplitude and phase coherence of the cortical FFR showed a significant harmonic preference, and attenuated from the primary auditory cortex to the surrounding associative auditory cortex. The phase coherence of the speech FFR was found significantly higher than that of the harmonic complex stimuli, especially in the left hemisphere, showing a high timing fidelity of the cortical FFR in tracking dynamic F0 in speech. Spectrally, the frequency band of the cortical FFR was largely overlapped with the range of the human vocal pitch. Taken together, our study parsed the intrinsic properties of the cortical FFR and reveals a preference for speech-like sounds, supporting its potential role in processing speech intonation and lexical tones.
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27
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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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28
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Van Canneyt J, Wouters J, Francart T. From modulated noise to natural speech: The effect of stimulus parameters on the envelope following response. Hear Res 2020; 393:107993. [PMID: 32535277 DOI: 10.1016/j.heares.2020.107993] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 04/28/2020] [Accepted: 05/04/2020] [Indexed: 11/28/2022]
Abstract
Envelope following responses (EFRs) can be evoked by a wide range of auditory stimuli, but for many stimulus parameters the effect on EFR strength is not fully understood. This complicates the comparison of earlier studies and the design of new studies. Furthermore, the most optimal stimulus parameters are unknown. To help resolve this issue, we investigated the effects of four important stimulus parameters and their interactions on the EFR. Responses were measured in 16 normal hearing subjects evoked by stimuli with four levels of stimulus complexity (amplitude modulated noise, artificial vowels, natural vowels and vowel-consonant-vowel combinations), three fundamental frequencies (105 Hz, 185 Hz and 245 Hz), three fundamental frequency contours (upward sweeping, downward sweeping and flat) and three vowel identities (Flemish /a:/, /u:/, and /i:/). We found that EFRs evoked by artificial vowels were on average 4-6 dB SNR larger than responses evoked by the other stimulus complexities, probably because of (unnaturally) strong higher harmonics. Moreover, response amplitude decreased with fundamental frequency but response SNR remained largely unaffected. Thirdly, fundamental frequency variation within the stimulus did not impact EFR strength, but only when rate of change remained low (e.g. not the case for sweeping natural vowels). Finally, the vowel /i:/ appeared to evoke larger response amplitudes compared to /a:/ and /u:/, but analysis power was too small to confirm this statistically. Vowel-dependent differences in response strength have been suggested to stem from destructive interference between response components. We show how a model of the auditory periphery can simulate these interference patterns and predict response strength. Altogether, the results of this study can guide stimulus choice for future EFR research and practical applications.
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Affiliation(s)
- Jana Van Canneyt
- ExpORL, Dept. of Neurosciences, KU Leuven, Herestraat 49 Bus 721, 3000, Leuven, Belgium.
| | - Jan Wouters
- ExpORL, Dept. of Neurosciences, KU Leuven, Herestraat 49 Bus 721, 3000, Leuven, Belgium.
| | - Tom Francart
- ExpORL, Dept. of Neurosciences, KU Leuven, Herestraat 49 Bus 721, 3000, Leuven, Belgium.
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Tepe V, Papesh M, Russell S, Lewis MS, Pryor N, Guillory L. Acquired Central Auditory Processing Disorder in Service Members and Veterans. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2020; 63:834-857. [PMID: 32163310 DOI: 10.1044/2019_jslhr-19-00293] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Purpose A growing body of evidence suggests that military service members and military veterans are at risk for deficits in central auditory processing. Risk factors include exposure to blast, neurotrauma, hazardous noise, and ototoxicants. We overview these risk factors and comorbidities, address implications for clinical assessment and care of central auditory processing deficits in service members and veterans, and specify knowledge gaps that warrant research. Method We reviewed the literature to identify studies of risk factors, assessment, and care of central auditory processing deficits in service members and veterans. We also assessed the current state of the science for knowledge gaps that warrant additional study. This literature review describes key findings relating to military risk factors and clinical considerations for the assessment and care of those exposed. Conclusions Central auditory processing deficits are associated with exposure to known military risk factors. Research is needed to characterize mechanisms, sources of variance, and differential diagnosis in this population. Existing best practices do not explicitly consider confounds faced by military personnel. Assessment and rehabilitation strategies that account for these challenges are needed. Finally, investment is critical to ensure that Veterans Affairs and Department of Defense clinical staff are informed, trained, and equipped to implement effective patient care.
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Affiliation(s)
- Victoria Tepe
- Department of Defense Hearing Center of Excellence, JBSA Lackland, TX
- The Geneva Foundation, Tacoma, WA
| | - Melissa Papesh
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
- Department of Otolaryngology-Head & Neck Surgery, Oregon Health & Science University, Portland
| | - Shoshannah Russell
- Walter Reed National Military Medical Center, Bethesda, MD
- Henry Jackson Foundation, Bethesda, MD
| | - M Samantha Lewis
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
- Department of Otolaryngology-Head & Neck Surgery, Oregon Health & Science University, Portland
- School of Audiology, Pacific University, Hillsboro, OR
| | - Nina Pryor
- Department of Defense Hearing Center of Excellence, JBSA Lackland, TX
- Air Force Research Laboratory, Wright-Patterson Air Force Base, OH
| | - Lisa Guillory
- Harry S. Truman Memorial Veterans' Hospital, Columbia, MO
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Missouri, Columbia
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Rouhbakhsh N, Mahdi J, Hwo J, Nobel B, Mousave F. Human Frequency Following Response Correlates of Spatial Release From Masking. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2019; 62:4165-4178. [PMID: 31644365 DOI: 10.1044/2019_jslhr-h-18-0353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Purpose Speech recognition in complex listening environments is enhanced by the extent of spatial separation between the speech source and background competing sources, an effect known as spatial release from masking (SRM). The aim of this study was to investigate whether the phase-locked neural activity in the central auditory pathways, reflected in the frequency following response (FFR), exhibits SRM. Method Eighteen normal-hearing adults (8 men and 10 women, ranging in age from 20 to 42 years) with no known neurological disorders participated in this study. FFRs were recorded from the participants in response to a target vowel /u/ presented with spatially colocated and separated competing talkers at 3 ranges of signal-to-noise ratios (SNRs), with median SNRs of -5.4, 0.5, and 6.8 dB and for different attentional conditions (attention and no attention). Results Amplitude of the FFR at the fundamental frequency was significantly larger in the spatially separated condition as compared to the colocated condition for only the lowest (< -2.4 dB SNR) of the 3 SNR ranges tested. A significant effect of attention was found when subjects were actively focusing on the target stimuli. No significant interaction effects were found between spatial separation and attention. Conclusions The enhanced representation of the target stimulus in the separated condition suggests that the temporal pattern of phase-locked brainstem neural activity generating the FFR may contain information relevant to the binaural processes underlying SRM but only in challenging listening environments. Attention may modulate FFR fundamental frequency amplitude but does not seem to modulate spatial processing at the level of generating the FFR. Supplemental Material https://doi.org/10.23641/asha.9992597.
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Affiliation(s)
- Nematollah Rouhbakhsh
- HEARing Cooperation Research Centre, Melbourne, Victoria, Australia
- University of Melbourne, Victoria, Australia
- National Acoustic Laboratories, Australian Hearing Hub, Macquarie University, Sydney, New South Wales, Australia
- Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Iran
| | - John Mahdi
- The New York Academy of Sciences, New York
| | - Jacob Hwo
- Faculty of Medicine and Health, Department of Biomedical Science, The University of Sydney, New South Wales, Australia
| | - Baran Nobel
- Department of Audiology, School of Health and Rehabilitation Sciences, The University of Queensland, St. Lucia, Australia
| | - Fati Mousave
- Department of Audiology, School of Health and Rehabilitation Sciences, The University of Queensland, St. Lucia, Australia
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Coffey EBJ, Nicol T, White-Schwoch T, Chandrasekaran B, Krizman J, Skoe E, Zatorre RJ, Kraus N. Evolving perspectives on the sources of the frequency-following response. Nat Commun 2019; 10:5036. [PMID: 31695046 PMCID: PMC6834633 DOI: 10.1038/s41467-019-13003-w] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 10/14/2019] [Indexed: 11/09/2022] Open
Abstract
The auditory frequency-following response (FFR) is a non-invasive index of the fidelity of sound encoding in the brain, and is used to study the integrity, plasticity, and behavioral relevance of the neural encoding of sound. In this Perspective, we review recent evidence suggesting that, in humans, the FFR arises from multiple cortical and subcortical sources, not just subcortically as previously believed, and we illustrate how the FFR to complex sounds can enhance the wider field of auditory neuroscience. Far from being of use only to study basic auditory processes, the FFR is an uncommonly multifaceted response yielding a wealth of information, with much yet to be tapped.
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Affiliation(s)
- Emily B J Coffey
- Department of Psychology, Concordia University, 1455 Boulevard de Maisonneuve Ouest, Montréal, QC, H3G 1M8, Canada.
- International Laboratory for Brain, Music, and Sound Research (BRAMS), Montréal, QC, Canada.
- Centre for Research on Brain, Language and Music (CRBLM), McGill University, 3640 de la Montagne, Montréal, QC, H3G 2A8, Canada.
| | - Trent Nicol
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, 2240 Campus Dr., Evanston, IL, 60208, USA
| | - Travis White-Schwoch
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, 2240 Campus Dr., Evanston, IL, 60208, USA
| | - Bharath Chandrasekaran
- Communication Sciences and Disorders, School of Health and Rehabilitation Sciences, University of Pittsburgh, Forbes Tower, 3600 Atwood St, Pittsburgh, PA, 15260, USA
| | - Jennifer Krizman
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, 2240 Campus Dr., Evanston, IL, 60208, USA
| | - Erika Skoe
- Department of Speech, Language, and Hearing Sciences, The Connecticut Institute for the Brain and Cognitive Sciences, University of Connecticut, 2 Alethia Drive, Unit 1085, Storrs, CT, 06269, USA
| | - Robert J Zatorre
- International Laboratory for Brain, Music, and Sound Research (BRAMS), Montréal, QC, Canada
- Centre for Research on Brain, Language and Music (CRBLM), McGill University, 3640 de la Montagne, Montréal, QC, H3G 2A8, Canada
- Montreal Neurological Institute, McGill University, 3801 rue Université, Montréal, QC, H3A 2B4, Canada
| | - Nina Kraus
- Auditory Neuroscience Laboratory, Department of Communication Sciences, Northwestern University, 2240 Campus Dr., Evanston, IL, 60208, USA
- Department of Neurobiology, Northwestern University, 2205 Tech Dr., Evanston, IL, 60208, USA
- Department of Otolaryngology, Northwestern University, 420 E Superior St., Chicago, IL, 6011, USA
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32
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Hartmann T, Weisz N. Auditory cortical generators of the Frequency Following Response are modulated by intermodal attention. Neuroimage 2019; 203:116185. [PMID: 31520743 DOI: 10.1016/j.neuroimage.2019.116185] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/03/2019] [Accepted: 09/10/2019] [Indexed: 11/20/2022] Open
Abstract
The efferent auditory system suggests that brainstem auditory regions could also be sensitive to top-down processes. In electrophysiology, the Frequency Following Response (FFR) to speech stimuli has been used extensively to study brainstem areas. Despite seemingly straight-forward in addressing the issue of attentional modulations of brainstem regions by means of the FFR, the existing results are inconsistent. Moreover, the notion that the FFR exclusively represents subcortical generators has been challenged. We aimed to gain a more differentiated perspective on how the generators of the FFR are modulated by either attending to the visual or auditory input while neural activity was recorded using magnetoencephalography (MEG). In a first step our results confirm the strong contribution of also cortical regions to the FFR. Interestingly, of all regions exhibiting a measurable FFR response, only the right primary auditory cortex was significantly affected by intermodal attention. By showing a clear cortical contribution to the attentional FFR effect, our work significantly extends previous reports that focus on surface level recordings only. It underlines the importance of making a greater effort to disentangle the different contributing sources of the FFR and serves as a clear precaution of simplistically interpreting the FFR as brainstem response.
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Affiliation(s)
- Thomas Hartmann
- Centre for Cognitive Neuroscience and Department of Psychology, Paris-Lodron Universität Salzburg, Hellbrunnerstraße 34/II, 5020, Salzburg, Austria.
| | - Nathan Weisz
- Centre for Cognitive Neuroscience and Department of Psychology, Paris-Lodron Universität Salzburg, Hellbrunnerstraße 34/II, 5020, Salzburg, Austria.
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Beim JA, Oxenham AJ, Wojtczak M. No effects of attention or visual perceptual load on cochlear function, as measured with stimulus-frequency otoacoustic emissions. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 146:1475. [PMID: 31472524 PMCID: PMC6715442 DOI: 10.1121/1.5123391] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 08/02/2019] [Accepted: 08/05/2019] [Indexed: 06/10/2023]
Abstract
The effects of selectively attending to a target stimulus in a background containing distractors can be observed in cortical representations of sound as an attenuation of the representation of distractor stimuli. The locus in the auditory system at which attentional modulations first arise is unknown, but anatomical evidence suggests that cortically driven modulation of neural activity could extend as peripherally as the cochlea itself. Previous studies of selective attention have used otoacoustic emissions to probe cochlear function under varying conditions of attention with mixed results. In the current study, two experiments combined visual and auditory tasks to maximize sustained attention, perceptual load, and cochlear dynamic range in an attempt to improve the likelihood of observing selective attention effects on cochlear responses. Across a total of 45 listeners in the two experiments, no systematic effects of attention or perceptual load were observed on stimulus-frequency otoacoustic emissions. The results revealed significant between-subject variability in the otoacoustic-emission measure of cochlear function that does not depend on listener performance in the behavioral tasks and is not related to movement-generated noise. The findings suggest that attentional modulation of auditory information in humans arises at stages of processing beyond the cochlea.
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Affiliation(s)
- Jordan A Beim
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, Minnesota 55455, USA
| | - Andrew J Oxenham
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, Minnesota 55455, USA
| | - Magdalena Wojtczak
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, Minnesota 55455, USA
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Alho K, Żarnowiec K, Gorina-Careta N, Escera C. Phonological Task Enhances the Frequency-Following Response to Deviant Task-Irrelevant Speech Sounds. Front Hum Neurosci 2019; 13:245. [PMID: 31379540 PMCID: PMC6646721 DOI: 10.3389/fnhum.2019.00245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 07/01/2019] [Indexed: 11/13/2022] Open
Abstract
In electroencephalography (EEG) measurements, processing of periodic sounds in the ascending auditory pathway generates the frequency-following response (FFR) phase-locked to the fundamental frequency (F0) and its harmonics of a sound. We measured FFRs to the steady-state (vowel) part of syllables /ba/ and /aw/ occurring in binaural rapid streams of speech sounds as frequently repeating standard syllables or as infrequent (p = 0.2) deviant syllables among standard /wa/ syllables. Our aim was to study whether concurrent active phonological processing affects early processing of irrelevant speech sounds reflected by FFRs to these sounds. To this end, during syllable delivery, our healthy adult participants performed tasks involving written letters delivered on a computer screen in a rapid stream. The stream consisted of vowel letters written in red, infrequently occurring consonant letters written in the same color, and infrequently occurring vowel letters written in blue. In the phonological task, the participants were instructed to press a response key to the consonant letters differing phonologically but not in color from the frequently occurring red vowels, whereas in the non-phonological task, they were instructed to respond to the vowel letters written in blue differing only in color from the frequently occurring red vowels. We observed that the phonological task enhanced responses to deviant /ba/ syllables but not responses to deviant /aw/ syllables. This suggests that active phonological task performance may enhance processing of such small changes in irrelevant speech sounds as the 30-ms difference in the initial formant-transition time between the otherwise identical syllables /ba/ and /wa/ used in the present study.
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Affiliation(s)
- Kimmo Alho
- Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland.,Institute of Biomedicine, Paris Descartes University, Paris, France
| | - Katarzyna Żarnowiec
- Brainlab-Cognitive Neuroscience Research Group, Department of Clinical Psychology and Psychobiology, Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Natàlia Gorina-Careta
- Brainlab-Cognitive Neuroscience Research Group, Department of Clinical Psychology and Psychobiology, Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Barcelona, Spain
| | - Carles Escera
- Brainlab-Cognitive Neuroscience Research Group, Department of Clinical Psychology and Psychobiology, Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain.,Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Barcelona, Spain
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35
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Zhang X, Gong Q. Frequency-Following Responses to Complex Tones at Different Frequencies Reflect Different Source Configurations. Front Neurosci 2019; 13:130. [PMID: 30872990 PMCID: PMC6402474 DOI: 10.3389/fnins.2019.00130] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 02/05/2019] [Indexed: 11/13/2022] Open
Abstract
The neural generators of the frequency-following response (FFR), a neural response widely used to study the human auditory system, remain unclear. There is evidence that the balance between cortical and subcortical contributions to the FFR varies with stimulus frequency. In this study, we tried to clarify whether this variation extended to subcortical nuclei at higher stimulus frequencies where cortical sources were inactive. We evoked FFRs, in 17 human listeners with normal hearing (9 female), with three complex tones with missing-fundamentals corresponding to musical tones C4 (262 Hz), E4 (330 Hz), and G4 (393 Hz) presented to left, right, or both ears. Source imaging results confirmed the dominance of subcortical activity underlying both fundamental frequency (F0) and second harmonic (H2) components of the FFR. Importantly, several FFR features (spatial complexity, scalp distributions of spectral strength and inter-trial phase coherence, and functional connectivity patterns) varied systematically with stimulus F0, suggesting an unfixed source configuration. We speculated that the variation of FFR source configuration with stimulus frequency resulted from changing relative contributions of subcortical nuclei. Supportively, topographic comparison between the FFR and the auditory brainstem response (ABR) evoked by clicks revealed that the topography of the F0 component resembled that of the click-ABR at an earlier latency when stimulus F0 was higher and that the topography of the H2 component resembled that of the click-ABR at a nearly fixed latency regardless of stimulus F0, particularly for binaurally evoked FFRs. Possible generation sites of the FFR and implications for future studies were discussed.
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Affiliation(s)
- Xiaochen Zhang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Qin Gong
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China.,Research Center of Biomedical Engineering, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China
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36
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Ruggles DR, Tausend AN, Shamma SA, Oxenham AJ. Cortical markers of auditory stream segregation revealed for streaming based on tonotopy but not pitch. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2018; 144:2424. [PMID: 30404514 PMCID: PMC6909992 DOI: 10.1121/1.5065392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 10/05/2018] [Accepted: 10/08/2018] [Indexed: 06/08/2023]
Abstract
The brain decomposes mixtures of sounds, such as competing talkers, into perceptual streams that can be attended to individually. Attention can enhance the cortical representation of streams, but it is unknown what acoustic features the enhancement reflects, or where in the auditory pathways attentional enhancement is first observed. Here, behavioral measures of streaming were combined with simultaneous low- and high-frequency envelope-following responses (EFR) that are thought to originate primarily from cortical and subcortical regions, respectively. Repeating triplets of harmonic complex tones were presented with alternating fundamental frequencies. The tones were filtered to contain either low-numbered spectrally resolved harmonics, or only high-numbered unresolved harmonics. The behavioral results confirmed that segregation can be based on either tonotopic or pitch cues. The EFR results revealed no effects of streaming or attention on subcortical responses. Cortical responses revealed attentional enhancement under conditions of streaming, but only when tonotopic cues were available, not when streaming was based only on pitch cues. The results suggest that the attentional modulation of phase-locked responses is dominated by tonotopically tuned cortical neurons that are insensitive to pitch or periodicity cues.
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Affiliation(s)
- Dorea R Ruggles
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, Minnesota 55455, USA
| | - Alexis N Tausend
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, Minnesota 55455, USA
| | - Shihab A Shamma
- Electrical and Computer Engineering Department & Institute for Systems, University of Maryland, College Park, Maryland 20740, USA
| | - Andrew J Oxenham
- Department of Psychology, University of Minnesota, 75 East River Parkway, Minneapolis, Minnesota 55455, USA
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37
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Anderson S, Ellis R, Mehta J, Goupell MJ. Age-related differences in binaural masking level differences: behavioral and electrophysiological evidence. J Neurophysiol 2018; 120:2939-2952. [PMID: 30230989 DOI: 10.1152/jn.00255.2018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The effects of aging and stimulus configuration on binaural masking level differences (BMLDs) were measured behaviorally and electrophysiologically, using the frequency-following response (FFR) to target brainstem/midbrain encoding. The tests were performed in 15 younger normal-hearing (<30 yr) and 15 older normal-hearing (>60 yr) participants. The stimuli consisted of a 500-Hz target tone embedded in a narrowband (50-Hz bandwidth) or wideband (1,500-Hz bandwidth) noise masker. The interaural phase conditions included NoSo (tone and noise presented interaurally in-phase), NoSπ (noise presented interaurally in-phase and tone presented out-of-phase), and NπSo (noise presented interaurally out-of-phase and tone presented in-phase) configurations. In the behavioral experiment, aging reduced the magnitude of the BMLD. The magnitude of the BMLD was smaller for the NoSo-NπSo threshold difference compared with the NoSo-NoSπ threshold difference, and it was also smaller in narrowband compared with wideband conditions, consistent with previous measurements. In the electrophysiology experiment, older participants had reduced FFR magnitudes and smaller differences between configurations. There were significant changes in FFR magnitude between the NoSo to NoSπ configurations but not between the NoSo to NπSo configurations. The age-related reduction in FFR magnitudes suggests a temporal processing deficit, but no correlation was found between FFR magnitudes and behavioral BMLDs. Therefore, independent mechanisms may be contributing to the behavioral and neural deficits. Specifically, older participants had higher behavioral thresholds than younger participants for the NoSπ and NπSo configurations but had equivalent thresholds for the NoSo configuration. However, FFR magnitudes were reduced in older participants across all configurations. NEW & NOTEWORTHY Behavioral and electrophysiological testing reveal an aging effect for stimuli presented in wideband and narrowband noise conditions, such that behavioral binaural masking level differences and subcortical spectral magnitudes are reduced in older compared with younger participants. These deficits in binaural processing may limit the older participant's ability to use spatial cues to understand speech in environments containing competing sound sources.
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Affiliation(s)
- Samira Anderson
- Department of Hearing and Speech Sciences, University of Maryland College Park, Maryland
| | - Robert Ellis
- Department of Hearing and Speech Sciences, University of Maryland College Park, Maryland
| | - Julie Mehta
- Department of Hearing and Speech Sciences, University of Maryland College Park, Maryland
| | - Matthew J Goupell
- Department of Hearing and Speech Sciences, University of Maryland College Park, Maryland
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38
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Neural Signatures of the Processing of Temporal Patterns in Sound. J Neurosci 2018; 38:5466-5477. [PMID: 29773757 DOI: 10.1523/jneurosci.0346-18.2018] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 04/13/2018] [Accepted: 05/06/2018] [Indexed: 11/21/2022] Open
Abstract
The ability to detect regularities in sound (i.e., recurring structure) is critical for effective perception, enabling, for example, change detection and prediction. Two seemingly unconnected lines of research concern the neural operations involved in processing regularities: one investigates how neural activity synchronizes with temporal regularities (e.g., frequency modulation; FM) in sounds, whereas the other focuses on increases in sustained activity during stimulation with repeating tone-frequency patterns. In three electroencephalography studies with male and female human participants, we investigated whether neural synchronization and sustained neural activity are dissociable, or whether they are functionally interdependent. Experiment I demonstrated that neural activity synchronizes with temporal regularity (FM) in sounds, and that sustained activity increases concomitantly. In Experiment II, phase coherence of FM in sounds was parametrically varied. Although neural synchronization was more sensitive to changes in FM coherence, such changes led to a systematic modulation of both neural synchronization and sustained activity, with magnitude increasing as coherence increased. In Experiment III, participants either performed a duration categorization task on the sounds, or a visual object tracking task to distract attention. Neural synchronization was observed regardless of task, whereas the sustained response was observed only when attention was on the auditory task, not under (visual) distraction. The results suggest that neural synchronization and sustained activity levels are functionally linked: both are sensitive to regularities in sounds. However, neural synchronization might reflect a more sensory-driven response to regularity, compared with sustained activity which may be influenced by attentional, contextual, or other experiential factors.SIGNIFICANCE STATEMENT Optimal perception requires that the auditory system detects regularities in sounds. Synchronized neural activity and increases in sustained neural activity both appear to index the detection of a regularity, but the functional interrelation of these two neural signatures is unknown. In three electroencephalography experiments, we measured both signatures concomitantly while listeners were presented with sounds containing frequency modulations that differed in their regularity. We observed that both neural signatures are sensitive to temporal regularity in sounds, although they functionally decouple when a listener is distracted by a demanding visual task. Our data suggest that neural synchronization reflects a more automatic response to regularity compared with sustained activity, which may be influenced by attentional, contextual, or other experiential factors.
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