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  1. Book ; Online ; E-Book: Auditory Brainstem Evoked Potentials

    Krishnan, Ananthanarayan

    Clinical and Research Applications

    2020  

    Abstract: Auditory Brainstem Evoked Potentials: Clinical and Research Applications provides a solid foundation of the theoretical principles of auditory evoked potentials. This understanding is important for both the development of optimal clinical test strategies, ...

    Title variant Auditory Brainstem Evoked Potentials
    Abstract Auditory Brainstem Evoked Potentials: Clinical and Research Applications provides a solid foundation of the theoretical principles of auditory evoked potentials. This understanding is important for both the development of optimal clinical test strategies, and interpretation of test results. Developed for graduate-level audiology students, this comprehensive text aims to build a fundamental understanding of auditory evoked brainstem responses (ABR), and their relationship to normal and impaired auditory function, as well as its various audiologic and neurootologic applications.
    MeSH term(s) Evoked Potentials, Auditory, Brain Stem/physiology ; Audiometry, Evoked Response ; Auditory Diseases, Central/diagnosis
    Subject code 616.8047547
    Language English
    Size 1 online resource (401 pages)
    Publisher Plural Publishing, Incorporated
    Publishing place San Diego
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    ISBN 1-63550-252-7 ; 1-63550-239-X ; 978-1-63550-252-7 ; 978-1-63550-239-8
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  2. Article ; Online: Frequency-Following Response to Steady-State Vowel in Quiet and Background Noise Among Marching Band Participants With Normal Hearing.

    Suresh, Chandan H / Krishnan, Ananthanarayan

    American journal of audiology

    2022  Volume 31, Issue 3, Page(s) 719–736

    Abstract: Objective: Human studies enrolling individuals at high risk for cochlear synaptopathy (CS) have reported difficulties in speech perception in adverse listening conditions. The aim of this study is to determine if these individuals show a degradation in ... ...

    Abstract Objective: Human studies enrolling individuals at high risk for cochlear synaptopathy (CS) have reported difficulties in speech perception in adverse listening conditions. The aim of this study is to determine if these individuals show a degradation in the neural encoding of speech in quiet and in the presence of background noise as reflected in neural phase-locking to both envelope periodicity and temporal fine structure (TFS). To our knowledge, there are no published reports that have specifically examined the neural encoding of both envelope periodicity and TFS of speech stimuli (in quiet and in adverse listening conditions) among a sample with loud-sound exposure history who are at risk for CS.
    Method: Using scalp-recorded frequency-following response (FFR), the authors evaluated the neural encoding of envelope periodicity (FFR
    Results: The results showed no group differences in the neural encoding of either the FFR
    Conclusions: These results appear to be in line with a music experience-dependent enhancement of F2 harmonics. However, due to sound overexposure in the high-risk group, the role of homeostatic central compensation cannot be ruled out. A larger scale data set with different noise exposure background, longitudinal measurements with an array of behavioral and electrophysiological tests is needed to disentangle the nature of the complex interaction between the effects of central compensatory gain and experience-dependent enhancement.
    MeSH term(s) Acoustic Stimulation/methods ; Auditory Perception/physiology ; Hearing ; Humans ; Noise ; Sound ; Speech Perception/physiology
    Language English
    Publishing date 2022-08-09
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1162315-9
    ISSN 1558-9137 ; 1059-0889
    ISSN (online) 1558-9137
    ISSN 1059-0889
    DOI 10.1044/2022_AJA-21-00226
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Search for Electrophysiological Indices of Hidden Hearing Loss in Humans: Click Auditory Brainstem Response Across Sound Levels and in Background Noise.

    Suresh, Chandan H / Krishnan, Ananthanarayan

    Ear and hearing

    2020  Volume 42, Issue 1, Page(s) 53–67

    Abstract: Objectives: Recent studies in animals indicate that even moderate levels of exposure to noise can damage synaptic ribbons between the inner hair cells and auditory nerve fibers without affecting audiometric thresholds, giving rise to the use of the term ...

    Abstract Objectives: Recent studies in animals indicate that even moderate levels of exposure to noise can damage synaptic ribbons between the inner hair cells and auditory nerve fibers without affecting audiometric thresholds, giving rise to the use of the term "hidden hearing loss" (HHL). Despite evidence across several animal species, there is little consistent evidence for HHL in humans. The aim of the study is to evaluate potential electrophysiological changes specific to individuals at risk for HHL.
    Design: Participants forming the high-risk experimental group consisted of 28 young normal-hearing adults who participated in marching band for at least 5 years. Twenty-eight age-matched normal-hearing adults who were not part of the marching band and had little or no history of recreational or occupational exposure to loud sounds formed the low-risk control group. Measurements included pure tone audiometry of conventional and high frequencies, distortion product otoacoustic emissions, and electrophysiological measures of auditory nerve and brainstem function as reflected in the click-evoked auditory brainstem response (ABR). In experiment 1, ABRs were recorded in a quiet background across stimulus levels (30-90 dB nHL) presented in 10 dB steps. In experiment 2, the ABR was elicited by a 70 dB nHL click stimulus presented in a quiet background, and in the presence of simultaneous ipsilateral continuous broadband noise presented at 50, 60, and 70 dB SPL using an insert earphone (Etymotic, ER2).
    Results: There were no differences between the low- and high-risk groups in audiometric thresholds or distortion product otoacoustic emission amplitude. Experiment 1 demonstrated smaller wave-I amplitudes at moderate and high sound levels for high-risk compared to low-risk group with similar wave III and wave V amplitude. Enhanced amplitude ratio V/I, particularly at moderate sound level (60 dB nHL), suggesting central compensation for reduced input from the periphery for high-risk group. The results of experiment 2 show that the decrease in wave I amplitude with increasing background noise level was relatively smaller for the high-risk compared to the low-risk group. However, wave V amplitude reduction was essentially similar for both groups. These results suggest that masking induced wave I amplitude reduction is smaller in individuals at high risk for cochlear synaptopathy. Unlike previous studies, we did not observe a difference in the noise-induced wave V latency shift between low- and high-risk groups.
    Conclusions: Results of experiment 1 are consistent with findings in both animal studies (that suggest cochlear synaptopathy involving selective damage of low-spontaneous rate and medium-spontaneous rate fibers), and in several human studies that show changes in a range of ABR metrics that suggest the presence of cochlear synaptopathy. However, without postmortem examination by harvesting human temporal bone (the gold standard for identifying synaptopathy) with different noise exposure background, no direct inferences can be derived for the presence/extent of cochlear synaptopathy in high-risk group with high sound over-exposure history. Results of experiment 2 demonstrate that to the extent response amplitude reflects both the number of neural elements responding and the neural synchrony of the responding elements, the relatively smaller change in response amplitude for the high-risk group would suggest a reduced susceptibility to masking. One plausible mechanism would be that suppressive effects that kick in at moderate to high levels are different in these two groups, particularly at moderate levels of the masking noise. Altogether, a larger scale dataset with different noise exposure background, longitudinal measurements (changes due to recreational over-exposure by studying middle-school to high-school students enrolled in marching band) with an array of behavioral and electrophysiological tests are needed to understand the complex pathogenesis of sound over-exposure damage in normal-hearing individuals.
    MeSH term(s) Adult ; Animals ; Audiometry, Pure-Tone ; Auditory Threshold ; Cochlea ; Evoked Potentials, Auditory, Brain Stem ; Hearing Loss, Noise-Induced/diagnosis ; Humans ; Noise
    Language English
    Publishing date 2020-07-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 603093-2
    ISSN 1538-4667 ; 0196-0202
    ISSN (online) 1538-4667
    ISSN 0196-0202
    DOI 10.1097/AUD.0000000000000905
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Cortical hemisphere preference and brainstem ear asymmetry reflect experience-dependent functional modulation of pitch.

    Krishnan, Ananthanarayan / Suresh, Chandan H / Gandour, Jackson T

    Brain and language

    2021  Volume 221, Page(s) 104995

    Abstract: Temporal attributes of pitch processing at cortical and subcortical levels are differentially weighted and well-coordinated. The question is whether language experience induces functional modulation of hemispheric preference complemented by brainstem ear ...

    Abstract Temporal attributes of pitch processing at cortical and subcortical levels are differentially weighted and well-coordinated. The question is whether language experience induces functional modulation of hemispheric preference complemented by brainstem ear symmetry for pitch processing. Brainstem frequency-following and cortical pitch responses were recorded concurrently from Mandarin and English participants. A Mandarin syllable with a rising pitch contour was presented to both ears with monaural stimulation. At the cortical level, left ear stimulation in the Chinese group revealed an experience-dependent response for pitch processing in the right hemisphere, consistent with a functionalaccount. The English group revealed a contralateral hemisphere preference consistent with a structuralaccount. At the brainstem level, Chinese participants showed a functional leftward ear asymmetry, whereas English were consistent with a structural account. Overall, language experience modulates both cortical hemispheric preference and brainstem ear asymmetry in a complementary manner to optimize processing of temporal attributes of pitch.
    MeSH term(s) Acoustic Stimulation ; Brain Stem ; Electroencephalography ; Evoked Potentials, Auditory, Brain Stem ; Humans ; Pitch Perception
    Language English
    Publishing date 2021-07-22
    Publishing country Netherlands
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 7448-2
    ISSN 1090-2155 ; 0093-934X
    ISSN (online) 1090-2155
    ISSN 0093-934X
    DOI 10.1016/j.bandl.2021.104995
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Human frequency following responses to iterated rippled noise with positive and negative gain: Differential sensitivity to waveform envelope and temporal fine-structure.

    Ananthakrishnan, Saradha / Krishnan, Ananthanarayan

    Hearing research

    2018  Volume 367, Page(s) 113–123

    Abstract: The perceived pitch of iterated rippled noise (IRN) with negative gain (IRNn) is an octave lower than that of IRN with positive gain (IRNp). IRNp and IRNn have identical waveform envelopes (ENV), but differing stimulus waveform fine structure (TFS), ... ...

    Abstract The perceived pitch of iterated rippled noise (IRN) with negative gain (IRNn) is an octave lower than that of IRN with positive gain (IRNp). IRNp and IRNn have identical waveform envelopes (ENV), but differing stimulus waveform fine structure (TFS), which likely accounts for this perceived pitch difference. Here, we examine whether differences in the temporal pattern of phase-locked activity reflected in the human brainstem Frequency Following Response (FFR) elicited by IRNp and IRNn can account for the differences in perceived pitch for the two stimuli. FFRs using a single onset polarity were measured in 13 normal-hearing, adult listeners in response to IRNp and IRNn stimuli with 2 ms, and 4 ms delay. Autocorrelation functions (ACFs) and Fast Fourier Transforms (FFTs) were used to evaluate the dominant periodicity and spectral pattern (harmonic spacing) in the phase-locked FFR neural activity. For both delays, the harmonic spacing in the spectra corresponded more strongly with the perceived lowering of pitch from IRNp to IRNn, compared to the ACFs. These results suggest that the FFR elicited by a single polarity stimulus reflects phase-locking to both stimulus ENV and TFS. A post-hoc experiment evaluating the FFR phase-locked activity to ENV (FFR
    MeSH term(s) Acoustic Stimulation/methods ; Acoustics ; Adult ; Brain Stem/physiology ; Cues ; Female ; Humans ; Male ; Noise/adverse effects ; Perceptual Masking ; Pitch Discrimination ; Pitch Perception ; Sound Spectrography ; Time Factors ; Young Adult
    Language English
    Publishing date 2018-07-29
    Publishing country Netherlands
    Document type Comparative Study ; Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 282629-x
    ISSN 1878-5891 ; 0378-5955
    ISSN (online) 1878-5891
    ISSN 0378-5955
    DOI 10.1016/j.heares.2018.07.009
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Tone language experience-dependent advantage in pitch representation in brainstem and auditory cortex is maintained under reverberation.

    Krishnan, Ananthanarayan / Suresh, Chandan H / Gandour, Jackson T

    Hearing research

    2019  Volume 377, Page(s) 61–71

    Abstract: Long-term language and music experience enhances neural representation of temporal attributes of pitch in the brainstem and auditory cortex in favorable listening conditions. Herein we examine whether brainstem and cortical pitch mechanisms-shaped by ... ...

    Abstract Long-term language and music experience enhances neural representation of temporal attributes of pitch in the brainstem and auditory cortex in favorable listening conditions. Herein we examine whether brainstem and cortical pitch mechanisms-shaped by long-term language experience-maintain this advantage in the presence of reverberation-induced degradation in pitch representation. Brainstem frequency following responses (FFR) and cortical pitch responses (CPR) were recorded concurrently from Chinese and English-speaking natives, using a Mandarin word exhibiting a high rising pitch (/yi
    MeSH term(s) Acoustic Stimulation ; Adult ; Auditory Cortex/physiology ; Brain Stem/physiology ; Evoked Potentials, Auditory ; Evoked Potentials, Auditory, Brain Stem ; Female ; Humans ; Male ; Noise/adverse effects ; Perceptual Masking ; Periodicity ; Pitch Discrimination ; Speech Acoustics ; Speech Perception ; Time Factors ; Vibration ; Young Adult
    Language English
    Publishing date 2019-03-15
    Publishing country Netherlands
    Document type Comparative Study ; Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 282629-x
    ISSN 1878-5891 ; 0378-5955
    ISSN (online) 1878-5891
    ISSN 0378-5955
    DOI 10.1016/j.heares.2019.03.009
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Human Frequency Following Responses to Vocoded Speech: Amplitude Modulation Versus Amplitude Plus Frequency Modulation.

    Suresh, Chandan H / Krishnan, Ananthanarayan / Luo, Xin

    Ear and hearing

    2019  Volume 41, Issue 2, Page(s) 300–311

    Abstract: Objectives: The most commonly employed speech processing strategies in cochlear implants (CIs) only extract and encode amplitude modulation (AM) in a limited number of frequency channels. proposed a novel speech processing strategy that encodes both ... ...

    Abstract Objectives: The most commonly employed speech processing strategies in cochlear implants (CIs) only extract and encode amplitude modulation (AM) in a limited number of frequency channels. proposed a novel speech processing strategy that encodes both frequency modulation (FM) and AM to improve CI performance. Using behavioral tests, they reported better speech, speaker, and tone recognition with this novel strategy than with the AM-alone strategy. Here, we used the scalp-recorded human frequency following responses (FFRs) to examine the differences in the neural representation of vocoded speech sounds with AM alone and AM + FM as the spectral and temporal cues were varied. Specifically, we were interested in determining whether the addition of FM to AM improved the neural representation of envelope periodicity (FFRENV) and temporal fine structure (FFRTFS), as reflected in the temporal pattern of the phase-locked neural activity generating the FFR.
    Design: FFRs were recorded from 13 normal-hearing, adult listeners in response to the original unprocessed stimulus (a synthetic diphthong /au/ with a 110-Hz fundamental frequency or F0 and a 250-msec duration) and the 2-, 4-, 8- and 16-channel sine vocoded versions of /au/ with AM alone and AM + FM. Temporal waveforms, autocorrelation analyses, fast Fourier Transform, and stimulus-response spectral correlations were used to analyze both the strength and fidelity of the neural representation of envelope periodicity (F0) and TFS (formant structure).
    Results: The periodicity strength in the FFRENV decreased more for the AM stimuli than for the relatively resilient AM + FM stimuli as the number of channels was increased. Regardless of the number of channels, a clear spectral peak of FFRENV was consistently observed at the stimulus F0 for all the AM + FM stimuli but not for the AM stimuli. Neural representation as revealed by the spectral correlation of FFRTFS was better for the AM + FM stimuli when compared to the AM stimuli. Neural representation of the time-varying formant-related harmonics as revealed by the spectral correlation was also better for the AM + FM stimuli as compared to the AM stimuli.
    Conclusions: These results are consistent with previously reported behavioral results and suggest that the AM + FM processing strategy elicited brainstem neural activity that better preserved periodicity, temporal fine structure, and time-varying spectral information than the AM processing strategy. The relatively more robust neural representation of AM + FM stimuli observed here likely contributes to the superior performance on speech, speaker, and tone recognition with the AM + FM processing strategy. Taken together, these results suggest that neural information preserved in the FFR may be used to evaluate signal processing strategies considered for CIs.
    MeSH term(s) Acoustic Stimulation ; Adult ; Cochlear Implantation ; Cochlear Implants ; Cues ; Humans ; Speech ; Speech Perception
    Language English
    Publishing date 2019-06-20
    Publishing country United States
    Document type Journal Article
    ZDB-ID 603093-2
    ISSN 1538-4667 ; 0196-0202
    ISSN (online) 1538-4667
    ISSN 0196-0202
    DOI 10.1097/AUD.0000000000000756
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Corrigendum to ''Language-experience plasticity in neural representation of changes in pitch salience'' [Brain Research 1637 (2016) 102-117].

    Krishnan, Ananthanarayan / Gandour, Jackson T / Suresh, Chandan H

    Brain research

    2016  Volume 1644, Page(s) 308

    Language English
    Publishing date 2016-08-01
    Publishing country Netherlands
    Document type Published Erratum
    ZDB-ID 1200-2
    ISSN 1872-6240 ; 0006-8993
    ISSN (online) 1872-6240
    ISSN 0006-8993
    DOI 10.1016/j.brainres.2016.05.004
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  9. Article ; Online: Differential sensitivity to changes in pitch acceleration in the auditory brainstem and cortex.

    Krishnan, Ananthanarayan / Suresh, Chandan H / Gandour, Jackson T

    Brain and language

    2017  Volume 169, Page(s) 22–27

    Abstract: ... as a function of language experience (Krishnan, Gandour, & Suresh, 2014). CPR and brainstem frequency following ...

    Abstract The cortical pitch-specific response (CPR) is differentially sensitive to pitch contours varying in rate of acceleration-time-variant Mandarin Tone2 (T2) versus constant, linear rising ramp (Linear)-as a function of language experience (Krishnan, Gandour, & Suresh, 2014). CPR and brainstem frequency following response (FFR) data were recorded concurrently from native Mandarin listeners using the same stimuli. Results showed that T2 elicited larger responses than Linear at both cortical and brainstem levels (CPR: Na-Pb, Pb-Nb; FFR). However, Pb-Nb exhibited a larger difference in magnitude between T2 and Linear than either Na-Pb or FFR. This finding highlights differential weighting of brain responses elicited by a specific temporal attribute of pitch. Consistent with the notion of a distributed, integrated hierarchical pitch processing network, temporal attributes of pitch are differentially weighted by subcortical and cortical level processing.
    MeSH term(s) Acoustic Stimulation ; Auditory Cortex/physiology ; Auditory Perception/physiology ; Brain Stem/physiology ; Electroencephalography ; Evoked Potentials, Auditory, Brain Stem/physiology ; Female ; Humans ; Language ; Male ; Pitch Perception/physiology ; Young Adult
    Language English
    Publishing date 2017-06
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 7448-2
    ISSN 1090-2155 ; 0093-934X
    ISSN (online) 1090-2155
    ISSN 0093-934X
    DOI 10.1016/j.bandl.2017.01.014
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  10. Article ; Online: Language experience-dependent advantage in pitch representation in the auditory cortex is limited to favorable signal-to-noise ratios.

    Suresh, Chandan H / Krishnan, Ananthanarayan / Gandour, Jackson T

    Hearing research

    2017  Volume 355, Page(s) 42–53

    Abstract: Long-term experience enhances neural representation of temporal attributes of pitch in the brainstem and auditory cortex in favorable listening conditions. Herein we examine whether cortical pitch mechanisms shaped by language experience are more ... ...

    Abstract Long-term experience enhances neural representation of temporal attributes of pitch in the brainstem and auditory cortex in favorable listening conditions. Herein we examine whether cortical pitch mechanisms shaped by language experience are more resilient to degradation in background noise, and exhibit greater binaural release from masking (BRM). Cortical pitch responses (CPR) were recorded from Mandarin- and English-speaking natives using a Mandarin word exhibiting a high rising pitch (/yi
    MeSH term(s) Acoustic Stimulation ; Acoustics ; Adult ; Auditory Cortex/physiology ; Brain Mapping/methods ; Cues ; Electroencephalography ; Female ; Hearing ; Humans ; Male ; Noise/adverse effects ; Perceptual Masking ; Phonetics ; Pitch Perception ; Reaction Time ; Signal-To-Noise Ratio ; Sound Spectrography ; Speech Acoustics ; Time Factors ; Voice Quality ; Young Adult
    Language English
    Publishing date 2017-09-14
    Publishing country Netherlands
    Document type Comparative Study ; Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 282629-x
    ISSN 1878-5891 ; 0378-5955
    ISSN (online) 1878-5891
    ISSN 0378-5955
    DOI 10.1016/j.heares.2017.09.006
    Database MEDical Literature Analysis and Retrieval System OnLINE

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