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Research paper thumbnail of Subcortical Neural Synchrony and Absolute Thresholds Predict Frequency Discrimination Independently

Journal of the Association for Research in Otolaryngology, 2013

The neural mechanisms of pitch coding have been debated for more than a century. The two main mec... more The neural mechanisms of pitch coding have been debated for more than a century. The two main mechanisms are coding based on the profiles of neural firing rates across auditory nerve fibers with different characteristic frequencies (place-rate coding), and coding based on the phase-locked temporal pattern of neural firing (temporal coding). Phase locking precision can be partly assessed by recording the frequency-following response (FFR), a scalp-recorded electrophysiological response that reflects synchronous activity in subcortical neurons. Although features of the FFR have been widely used as indices of pitch coding acuity, only a handful of studies have directly investigated the relation between the FFR and behavioral pitch judgments. Furthermore, the contribution of degraded neural synchrony (as indexed by the FFR) to the pitch perception impairments of older listeners and those with hearing loss is not well known. Here, the relation between the FFR and pure-tone frequency disc...

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Research paper thumbnail of Effects of age on electrophysiological measures of cochlear synaptopathy in humans

Hearing Research, 2020

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Research paper thumbnail of Effects of age on psychophysical measures of auditory temporal processing and speech reception at low and high levels

Hearing Research, 2021

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Research paper thumbnail of The upper frequency limit for the use of phase locking to code temporal fine structure in humans: A compilation of viewpoints

Hearing Research, 2019

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Research paper thumbnail of Sub-clinical auditory neural deficits in patients with type 1 Diabetes Mellitus

The Journal of the Acoustical Society of America, 2016

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Research paper thumbnail of The effect of tone-vocoding on spatial release from masking for old, hearing-impaired listeners

The Journal of the Acoustical Society of America, 2017

Old, hearing-impaired listeners generally benefit little from lateral separation of multiple talk... more Old, hearing-impaired listeners generally benefit little from lateral separation of multiple talkers when listening to one of them. This study aimed to determine how spatial release from masking (SRM) in such listeners is affected when the interaural time differences (ITDs) in the temporal fine structure (TFS) are manipulated by tone-vocoding (TVC) at the ears by a master hearing aid system. Word recall was compared, with and without TVC, when target and masker sentences from a closed set were played simultaneously from the front loudspeaker (co-located) and when the maskers were played 45° to the left and right of the listener (separated). For 20 hearing-impaired listeners aged 64 to 86, SRM was 3.7 dB smaller with TVC than without TVC. This difference in SRM correlated with mean audiometric thresholds below 1.5 kHz, even when monaural TFS sensitivity (discrimination of frequency-shifts in identically filtered complexes) was partialed out, suggesting that low-frequency audiometric ...

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Research paper thumbnail of Effects of noise exposure on young adults with normal audiograms I: Electrophysiology

Hearing research, Jan 2, 2016

Noise-induced cochlear synaptopathy has been demonstrated in numerous rodent studies. In these an... more Noise-induced cochlear synaptopathy has been demonstrated in numerous rodent studies. In these animal models, the disorder is characterized by a reduction in amplitude of wave I of the auditory brainstem response (ABR) to high-level stimuli, whereas the response at threshold is unaffected. The aim of the present study was to determine if this disorder is prevalent in young adult humans with normal audiometric hearing. One hundred and twenty six participants (75 females) aged 18-36 were tested. Participants had a wide range of lifetime noise exposures as estimated by a structured interview. Audiometric thresholds did not differ across noise exposures up to 8 kHz, although 16-kHz audiometric thresholds were elevated with increasing noise exposure for females but not for males. ABRs were measured in response to high-pass (1.5 kHz) filtered clicks of 80 and 100 dB peSPL. Frequency-following responses (FFRs) were measured to 80 dB SPL pure tones from 240 to 285 Hz, and to 80 dB SPL 4 kHz...

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Research paper thumbnail of Toward a Diagnostic Test for Hidden Hearing Loss

Trends in Hearing, 2016

Cochlear synaptopathy (or hidden hearing loss), due to noise exposure or aging, has been demonstr... more Cochlear synaptopathy (or hidden hearing loss), due to noise exposure or aging, has been demonstrated in animal models using histological techniques. However, diagnosis of the condition in individual humans is problematic because of (a) test reliability and (b) lack of a gold standard validation measure. Wave I of the transient-evoked auditory brainstem response is a noninvasive electrophysiological measure of auditory nerve function and has been validated in the animal models. However, in humans, Wave I amplitude shows high variability both between and within individuals. The frequency-following response, a sustained evoked potential reflecting synchronous neural activity in the rostral brainstem, is potentially more robust than auditory brainstem response Wave I. However, the frequency-following response is a measure of central activity and may be dependent on individual differences in central processing. Psychophysical measures are also affected by intersubject variability in cen...

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Research paper thumbnail of Specificity of the Human Frequency Following Response for Carrier and Modulation Frequency Assessed Using Adaptation

Journal of the Association for Research in Otolaryngology, 2015

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Research paper thumbnail of Losing the music: aging affects the perception and subcortical neural representation of musical harmony

The Journal of neuroscience : the official journal of the Society for Neuroscience, Jan 4, 2015

When two musical notes with simple frequency ratios are played simultaneously, the resulting musi... more When two musical notes with simple frequency ratios are played simultaneously, the resulting musical chord is pleasing and evokes a sense of resolution or "consonance". Complex frequency ratios, on the other hand, evoke feelings of tension or "dissonance". Consonance and dissonance form the basis of harmony, a central component of Western music. In earlier work, we provided evidence that consonance perception is based on neural temporal coding in the brainstem (Bones et al., 2014). Here, we show that for listeners with clinically normal hearing, aging is associated with a decline in both the perceptual distinction and the distinctiveness of the neural representations of different categories of two-note chords. Compared with younger listeners, older listeners rated consonant chords as less pleasant and dissonant chords as more pleasant. Older listeners also had less distinct neural representations of consonant and dissonant chords as measured using a Neural Conson...

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Research paper thumbnail of Subcortical representation of musical dyads: Individual differences and neural generators

Hearing Research, 2015

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Research paper thumbnail of Central Auditory Masking by an Illusory Tone

PLoS ONE, 2013

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Research paper thumbnail of The human ???pitch center??? responds differently to iterated noise and Huggins pitch

NeuroReport, 2007

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Research paper thumbnail of Phase locked neural activity in the human brainstem predicts preference for musical consonance

Neuropsychologia, 2014

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Research paper thumbnail of The effect of stimulus context on pitch representations in the human auditory cortex

NeuroImage, 2010

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Research paper thumbnail of Perceived continuity and pitch shifts for complex tones with unresolved harmonics

The Journal of the Acoustical Society of America, 2010

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Research paper thumbnail of Pitch discrimination interference between binaural and monaural or diotic pitches

The Journal of the Acoustical Society of America, 2009

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Research paper thumbnail of Further examination of pitch discrimination interference between complex tones containing resolved harmonics

The Journal of the Acoustical Society of America, 2009

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Research paper thumbnail of Suppression and the upward spread of masking

The Journal of the Acoustical Society of America, 1998

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Research paper thumbnail of Pitch matches between unresolved complex tones differing by a single interpulse interval

The Journal of the Acoustical Society of America, 2000

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Research paper thumbnail of Subcortical Neural Synchrony and Absolute Thresholds Predict Frequency Discrimination Independently

Journal of the Association for Research in Otolaryngology, 2013

The neural mechanisms of pitch coding have been debated for more than a century. The two main mec... more The neural mechanisms of pitch coding have been debated for more than a century. The two main mechanisms are coding based on the profiles of neural firing rates across auditory nerve fibers with different characteristic frequencies (place-rate coding), and coding based on the phase-locked temporal pattern of neural firing (temporal coding). Phase locking precision can be partly assessed by recording the frequency-following response (FFR), a scalp-recorded electrophysiological response that reflects synchronous activity in subcortical neurons. Although features of the FFR have been widely used as indices of pitch coding acuity, only a handful of studies have directly investigated the relation between the FFR and behavioral pitch judgments. Furthermore, the contribution of degraded neural synchrony (as indexed by the FFR) to the pitch perception impairments of older listeners and those with hearing loss is not well known. Here, the relation between the FFR and pure-tone frequency disc...

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Research paper thumbnail of Effects of age on electrophysiological measures of cochlear synaptopathy in humans

Hearing Research, 2020

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Effects of age on psychophysical measures of auditory temporal processing and speech reception at low and high levels

Hearing Research, 2021

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The upper frequency limit for the use of phase locking to code temporal fine structure in humans: A compilation of viewpoints

Hearing Research, 2019

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Sub-clinical auditory neural deficits in patients with type 1 Diabetes Mellitus

The Journal of the Acoustical Society of America, 2016

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The effect of tone-vocoding on spatial release from masking for old, hearing-impaired listeners

The Journal of the Acoustical Society of America, 2017

Old, hearing-impaired listeners generally benefit little from lateral separation of multiple talk... more Old, hearing-impaired listeners generally benefit little from lateral separation of multiple talkers when listening to one of them. This study aimed to determine how spatial release from masking (SRM) in such listeners is affected when the interaural time differences (ITDs) in the temporal fine structure (TFS) are manipulated by tone-vocoding (TVC) at the ears by a master hearing aid system. Word recall was compared, with and without TVC, when target and masker sentences from a closed set were played simultaneously from the front loudspeaker (co-located) and when the maskers were played 45° to the left and right of the listener (separated). For 20 hearing-impaired listeners aged 64 to 86, SRM was 3.7 dB smaller with TVC than without TVC. This difference in SRM correlated with mean audiometric thresholds below 1.5 kHz, even when monaural TFS sensitivity (discrimination of frequency-shifts in identically filtered complexes) was partialed out, suggesting that low-frequency audiometric ...

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Research paper thumbnail of Effects of noise exposure on young adults with normal audiograms I: Electrophysiology

Hearing research, Jan 2, 2016

Noise-induced cochlear synaptopathy has been demonstrated in numerous rodent studies. In these an... more Noise-induced cochlear synaptopathy has been demonstrated in numerous rodent studies. In these animal models, the disorder is characterized by a reduction in amplitude of wave I of the auditory brainstem response (ABR) to high-level stimuli, whereas the response at threshold is unaffected. The aim of the present study was to determine if this disorder is prevalent in young adult humans with normal audiometric hearing. One hundred and twenty six participants (75 females) aged 18-36 were tested. Participants had a wide range of lifetime noise exposures as estimated by a structured interview. Audiometric thresholds did not differ across noise exposures up to 8 kHz, although 16-kHz audiometric thresholds were elevated with increasing noise exposure for females but not for males. ABRs were measured in response to high-pass (1.5 kHz) filtered clicks of 80 and 100 dB peSPL. Frequency-following responses (FFRs) were measured to 80 dB SPL pure tones from 240 to 285 Hz, and to 80 dB SPL 4 kHz...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Toward a Diagnostic Test for Hidden Hearing Loss

Trends in Hearing, 2016

Cochlear synaptopathy (or hidden hearing loss), due to noise exposure or aging, has been demonstr... more Cochlear synaptopathy (or hidden hearing loss), due to noise exposure or aging, has been demonstrated in animal models using histological techniques. However, diagnosis of the condition in individual humans is problematic because of (a) test reliability and (b) lack of a gold standard validation measure. Wave I of the transient-evoked auditory brainstem response is a noninvasive electrophysiological measure of auditory nerve function and has been validated in the animal models. However, in humans, Wave I amplitude shows high variability both between and within individuals. The frequency-following response, a sustained evoked potential reflecting synchronous neural activity in the rostral brainstem, is potentially more robust than auditory brainstem response Wave I. However, the frequency-following response is a measure of central activity and may be dependent on individual differences in central processing. Psychophysical measures are also affected by intersubject variability in cen...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Specificity of the Human Frequency Following Response for Carrier and Modulation Frequency Assessed Using Adaptation

Journal of the Association for Research in Otolaryngology, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Losing the music: aging affects the perception and subcortical neural representation of musical harmony

The Journal of neuroscience : the official journal of the Society for Neuroscience, Jan 4, 2015

When two musical notes with simple frequency ratios are played simultaneously, the resulting musi... more When two musical notes with simple frequency ratios are played simultaneously, the resulting musical chord is pleasing and evokes a sense of resolution or "consonance". Complex frequency ratios, on the other hand, evoke feelings of tension or "dissonance". Consonance and dissonance form the basis of harmony, a central component of Western music. In earlier work, we provided evidence that consonance perception is based on neural temporal coding in the brainstem (Bones et al., 2014). Here, we show that for listeners with clinically normal hearing, aging is associated with a decline in both the perceptual distinction and the distinctiveness of the neural representations of different categories of two-note chords. Compared with younger listeners, older listeners rated consonant chords as less pleasant and dissonant chords as more pleasant. Older listeners also had less distinct neural representations of consonant and dissonant chords as measured using a Neural Conson...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Subcortical representation of musical dyads: Individual differences and neural generators

Hearing Research, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Central Auditory Masking by an Illusory Tone

PLoS ONE, 2013

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The human ???pitch center??? responds differently to iterated noise and Huggins pitch

NeuroReport, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Phase locked neural activity in the human brainstem predicts preference for musical consonance

Neuropsychologia, 2014

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The effect of stimulus context on pitch representations in the human auditory cortex

NeuroImage, 2010

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Perceived continuity and pitch shifts for complex tones with unresolved harmonics

The Journal of the Acoustical Society of America, 2010

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Pitch discrimination interference between binaural and monaural or diotic pitches

The Journal of the Acoustical Society of America, 2009

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Further examination of pitch discrimination interference between complex tones containing resolved harmonics

The Journal of the Acoustical Society of America, 2009

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Suppression and the upward spread of masking

The Journal of the Acoustical Society of America, 1998

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Pitch matches between unresolved complex tones differing by a single interpulse interval

The Journal of the Acoustical Society of America, 2000

Bookmarks Related papers MentionsView impact