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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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Johnson TD, Gallagher AJ, Coulson S, Rangel LM. Network resonance and the auditory steady state response. Sci Rep 2024; 14:16799. [PMID: 39039107 PMCID: PMC11263589 DOI: 10.1038/s41598-024-66697-4] [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: 12/26/2023] [Accepted: 07/03/2024] [Indexed: 07/24/2024] Open
Abstract
The auditory steady state response (ASSR) arises when periodic sounds evoke stable responses in auditory networks that reflect the acoustic characteristics of the stimuli, such as the amplitude of the sound envelope. Larger for some stimulus rates than others, the ASSR in the human electroencephalogram (EEG) is notably maximal for sounds modulated in amplitude at 40 Hz. To investigate the local circuit underpinnings of the large ASSR to 40 Hz amplitude-modulated (AM) sounds, we acquired skull EEG and local field potential (LFP) recordings from primary auditory cortex (A1) in the rat during the presentation of 20, 30, 40, 50, and 80 Hz AM tones. 40 Hz AM tones elicited the largest ASSR from the EEG acquired above auditory cortex and the LFP acquired from each cortical layer in A1. The large ASSR in the EEG to 40 Hz AM tones was not due to larger instantaneous amplitude of the signals or to greater phase alignment of the LFP across the cortical layers. Instead, it resulted from decreased latency variability (or enhanced temporal consistency) of the 40 Hz response. Statistical models indicate the EEG signal was best predicted by LFPs in either the most superficial or deep cortical layers, suggesting deep layer coordinators of the ASSR. Overall, our results indicate that the recruitment of non-uniform but more temporally consistent responses across A1 layers underlie the larger ASSR to amplitude-modulated tones at 40 Hz.
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Affiliation(s)
- Teryn D Johnson
- Department of Cognitive Science, University of California San Diego, La Jolla, 92093, USA
| | - Austin J Gallagher
- Department of Cognitive Science, University of California San Diego, La Jolla, 92093, USA
| | - Seana Coulson
- Department of Cognitive Science, University of California San Diego, La Jolla, 92093, USA
| | - Lara M Rangel
- Department of Cognitive Science, University of California San Diego, La Jolla, 92093, USA.
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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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DeJonckere PH, Lebacq J. Asymmetry of Occupational Noise Induced Hearing Loss: An Electrophysiological Approach. Int Arch Otorhinolaryngol 2023; 27:e499-e510. [PMID: 37564477 PMCID: PMC10411239 DOI: 10.1055/s-0042-1750766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 05/15/2022] [Indexed: 03/31/2023] Open
Abstract
Introduction The question as to whether occupational noise exposure causes symmetrical or asymmetrical hearing loss is still controversial and incompletely understood. Objective Two electrophysiological methods (cortical evoked response audiometry: CERA and auditory steady state responses: ASSR) were used to address this issue. Method 156 subjects with a well-documented history of noise exposure, a wide range of noise induced hearing loss (NIHL) and without middle ear pathology underwent both a CERA and an ASSR examination in the context of an exhaustive medicolegal expert assessment intended for possible compensation. Results Whatever the method (CERA or ASSR), the average electrophysiological hearing thresholds (1-2-3 kHz) are significantly worse in the left ear. The right - left differences in CERA and ASSR thresholds are strongly correlated with each other. No significant effect of frequency is found. No correlation is observed between right - left differences in hearing thresholds and either age or degree of hearing loss. Conclusion In NIHL, there is an actual average right - left difference of about 2.23 dB, i.e., 3.2%, the left ear being more impaired.
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Affiliation(s)
| | - Jean Lebacq
- University of Louvain, Neurosciences, Brussels, Belgium
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Comparison of non-invasive, scalp-recorded auditory steady-state responses in humans, rhesus monkeys, and common marmosets. Sci Rep 2022; 12:9210. [PMID: 35654875 PMCID: PMC9163194 DOI: 10.1038/s41598-022-13228-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 05/23/2022] [Indexed: 12/27/2022] Open
Abstract
Auditory steady-state responses (ASSRs) are basic neural responses used to probe the ability of auditory circuits to produce synchronous activity to repetitive external stimulation. Reduced ASSR has been observed in patients with schizophrenia, especially at 40 Hz. Although ASSR is a translatable biomarker with a potential both in animal models and patients with schizophrenia, little is known about the features of ASSR in monkeys. Herein, we recorded the ASSR from humans, rhesus monkeys, and marmosets using the same method to directly compare the characteristics of ASSRs among the species. We used auditory trains on a wide range of frequencies to investigate the suitable frequency for ASSRs induction, because monkeys usually use stimulus frequency ranges different from humans for vocalization. We found that monkeys and marmosets also show auditory event-related potentials and phase-locking activity in gamma-frequency trains, although the optimal frequency with the best synchronization differed among these species. These results suggest that the ASSR could be a useful translational, cross-species biomarker to examine the generation of gamma-band synchronization in nonhuman primate models of schizophrenia.
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DeJonckere P, Lebacq J. The comparison of auditory behavioral and evoked potential responses (steady state and cortical) in subjects with occupational noise-induced hearing loss. J Otol 2021; 16:242-251. [PMID: 34548871 PMCID: PMC8438636 DOI: 10.1016/j.joto.2021.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/13/2021] [Accepted: 05/23/2021] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE To define difference scores between PTA, ASSR and CERA thresholds in subjects with occupational NIHL. DESIGN 44 subjects undergoing a medico-legal expert assessment for occupational NIHL and fulfilling criteria of reliability were considered. Assessment included: PTA, 40 Hz binaural multiple ASSR and CERA (1-2-3 kHz). RESULTS The respective average difference scores (ASSR - PTA) for 1, 2 and 3 kHz are 13.01 (SD 10.19) dB, 12.72 (SD 8.81) dB and 10.38 (SD 8.19) dB. The average (CERA - ASSR) difference scores are 1.25 (SD 14.63) dB for 1 kHz (NS), 2.73 (SD 13.03) dB for 2 kHz (NS) and 4.51 (SD 12.18) dB for 3 kHz. The correlation between PTA and ASSR (0.82) is significantly stronger than that between PTA and CERA (0.71). In a given subject, PTA thresholds are nearly always lower (i.e., better) than ASSR thresholds, whatever the frequency (1-2-3 kHz) and the side (right - left). A significant negative correlation is found between the difference score (ASSR - PTA) and the degree of hearing loss. CONCLUSION ASSR outperforms CERA in a medicolegal context, although overestimating the behavioral thresholds by 10-13 dB.
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Affiliation(s)
- P.H. DeJonckere
- Federal Agency for Occupational Risks, Avenue de l’Astronomie, 1, B-1210, Bruxelles, Brussels, Belgium
| | - J. Lebacq
- Institute of Neurosciences, University of Louvain, Pasteur, Avenue Mounier, 53, B-1200, Bruxelles, Brussels, Belgium
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Objective frequency-specific hearing thresholds definition for medicolegal purposes in case of occupational NIHL: ASSR outperforms CERA. J Otol 2021; 16:210-219. [PMID: 34548866 PMCID: PMC8438637 DOI: 10.1016/j.joto.2021.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 01/13/2021] [Accepted: 02/18/2021] [Indexed: 11/24/2022] Open
Abstract
Audiological use of the 40 Hz-ASSR (auditory steady state responses) could be valuable for objectively estimating the frequency-specific threshold in adults undergoing an expertise examination for medicolegal and/or compensation purposes. The present prospective study was set up to clarify the relationship between the thresholds obtained by cortical evoked response audiometry (CERA) and by 40 Hz-ASSR, in the same ears, within a large homogeneous sample of 164 subjects (328 ears) with NIHL and well documented exposure to noise. All these subjects claimed financial compensation for occupational NIHL, and there was a suspicion of exaggeration of the reported NIHLs. ASSR thresholds show a good correlation with the CERA thresholds. However, a systematic shift is noticed, ASSR thresholds being on average (1–2 – 3 kHz) 4.38 dB lower (i.e. showing less hearing loss) than CERA thresholds. Moreover, the binaural multiple ASSR technique allows a considerable time gain when compared to the CERA.
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Zhang L, Liu S, Liu X, Zhang B, An X, Ming D. Emotional Arousal and Valence Jointly Modulate the Auditory Response: A 40-Hz ASSR Study. IEEE Trans Neural Syst Rehabil Eng 2021; 29:1150-1157. [PMID: 34110997 DOI: 10.1109/tnsre.2021.3088257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Emotion is defined as a response to external stimuli and internal mental representations. It has been characterized as a multidimensional concept, primarily comprising two dimensions: valence and arousal. Existing studies have demonstrated that emotional experience exerts a powerful impact on auditory processing in terms of valence. However, it has also been shown that while negative emotion can improve auditory perception in healthy subjects, patients with depression show deficits in auditory perception. We thus speculated that both arousal and valence jointly modulate auditory perception. To examine the emotion-driven effects on the auditory response, we induced positive, negative, and neutral emotional states in healthy subjects and collected auditory steady-state response (ASSR) evoked by a 40-Hz chirp sound. We calculated peak-to-peak amplitude (PPA) and event-related spectral perturbation (ERSP) of evoked ASSRs and observed that the positive emotions significantly enhanced brain responses to auditory stimuli (p < 0.001), but that ASSRs in a negative state were not significantly enhanced compared with the neutral state. Subsequently, regression analysis showed a significant positive multiple linear relationship between the PPA and ratings of two emotional dimensions, indicating that arousal and valence jointly regulated the auditory cortex's synchronous oscillation, rather than the valence in isolation, offering the potential to clarify the conflicting results surrounding the role of negative emotions in auditory responses. Because depression is generally characterized by low arousal and low valence in actual life, whereas the negative emotion evoked under laboratory conditions is always with low valence but high arousal.
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Koerner TK, Muralimanohar RK, Gallun FJ, Billings CJ. Age-Related Deficits in Electrophysiological and Behavioral Measures of Binaural Temporal Processing. Front Neurosci 2020; 14:578566. [PMID: 33192263 PMCID: PMC7654338 DOI: 10.3389/fnins.2020.578566] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/25/2020] [Indexed: 01/15/2023] Open
Abstract
Binaural processing, particularly the processing of interaural phase differences, is important for sound localization and speech understanding in background noise. Age has been shown to impact the neural encoding and perception of these binaural temporal cues even in individuals with clinically normal hearing sensitivity. This work used a new electrophysiological response, called the interaural phase modulation-following response (IPM-FR), to examine the effects of age on the neural encoding of interaural phase difference cues. Relationships between neural recordings and performance on several behavioral measures of binaural processing were used to determine whether the IPM-FR is predictive of interaural phase difference sensitivity and functional speech understanding deficits. Behavioral binaural frequency modulation detection thresholds were measured to assess sensitivity to interaural phase differences while spatial release-from-masking thresholds were used to assess speech understanding abilities in spatialized noise. Thirty adults between the ages of 35 to 74 years with normal low-frequency hearing thresholds were used in this study. Data showed that older participants had weaker neural responses to the interaural phase difference cue and were less able to take advantage of binaural cues for speech understanding compared to younger participants. Results also showed that the IPM-FR was predictive of performance on the binaural frequency modulation detection task, but not on the spatial release-from-masking task after accounting the effects of age. These results confirm previous work that showed that the IPM-FR reflects age-related declines in binaural temporal processing and provide further evidence that this response may represent a useful objective tool for assessing binaural function. However, further research is needed to understand how the IPM-FR is related to speech understanding abilities.
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Affiliation(s)
- Tess K. Koerner
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
| | - Ramesh Kumar Muralimanohar
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
- Department of Otolaryngology/Head and Neck Surgery, Oregon Health & Science University, Portland, OR, United States
| | - Frederick J. Gallun
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
- Department of Otolaryngology/Head and Neck Surgery, Oregon Health & Science University, Portland, OR, United States
| | - Curtis J. Billings
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, Portland, OR, United States
- Department of Otolaryngology/Head and Neck Surgery, Oregon Health & Science University, Portland, OR, United States
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Auditory cortex responses to interaural time differences in the envelope of low-frequency sound, recorded with MEG in young and older listeners. Hear Res 2018; 370:22-39. [PMID: 30265860 DOI: 10.1016/j.heares.2018.09.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 08/31/2018] [Accepted: 09/03/2018] [Indexed: 11/21/2022]
Abstract
Interaural time and intensity differences (ITD and IID) are important cues in binaural hearing and allow for sound localization, improving speech understanding in noise and reverberation, and integrating sound sources in the auditory scene. Whereas previous research showed that the upper-frequency limit for ITD detection in the fine structure of sound declines in aging, the processing of envelope ITD in low-frequency amplitude modulated (AM) sound and the related brain responses are less understood. This study investigated the cortical processing of envelope ITD and compared the results with previous findings about the fine-structure ITD. In two experiments, participants listened to 40-Hz AM tones containing sudden changes in the envelope ITD. Multiple MEG responses were analyzed, including the auditory evoked N1 responses, elicited both by sound onsets and ITD changes, and 40-Hz responses, elicited by the AM. The first experiment with healthy young adults revealed a substantial decline in the magnitudes of the ITD change N1 response, and the 40-Hz phase resets at higher carrier frequencies, suggesting a similar frequency characteristic as observed for fine structure ITD. The amplitude of the 40-Hz ASSR declined only gradually with increasing carrier frequency, and it was excluded as a confounding factor in the decline in the ITD response. Larger responses to outward ITD changes than inward changes, here first reported for envelope ITD, were another characteristics that were similar to fine-structure ITD. A second experiment with groups of young and older listeners examined the effects of aging and concurrent noise on the cortical envelope ITD responses. One important research question was, whether binaural cues are accessible in noise. Behavioural tests showed an age-related hearing loss in the older group and decreased performance in envelope ITD detection and speech-in-noise (SIN) understanding. Binaural hearing and SIN performance were correlated with one other, but not with hearing loss. The frequency limit for envelope ITD was reduced in older listeners similarly as previously found for fine structure ITD, and older listeners were more susceptible to concurrent multi-talker noise. The similarities between responses to envelope ITD and to fine structure ITD suggest that a common cortical code exists for the envelope and fine structure ITD. The dependency on the carrier frequency suggests that envelope ITD processing at the subcortical level requires stimulus phase locking, which might be reduced in aging.
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Abstract
OBJECTIVES Auditory stimuli modulated by modulation frequencies within the 30 to 50 Hz region evoke auditory steady state responses (ASSRs) with high signal to noise ratios in adults, and can be used to determine the frequency-specific hearing thresholds of adults who are unable to give behavioral feedback reliably. To measure ASSRs as efficiently as possible a multiple stimulus paradigm can be used, stimulating both ears simultaneously. The response strength of 30 to 50Hz ASSRs is, however, affected when both ears are stimulated simultaneously. The aim of the present study is to gain insight in the measurement efficiency of 30 to 50 Hz ASSRs evoked with a 2-ear stimulation paradigm, by systematically investigating the binaural interaction effects of 30 to 50 Hz ASSRs in normal-hearing adults. DESIGN ASSRs were obtained with a 64-channel EEG system in 23 normal-hearing adults. All participants participated in one diotic, multiple dichotic, and multiple monaural conditions. Stimuli consisted of a modulated one-octave noise band, centered at 1 kHz, and presented at 70 dB SPL. The diotic condition contained 40 Hz modulated stimuli presented to both ears. In the dichotic conditions, the modulation frequency of the left ear stimulus was kept constant at 40 Hz, while the stimulus at the right ear was either the unmodulated or modulated carrier. In case of the modulated carrier, the modulation frequency varied between 30 and 50 Hz in steps of 2 Hz across conditions. The monaural conditions consisted of all stimuli included in the diotic and dichotic conditions. RESULTS Modulation frequencies ≥36 Hz resulted in prominent ASSRs in all participants for the monaural conditions. A significant enhancement effect was observed (average: ~3 dB) in the diotic condition, whereas a significant reduction effect was observed in the dichotic conditions. There was no distinct effect of the temporal characteristics of the stimuli on the amount of reduction. The attenuation was in 33% of the cases >3 dB for ASSRs evoked with modulation frequencies ≥40 Hz and 50% for ASSRs evoked with modulation frequencies ≤36 Hz. CONCLUSIONS Binaural interaction effects as observed in the diotic condition are similar to the binaural interaction effects of middle latency responses as reported in the literature, suggesting that these responses share a same underlying mechanism. Our data also indicated that 30 to 50 Hz ASSRs are attenuated when presented dichotically and that this attenuation is independent of the stimulus characteristics as used in the present study. These findings are important as they give insight in how binaural interaction affects the measurement efficiency. The 2-ear stimulation paradigm of the present study was, for the most optimal modulation frequencies (i.e., ≥40 Hz), more efficient than a 1-ear sequential stimulation paradigm in 66% of the cases.
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Spatiotemporal reconstruction of auditory steady-state responses to acoustic amplitude modulations: Potential sources beyond the auditory pathway. Neuroimage 2017; 148:240-253. [DOI: 10.1016/j.neuroimage.2017.01.032] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 01/13/2017] [Indexed: 11/23/2022] Open
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Gransier R, Deprez H, Hofmann M, Moonen M, van Wieringen A, Wouters J. Auditory steady-state responses in cochlear implant users: Effect of modulation frequency and stimulation artifacts. Hear Res 2016; 335:149-160. [PMID: 26994660 DOI: 10.1016/j.heares.2016.03.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 03/04/2016] [Accepted: 03/14/2016] [Indexed: 11/29/2022]
Abstract
Previous studies have shown that objective measures based on stimulation with low-rate pulse trains fail to predict the threshold levels of cochlear implant (CI) users for high-rate pulse trains, as used in clinical devices. Electrically evoked auditory steady-state responses (EASSRs) can be elicited by modulated high-rate pulse trains, and can potentially be used to objectively determine threshold levels of CI users. The responsiveness of the auditory pathway of profoundly hearing-impaired CI users to modulation frequencies is, however, not known. In the present study we investigated the responsiveness of the auditory pathway of CI users to a monopolar 500 pulses per second (pps) pulse train modulated between 1 and 100 Hz. EASSRs to forty-three modulation frequencies, elicited at the subject's maximum comfort level, were recorded by means of electroencephalography. Stimulation artifacts were removed by a linear interpolation between a pre- and post-stimulus sample (i.e., blanking). The phase delay across modulation frequencies was used to differentiate between the neural response and a possible residual stimulation artifact after blanking. Stimulation artifacts were longer than the inter-pulse interval of the 500pps pulse train for recording electrodes ipsilateral to the CI. As a result the stimulation artifacts could not be removed by artifact removal on the bases of linear interpolation for recording electrodes ipsilateral to the CI. However, artifact-free responses could be obtained in all subjects from recording electrodes contralateral to the CI, when subject specific reference electrodes (Cz or Fpz) were used. EASSRs to modulation frequencies within the 30-50 Hz range resulted in significant responses in all subjects. Only a small number of significant responses could be obtained, during a measurement period of 5 min, that originate from the brain stem (i.e., modulation frequencies in the 80-100 Hz range). This reduced synchronized activity of brain stem responses in long-term severely-hearing impaired CI users could be an attribute of processes associated with long-term hearing impairment and/or electrical stimulation.
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Affiliation(s)
- Robin Gransier
- ExpORL, Dept. of Neurosciences, KU Leuven, Herestraat 49 bus 721, 3000 Leuven, Belgium.
| | - Hanne Deprez
- ExpORL, Dept. of Neurosciences, KU Leuven, Herestraat 49 bus 721, 3000 Leuven, Belgium; STADIUS, Dept. of Electrical Engineering (ESAT), KU Leuven, Kasteelpark Arenberg 10, 3001 Leuven, Belgium
| | - Michael Hofmann
- ExpORL, Dept. of Neurosciences, KU Leuven, Herestraat 49 bus 721, 3000 Leuven, Belgium
| | - Marc Moonen
- STADIUS, Dept. of Electrical Engineering (ESAT), KU Leuven, Kasteelpark Arenberg 10, 3001 Leuven, Belgium
| | - Astrid van Wieringen
- 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
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Tlumak AI, Durrant JD, Delgado RE. The Effect of Advancing Age on Auditory Middle- and Long-Latency Evoked Potentials Using a Steady-State-Response Approach. Am J Audiol 2015; 24:494-507. [PMID: 26650518 DOI: 10.1044/2015_aja-15-0036] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Accepted: 08/14/2015] [Indexed: 11/09/2022] Open
Abstract
PURPOSE The purpose of the study was to objectively detect age-specific changes that occur in equivalent auditory steady-state responses (ASSRs), corresponding to transient middle- and long-latency auditory evoked potentials as a function of repetition rate and advancing age. METHOD The study included 48 healthy hearing adults who were equally divided into 3 groups by age: 20-39, 40-59, and 60-79 years. ASSRs were recorded at 7 repetition rates from 40 down to 0.75 Hz, elicited by trains of repeated tone burst stimuli. RESULTS Temporal analysis of middle- and long-latency equivalent ASSRs revealed no appreciable changes in the magnitudes of the response across the age groups. Likewise, the spectral analysis revealed that advancing age did not substantially affect the spectral content of the response at each repetition rate. Furthermore, the harmonic sum was not significantly different across the 3 age groups, between the younger adults versus the combined Older Group Sample 1 and Sample 2, and between the two extreme age groups (i.e., 20-39 vs. 60-79) for the middle- and long-latency equivalent ASSRs. CONCLUSION Advancing age has no effect on the long-latency equivalent ASSRs; however, aging does affect the middle-latency equivalent ASSRs when the mean age difference is ≥ 40 years.
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Llinás RR. Intrinsic electrical properties of mammalian neurons and CNS function: a historical perspective. Front Cell Neurosci 2014; 8:320. [PMID: 25408634 PMCID: PMC4219458 DOI: 10.3389/fncel.2014.00320] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Accepted: 09/23/2014] [Indexed: 11/23/2022] Open
Abstract
This brief review summarizes work done in mammalian neuroscience concerning the intrinsic electrophysiological properties of four neuronal types; Cerebellar Purkinje cells, inferior olivary cells, thalamic cells, and some cortical interneurons. It is a personal perspective addressing an interesting time in neuroscience when the reflex view of brain function, as the paradigm to understand global neuroscience, began to be modified toward one in which sensory input modulates rather than dictates brain function. The perspective of the paper is not a comprehensive description of the intrinsic electrical properties of all nerve cells but rather addresses a set of cell types that provide indicative examples of mechanisms that modulate brain function.
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Affiliation(s)
- Rodolfo R Llinás
- Department of Neuroscience and Physiology, New York University School of Medicine New York, NY, USA
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Usubuchi H, Kawase T, Kanno A, Yahata I, Miyazaki H, Nakasato N, Kawashima R, Katori Y. Effects of contralateral noise on the 20-Hz auditory steady state response--magnetoencephalography study. PLoS One 2014; 9:e99457. [PMID: 24915061 PMCID: PMC4051787 DOI: 10.1371/journal.pone.0099457] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 05/15/2014] [Indexed: 11/18/2022] Open
Abstract
The auditory steady state response (ASSR) is an oscillatory brain response, which is phase locked to the rhythm of an auditory stimulus. ASSRs have been recorded in response to a wide frequency range of modulation and/or repetition, but the physiological features of the ASSRs are somewhat different depending on the modulation frequency. Recently, the 20-Hz ASSR has been emphasized in clinical examinations, especially in the area of psychiatry. However, little is known about the physiological properties of the 20-Hz ASSR, compared to those of the 40-Hz and 80-Hz ASSRs. The effects of contralateral noise on the ASSR are known to depend on the modulation frequency to evoke ASSR. However, the effects of contralateral noise on the 20-Hz ASSR are not known. Here we assessed the effects of contralateral white noise at a level of 70 dB SPL on the 20-Hz and 40-Hz ASSRs using a helmet-shaped magnetoencephalography system in 9 healthy volunteers (8 males and 1 female, mean age 31.2 years). The ASSRs were elicited by monaural 1000-Hz 5-s tone bursts amplitude-modulated at 20 and 39 Hz and presented at 80 dB SPL. Contralateral noise caused significant suppression of both the 20-Hz and 40-Hz ASSRs, although suppression was significantly smaller for the 20-Hz ASSRs than the 40-Hz ASSRs. Moreover, the greatest suppression of both 20-Hz and 40-Hz ASSRs occurred in the right hemisphere when stimuli were presented to the right ear with contralateral noise. The present study newly showed that 20-Hz ASSRs are suppressed by contralateral noise, which may be important both for characterization of the 20-Hz ASSR and for interpretation in clinical situations. Physicians must be aware that the 20-Hz ASSR is significantly suppressed by sound (e.g. masking noise or binaural stimulation) applied to the contralateral ear.
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Affiliation(s)
- Hajime Usubuchi
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Tetsuaki Kawase
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Laboratory of Rehabilitative Auditory Science, Tohoku University Graduate School of Biomedical Engineering, Sendai, Miyagi, Japan
- Department of Audiology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- * E-mail:
| | - Akitake Kanno
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan
| | - Izumi Yahata
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Hiromitsu Miyazaki
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Nobukazu Nakasato
- Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Department of Electromagnetic Neurophysiology, Smart Ageing International Research Center, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan
| | - Ryuta Kawashima
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan
| | - Yukio Katori
- Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
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Nozaradan S, Zerouali Y, Peretz I, Mouraux A. Capturing with EEG the neural entrainment and coupling underlying sensorimotor synchronization to the beat. ACTA ACUST UNITED AC 2013; 25:736-47. [PMID: 24108804 DOI: 10.1093/cercor/bht261] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Synchronizing movements with rhythmic inputs requires tight coupling of sensory and motor neural processes. Here, using a novel approach based on the recording of steady-state-evoked potentials (SS-EPs), we examine how distant brain areas supporting these processes coordinate their dynamics. The electroencephalogram was recorded while subjects listened to a 2.4-Hz auditory beat and tapped their hand on every second beat. When subjects tapped to the beat, the EEG was characterized by a 2.4-Hz SS-EP compatible with beat-related entrainment and a 1.2-Hz SS-EP compatible with movement-related entrainment, based on the results of source analysis. Most importantly, when compared with passive listening of the beat, we found evidence suggesting an interaction between sensory- and motor-related activities when subjects tapped to the beat, in the form of (1) additional SS-EP appearing at 3.6 Hz, compatible with a nonlinear product of sensorimotor integration; (2) phase coupling of beat- and movement-related activities; and (3) selective enhancement of beat-related activities over the hemisphere contralateral to the tapping, suggesting a top-down effect of movement-related activities on auditory beat processing. Taken together, our results are compatible with the view that rhythmic sensorimotor synchronization is supported by a dynamic coupling of sensory and motor related activities.
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Affiliation(s)
- Sylvie Nozaradan
- Institute of Neuroscience (IONS), Université catholique de Louvain (UCL), Belgium International Laboratory for Brain, Music and Sound Research (BRAMS), Université de Montréal, Canada
| | - Younes Zerouali
- Ecole de Technologie Supérieure, Université de Montréal, Canada
| | - Isabelle Peretz
- International Laboratory for Brain, Music and Sound Research (BRAMS), Université de Montréal, Canada
| | - André Mouraux
- Institute of Neuroscience (IONS), Université catholique de Louvain (UCL), Belgium
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Kuriki S, Yokosawa K, Takahashi M. Neural representation of scale illusion: magnetoencephalographic study on the auditory illusion induced by distinctive tone sequences in the two ears. PLoS One 2013; 8:e75990. [PMID: 24086676 PMCID: PMC3781093 DOI: 10.1371/journal.pone.0075990] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 08/22/2013] [Indexed: 11/19/2022] Open
Abstract
The auditory illusory perception “scale illusion” occurs when a tone of ascending scale is presented in one ear, a tone of descending scale is presented simultaneously in the other ear, and vice versa. Most listeners hear illusory percepts of smooth pitch contours of the higher half of the scale in the right ear and the lower half in the left ear. Little is known about neural processes underlying the scale illusion. In this magnetoencephalographic study, we recorded steady-state responses to amplitude-modulated short tones having illusion-inducing pitch sequences, where the sound level of the modulated tones was manipulated to decrease monotonically with increase in pitch. The steady-state responses were decomposed into right- and left-sound components by means of separate modulation frequencies. It was found that the time course of the magnitude of response components of illusion-perceiving listeners was significantly correlated with smooth pitch contour of illusory percepts and that the time course of response components of stimulus-perceiving listeners was significantly correlated with discontinuous pitch contour of stimulus percepts in addition to the contour of illusory percepts. The results suggest that the percept of illusory pitch sequence was represented in the neural activity in or near the primary auditory cortex, i.e., the site of generation of auditory steady-state response, and that perception of scale illusion is maintained by automatic low-level processing.
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Affiliation(s)
- Shinya Kuriki
- Research Center for Science and Technology, Tokyo Denki University, Inzai, Japan
- * E-mail:
| | - Koichi Yokosawa
- Graduate School of Health Science, Hokkaido University, Sapporo, Japan
| | - Makoto Takahashi
- Graduate School of Information Science and Technology, Sapporo, Japan
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Kuriki S, Kobayashi Y, Kobayashi T, Tanaka K, Uchikawa Y. Steady-state MEG responses elicited by a sequence of amplitude-modulated short tones of different carrier frequencies. Hear Res 2013; 296:25-35. [PMID: 23174483 DOI: 10.1016/j.heares.2012.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 10/28/2012] [Accepted: 11/05/2012] [Indexed: 10/27/2022]
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20
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Nozaradan S, Peretz I, Mouraux A. Steady-state evoked potentials as an index of multisensory temporal binding. Neuroimage 2011; 60:21-8. [PMID: 22155324 DOI: 10.1016/j.neuroimage.2011.11.065] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 11/10/2011] [Accepted: 11/22/2011] [Indexed: 11/28/2022] Open
Abstract
Temporal congruency promotes perceptual binding of multisensory inputs. Here, we used EEG frequency-tagging to track cortical activities elicited by auditory and visual inputs separately, in the form of steady-state evoked potentials (SS-EPs). We tested whether SS-EPs could reveal a dynamic coupling of cortical activities related to the binding of auditory and visual inputs conveying synchronous vs. non-synchronous temporal periodicities, or beats. The temporally congruent audiovisual condition elicited markedly enhanced auditory and visual SS-EPs, as compared to the incongruent condition. Furthermore, an increased inter-trial phase coherence of both SS-EPs was observed in that condition. Taken together, these observations indicate that temporal congruency enhances the processing of multisensory inputs at sensory-specific stages of cortical processing, possibly through a dynamic binding by synchrony of the elicited activities and/or improved dynamic attending. Moreover, we show that EEG frequency-tagging with SS-EPs constitutes an effective tool to explore the neural dynamics of multisensory integration in the human brain.
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Affiliation(s)
- Sylvie Nozaradan
- Institute of Neuroscience (Ions), Université catholique de Louvain (UCL), Belgium
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21
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Arrondo G, Alegre M, Sepulcre J, Iriarte J, Artieda J, Villoslada P. Abnormalities in brain synchronization are correlated with cognitive impairment in multiple sclerosis. Mult Scler 2009; 15:509-16. [PMID: 19282416 DOI: 10.1177/1352458508101321] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Cognitive functions are supported by brain networks and they are highly dependent on the integrity of long white matter tracts that mediate the information flow between such distant cortical areas. Brain damage in multiple sclerosis (MS) may produce cognitive impairment by preferentially damaging these tracts, thereby impairing brain synchrony. Auditory amplitude modulation following responses (AMFR), are oscillatory steady-state responses to rhythmic auditory stimuli that indirectly measure brain synchrony. OBJECTIVE To study the effect of MS lesions in brain synchrony and its relationship with cognitive function. METHODS We assessed the correlation between cognitive performance, as assessed with the brief repeatable battery-neuropsychology (BRB-N), and the AMFR in a group of 27 MS patients and 22 healthy controls. RESULTS The maximal AMFR frequency - but not the amplitude - in the 30-60 Hz range was lower in patients with cognitive impairment than in patients with no cognitive impairment or the healthy controls (39.79 Hz, 43.85 Hz, and 43.84 Hz, respectively, P < 0.05). Indeed, the frequency of the AMFR was negatively correlated with the scores obtained in verbal memory, attention, and executive function. The multiple regression analysis indicates that the AMFR was the best predictor of the BRB-N scores after controlling for potential confounding factors such as age, education, disability, and years of disease evolution. CONCLUSIONS These results suggest that the loss of synchronization in different central nervous system (CNS) pathways caused by demyelinating lesions might involve both the slowing of brain oscillatory activity and less efficient cognitive processing.
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Affiliation(s)
- G Arrondo
- Department of Neurosciences, CIMA University of Navarra, Pamplona, Spain
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22
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Poulsen C, Picton TW, Paus T. Age-related changes in transient and oscillatory brain responses to auditory stimulation during early adolescence. Dev Sci 2009; 12:220-35. [DOI: 10.1111/j.1467-7687.2008.00760.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Poulsen C, Picton TW, Paus T. Age-related changes in transient and oscillatory brain responses to auditory stimulation in healthy adults 19-45 years old. Cereb Cortex 2006; 17:1454-67. [PMID: 16916887 DOI: 10.1093/cercor/bhl056] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The capacity of the human cerebral cortex to track fast temporal changes in auditory stimuli is related to the development of language in children and to deficits in speech perception in the elderly. Although maturation of temporal processing in children and its deterioration in the elderly has been investigated previously, little is known about naturally occurring changes in auditory temporal processing between these limits. The present study examined age-related (19-45 years) changes in 3 electrophysiological measures of auditory processing: 1) the late transient auditory evoked potentials to tone onset, 2) the auditory steady-state response (ASSR) to a 40-Hz frequency-modulated tone, and 3) the envelope following response (EFR) to sweeps of amplitude-modulated white noise from 10 to 100 Hz. With increasing age, the latency of the auditory P1-N1 complex decreased, the oscillatory (ASSR) response became larger and more stable, and the resonant peak of the EFR increased from 38 Hz at 19 years to 46 Hz at 45 years. Source analysis localized these changes to the auditory regions of the temporal lobe. These results indicate persistent adaptation of cortical auditory processes into middle adulthood. We speculate that experience-driven myelination and/or refinement of inhibitory circuits may underlie these changes.
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Affiliation(s)
- Catherine Poulsen
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, Canada.
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Pastor MA, Thut G, Pascual-Leone A. Modulation of steady-state auditory evoked potentials by cerebellar rTMS. Exp Brain Res 2006; 175:702-9. [PMID: 16826412 DOI: 10.1007/s00221-006-0588-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Accepted: 06/02/2006] [Indexed: 10/24/2022]
Abstract
Steady-state auditory evoked responses (SSAER) obtained via electroencephalography (EEG) co-vary in amplitude with blood flow changes in the auditory area of the cerebellum. The aim of the present EEG study was to probe the cerebellar role in the control of such SSAER. For this purpose, we investigated changes in SSAERs due to transient disruption of the cerebellar hemisphere by repetitive transcranial magnetic stimulation (rTMS). SSAERs to click-trains of three different frequencies in the gamma-band (32, 40 and 47 Hz) were recorded from 45 scalp electrodes in six healthy volunteers immediately after 1-Hz rTMS and compared to baseline SSAERs assessed prior to magnetic stimulation. Cerebellar rTMS contralateral to the stimulated ear significantly reduced the amplitude of steady-state responses to 40-Hz click-trains and showed a tendency to reduce the amplitude to 32-Hz click-trains. No effects were observed for 47-Hz click-trains, nor for magnetic stimulation of the cerebellum ipsilateral to auditory stimulation or after sham stimulation. Our results suggest that interference with cerebellar output by rTMS modifies functional activity associated with cortical auditory processing. The finding of maximum effects on 40-Hz SSAERs provides support to the notion that the cerebellum is part of a distributed network involved in the regulation of cortical oscillatory activity and points at some frequency-specificity for the control of auditory-driven neuronal oscillations.
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Affiliation(s)
- Maria A Pastor
- Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
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25
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Vander Werff KR, Brown CJ. Effect of Audiometric Configuration on Threshold and Suprathreshold Auditory Steady-State Responses. Ear Hear 2005; 26:310-26. [PMID: 15937412 DOI: 10.1097/00003446-200506000-00007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The purpose of this study was to examine the correlation between auditory steady-state response (ASSR) thresholds and behavioral thresholds in hearing-impaired adults with two common audiometric configurations. A second goal was to compare suprathreshold ASSR growth functions in these two subject groups and to determine whether these growth functions could be used clinically to improve threshold estimation. DESIGN Thirty adults participated, including 10 subjects with normal hearing, 10 subjects with flat moderately severe sensorineural hearing loss, and 10 subjects with sloping high-frequency sensorineural hearing loss. The accuracy of ASSR threshold estimations for the frequencies of 500, 1000, 2000, and 4000 Hz was compared across groups. In addition, ASSRs were recorded at multiple suprathreshold intensity levels, and the growth of the response was compared across subject groups. RESULTS ASSR and behavioral thresholds were strongly correlated across all subjects, with no significant difference by audiometric configuration. Slightly poorer correlations were obtained in the normal-hearing subjects than in hearing-impaired subjects and for the 500-Hz test frequency compared with the higher stimulus frequencies. Subtraction and regression methods for predicting behavioral thresholds from ASSR thresholds were equally accurate. Suprathreshold amplitude growth was variable among individuals, but mean growth functions showed steeper slopes in hearing-impaired subjects than in normal-hearing subjects, particularly for the higher frequencies (2000 to 4000 Hz). However, there was not a significant difference in the slopes of amplitude growth functions between subjects with sloping versus flat audiometric configurations for these frequencies, and estimation of threshold from suprathreshold ASSR amplitude growth functions was not advantageous. CONCLUSIONS ASSR thresholds accurately predicted behavioral threshold equally well for flat or sloping audiometric configurations. The accuracy of threshold estimation for either audiometric configuration and the similar growth function slopes may suggest that there is little spread of activation to neighboring regions of the cochlea when using multiple 100% AM stimuli in subjects with moderately sloping losses. The small amplitude of the ASSR response and individual variability may make threshold estimation based on extrapolation from suprathreshold ASSR responses impractical.
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Affiliation(s)
- Kathy R Vander Werff
- Department of Speech Pathology and Audiology, University of Iowa, Iowa City, Iowa, USA
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26
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Schwarz DWF, Taylor P. Human auditory steady state responses to binaural and monaural beats. Clin Neurophysiol 2005; 116:658-68. [PMID: 15721080 DOI: 10.1016/j.clinph.2004.09.014] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/18/2004] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Binaural beat sensations depend upon a central combination of two different temporally encoded tones, separately presented to the two ears. We tested the feasibility to record an auditory steady state evoked response (ASSR) at the binaural beat frequency in order to find a measure for temporal coding of sound in the human EEG. METHODS We stimulated each ear with a distinct tone, both differing in frequency by 40Hz, to record a binaural beat ASSR. As control, we evoked a beat ASSR in response to both tones in the same ear. We band-pass filtered the EEG at 40Hz, averaged with respect to stimulus onset and compared ASSR amplitudes and phases, extracted from a sinusoidal non-linear regression fit to a 40Hz period average. RESULTS A 40Hz binaural beat ASSR was evoked at a low mean stimulus frequency (400Hz) but became undetectable beyond 3kHz. Its amplitude was smaller than that of the acoustic beat ASSR, which was evoked at low and high frequencies. Both ASSR types had maxima at fronto-central leads and displayed a fronto-occipital phase delay of several ms. CONCLUSIONS The dependence of the 40Hz binaural beat ASSR on stimuli at low, temporally coded tone frequencies suggests that it may objectively assess temporal sound coding ability. The phase shift across the electrode array is evidence for more than one origin of the 40Hz oscillations. SIGNIFICANCE The binaural beat ASSR is an evoked response, with novel diagnostic potential, to a signal that is not present in the stimulus, but generated within the brain.
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Affiliation(s)
- D W F Schwarz
- Department of Surgery (Otolaryngology) and Brain Research Centre, University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC, Canada V6T 2B5.
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Trujillo-Barreto NJ, Aubert-Vázquez E, Valdés-Sosa PA. Bayesian model averaging in EEG/MEG imaging. Neuroimage 2004; 21:1300-19. [PMID: 15050557 DOI: 10.1016/j.neuroimage.2003.11.008] [Citation(s) in RCA: 188] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2003] [Revised: 11/03/2003] [Accepted: 11/04/2003] [Indexed: 11/25/2022] Open
Abstract
In this paper, the Bayesian Theory is used to formulate the Inverse Problem (IP) of the EEG/MEG. This formulation offers a comparison framework for the wide range of inverse methods available and allows us to address the problem of model uncertainty that arises when dealing with different solutions for a single data. In this case, each model is defined by the set of assumptions of the inverse method used, as well as by the functional dependence between the data and the Primary Current Density (PCD) inside the brain. The key point is that the Bayesian Theory not only provides for posterior estimates of the parameters of interest (the PCD) for a given model, but also gives the possibility of finding posterior expected utilities unconditional on the models assumed. In the present work, this is achieved by considering a third level of inference that has been systematically omitted by previous Bayesian formulations of the IP. This level is known as Bayesian model averaging (BMA). The new approach is illustrated in the case of considering different anatomical constraints for solving the IP of the EEG in the frequency domain. This methodology allows us to address two of the main problems that affect linear inverse solutions (LIS): (a) the existence of ghost sources and (b) the tendency to underestimate deep activity. Both simulated and real experimental data are used to demonstrate the capabilities of the BMA approach, and some of the results are compared with the solutions obtained using the popular low-resolution electromagnetic tomography (LORETA) and its anatomically constraint version (cLORETA).
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Abstract
Steady-state evoked potentials can be recorded from the human scalp in response to auditory stimuli presented at rates between 1 and 200 Hz or by periodic modulations of the amplitude and/or frequency of a continuous tone. Responses can be objectively detected using frequency-based analyses. In waking subjects, the responses are particularly prominent at rates near 40 Hz. Responses evoked by more rapidly presented stimuli are less affected by changes in arousal and can be evoked by multiple simultaneous stimuli without significant loss of amplitude. Response amplitude increases as the depth of modulation or the intensity increases. The phase delay of the response increases as the intensity or the carrier frequency decreases. Auditory steady-state responses are generated throughout the auditory nervous system, with cortical regions contributing more than brainstem generators to responses at lower modulation frequencies. These responses are useful for objectively evaluating auditory thresholds, assessing suprathreshold hearing, and monitoring the state of arousal during anesthesia.
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Affiliation(s)
- Terence W Picton
- Rotman Research Institute, Baycrest Centre for Geriatric Care, University of Toronto, Canada.
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Abstract
We used functional brain imaging with positron emission tomography (PET)-H2 15O to study a remarkable neurophysiological finding in the normal brain. Auditory stimulation at various frequencies in the gamma range elicits a steady-state scalp electroencephalographic (EEG) response that peaks in amplitude at 40 Hz, with smaller amplitudes at lower and higher stimulation frequencies. We confirmed this finding in 28 healthy subjects, each studied with monaural trains of stimuli at 12 different stimulation rates (12, 20, 30, 32, 35, 37.5, 40, 42.5, 45, 47.5, 50, and 60 Hz). There is disagreement as to whether the peak in the amplitude of the EEG response at 40 Hz corresponds simply to a superimposition of middle latency auditory evoked potentials, neuronal synchronization, or increased cortical synaptic activity at this stimulation frequency. To clarify this issue, we measured regional cerebral blood flow (rCBF) with PET-H2 15O in nine normal subjects at rest and during auditory stimulation at four different frequencies (12, 32, 40, and 47 Hz) and analyzed the results with statistical parametric mapping. The behavior of the rCBF response was similar to the steady-state EEG response, reaching a peak at 40 Hz. This finding suggests that the steady-state amplitude peak is related to increased cortical synaptic activity. Additionally, we found that, compared with other stimulation frequencies, 40 Hz selectively activated the auditory region of the pontocerebellum, a brain structure with important roles in cortical inhibition and timing.
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Abstract
The frequency-modulation following response (FMFR) is a steady-state evoked response which may be a neural correlate of frequency discrimination. Aged subjects with normal hearing have abnormal frequency discrimination for low carrier frequencies and thus it might be predicted that aged individuals would have reduced FMFR amplitudes compared to young subjects. In this study, FMFR amplitudes were measured for frequency-modulated sinusoids with a carrier frequency of 0.5 kHz (80 dB SPL). In Experiment 1, the modulation depth was held constant (80%) and the modulation rate was varied (4-38 Hz), whereas in Experiment 2 the modulation rate was held constant (38 Hz) and the modulation depth was varied (0-80%). Aged subjects had significantly larger FMFR amplitudes than young subjects for certain stimulus parameters, although individual variability was large. Such results would not be predicted given previous data regarding frequency discrimination, but are consistent with several reports of larger-than-normal amplitudes of middle latency and late responses in aged subjects.
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Affiliation(s)
- Flint A Boettcher
- Department of Otolaryngology, Head and Neck Surgery, Medical University of South Carolina, 39 Sabin Street, P.O. Box 250150, Charleston 29425, USA.
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Abstract
This paper is the second in a series of three investigating the role of cholinergic mechanisms in the auditory system by assessing the acute effects of nicotine, an acetylcholinomimetic drug, on aggregate responses within the auditory pathway. In a single-blind procedure, auditory responses were obtained from 20 normal-hearing, non-smokers (10 male) under two conditions (nicotine, placebo). The effects of nicotine on central, mesogenous responses of the auditory system (middle latency and 40-Hz responses) are described in this second paper. Results indicated that transdermal administration of nicotine to non-smokers does significantly affect the central, neural transmission of acoustic information. Na-Pa amplitude and Nb latency of the middle latency response and latency measures of the 40-Hz response were acutely altered by the presence of nicotine.
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Affiliation(s)
- A W Harkrider
- Department of Audiology and Speech Pathology, University of Tennessee, Knoxvillle, 37996, USA.
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Onofrj M, Thomas A, Iacono D, D'Andreamatteo G, Paci C. Age-related changes of evoked potentials. Neurophysiol Clin 2001; 31:83-103. [PMID: 11433676 DOI: 10.1016/s0987-7053(01)00248-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this review is to analyse the current state of our knowledge on evoked potentials (EPs) in ageing and to report some conclusions on the relation between EPs and elder age. Evoked potentials provide a measure of the function of sensory systems that change during the different stages of life. Each sensory system has its own time of maturation. The individuation of the exact period of life when brain ageing starts is difficult to define. Normally, the amplitude of EPs decreases, and their latency increases from adult to elder life. Many authors speculate that these modifications might depend on neuronal loss, changes in cell membrane, composition or senile plaques present in older patients, but there is no evidence that these changes might modify the cerebral function in healthy aged individuals. This review emphasises some incongruities present in different studies confirmed by daily neurophysiologic practice. Different techniques as event-related desynchronization (ERD), contingent negative variation (CNV) and Bereitschaftspotential, are available to study central neuronal changes in normal and pathologic ageing.
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Affiliation(s)
- M Onofrj
- Department of Oncology and Neuroscience, University G. D'Annunzio, Chieti, Italy.
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Abstract
The amplitude-modulation following response (AMFR) is a steady-state auditory response which may be an objective measure of intensity discrimination. Aged subjects with normal hearing have poorer intensity discrimination for low-frequency tones measured behaviorally, which would predict poorer AMFRs for low-frequency carriers. Experiment 1 was designed to assess age-related differences in AMFR characteristics. Response amplitudes were not significantly different among the young and aged groups for either carrier frequency (520 or 4000 Hz) or modulation depth (0--100%). Response phase did not vary systematically among groups. These results suggest that the AMFR may not be directly comparable to behavioral measures of intensity discrimination in aged subjects with normal hearing. To assess the contribution of high-frequency hearing loss on the AMFR in aged subjects, Experiment 2 compared AMFR amplitudes in aged subjects and in young subjects under the condition of high-pass masking. The amplitude of the AMFR was reduced at 520 Hz for both aged subjects and masked young subjects compared to unmasked young subjects, suggesting that reduced amplitudes in aged subjects with high-frequency hearing loss were associated with threshold elevations. Furthermore, the results suggest that the base of the cochlea contributes to the AMFR for low carrier frequencies.
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Affiliation(s)
- F A Boettcher
- Department of Otolaryngology--Head and Neck Surgery, Medical University of South Carolina, 39 Sabin Street, P.O. Box 250150, Charleston, SC 29425, USA.
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Bonhomme V, Plourde G, Meuret P, Fiset P, Backman SB. Auditory steady-state response and bispectral index for assessing level of consciousness during propofol sedation and hypnosis. Anesth Analg 2000; 91:1398-403. [PMID: 11093988 DOI: 10.1097/00000539-200012000-00018] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
UNLABELLED We assessed the effect of propofol on the auditory steady-state response (ASSR), bispectral (BIS) index, and level of consciousness in two experiments. In Experiment 1, propofol was infused in 11 subjects to obtain effect-site concentrations of 1, 2, 3, and 4 microg/mL. The ASSR and BIS index were recorded during baseline and at each concentration. The ASSR was evoked by monaural stimuli. Propofol caused a concentration-dependent decrease of the ASSR and BIS index values (r(2) = 0.76 and 0.93, respectively; P<0.0001). The prediction probability for loss of consciousness was 0.89, 0.96, and 0.94 for ASSR, BIS, and arterial blood concentration of propofol, respectively. In Experiment 2, we compared the effects of binaural versus monaural stimulus delivery on the ASSR in six subjects during awake baseline and propofol-induced unconsciousness. During baseline, the ASSR amplitude with binaural stimulation (0.47+/-0.13 microV, mean +/- SD) was significantly (P<0.002) larger than with monaural stimulation (0.35+/-0.11 microV). During unconsciousness, the amplitude was 0.09+/-0.09 microV with monaural and 0.06+/-0.04 microV with binaural stimulation (NS). The prediction probability for loss of consciousness was 0.97 (0.04 SE) for monaural and 1.00 (0.00 SE) for binaural delivery. We conclude that the ASSR and BIS index are attenuated in a concentration-dependent manner by propofol and provide a useful measure of its sedative and hypnotic effect. BIS was easier to use and slightly more sensitive. The ASSR should be recorded with binaural stimulation. The ASSR and BIS index are both useful for assessing the level of consciousness during sedation and hypnosis with propofol. However, the BIS index was simpler to use and provided a more sensitive measure of sedation. IMPLICATIONS We have compared two methods for predicting whether the amount of propofol given to a human subject is sufficient to cause unconsciousness, defined as failure to respond to a simple verbal command. The two methods studied are the auditory steady-state response, which measures the electrical response of the brain to sound, and the bispectral index, which is a number derived from the electroencephalogram. The results showed that both methods are very good predictors of the level of consciousness; however, bispectral was easier to use.
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Affiliation(s)
- V Bonhomme
- Department of Anesthesia, McGill University, Montreal, Quebec, Canada
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Ross B, Borgmann C, Draganova R, Roberts LE, Pantev C. A high-precision magnetoencephalographic study of human auditory steady-state responses to amplitude-modulated tones. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2000; 108:679-691. [PMID: 10955634 DOI: 10.1121/1.429600] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The cerebral magnetic field of the auditory steady-state response (SSR) to sinusoidal amplitude-modulated (SAM) tones was recorded in healthy humans. The waveforms of underlying cortical source activity were calculated at multiples of the modulation frequency using the method of source space projection, which improved the signal-to-noise ratio (SNR) by a factor of 2 to 4. Since the complex amplitudes of the cortical source activity were independent of the sensor position in relation to the subject's head, a comparison of the results across experimental sessions was possible. The effect of modulation frequency on the amplitude and phase of the SSR was investigated at 30 different values between 10 and 98 Hz. At modulation frequencies between 10 and 20 Hz the SNR of harmonics near 40 Hz were predominant over the fundamental SSR. Above 30 Hz the SSR showed an almost sinusoidal waveform with an amplitude maximum at 40 Hz. The amplitude decreased with increasing modulation frequency but was significantly different from the magnetoencephalographic (MEG) background activity up to 98 Hz. Phase response at the fundamental and first harmonic decreased monotonically with increasing modulation frequency. The group delay (apparent latency) showed peaks of 72 ms at 20 Hz, 48 ms at 40 Hz, and 26 ms at 80 Hz. The effects of stimulus intensity, modulation depth, and carrier frequency on amplitude and phase of the SSR were also investigated. The SSR amplitude decreased linearly when stimulus intensity or the modulation depth were decreased in logarithmic steps. SSR amplitude decreased by a factor of 3 when carrier frequency increased from 250 to 4000 Hz. From the phase characteristics, time delays were found in the range of 0 to 6 ms for stimulus intensity, modulation depth, and carrier frequency, which were maximal at low frequencies, low intensities, or maximal modulation depth.
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Affiliation(s)
- B Ross
- Center of Biomagnetism, Institute of Experimental Audiology, University of Münster, Germany.
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36
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Freeman WJ. Characterization of state transitions in spatially distributed, chaotic, nonlinear, dynamical systems in cerebral cortex. INTEGRATIVE PHYSIOLOGICAL AND BEHAVIORAL SCIENCE : THE OFFICIAL JOURNAL OF THE PAVLOVIAN SOCIETY 1994; 29:294-306. [PMID: 7811649 DOI: 10.1007/bf02691333] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The neurons of cerebral cortex are largely autonomous and generate activity that is manifested in trains of microscopic axonal action potentials. The neurons interact by sparse but numerous synaptic connections to generate macroscopic dendritic activity patterns that are observed in electroencephalographic (EEG) waves. The macroscopic patterns are constructed by the populations and they shape the output of cortical neurons in parallel arrays. Sensory cortexes receive sensory information in the form of microscopic action potentials, which induce state transitions in population dynamics. Each state transition transforms sensory information to perceptual meaning. The EEG reflects both kinds of activity. The sensory input is accessed by time ensemble averaging, whereas the perceptual output is found by spatial ensemble averaging. Spatial phase gradients in the EEG are useful for identifying EEG segments in a sequence of state transitions in response to sensory input. The rapidity and flexibility with which they take place give strong reason to postulate that the mechanism for the construction of these sequences of patterns is a dynamical system operating in a chaotic domain.
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Affiliation(s)
- W J Freeman
- Department of Molecular & Cell Biology, University of California, Berkeley 94720
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Law SK, Rohrbaugh JW, Adams CM, Eckardt MJ. Improving spatial and temporal resolution in evoked EEG responses using surface Laplacians. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1993; 88:309-22. [PMID: 7688286 DOI: 10.1016/0168-5597(93)90055-t] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Spline generated surface Laplacian temporal wave forms are presented as a method to improve both spatial and temporal resolution of evoked EEG responses. Middle latency and the N1 components of the auditory evoked response were used to compare potential-based methods with surface Laplacian methods in the time domain. Results indicate that surface Laplacians provide better estimates of underlying cortical activity than do potential wave forms. Spatial discrimination among electrode sites was markedly better with surface Laplacian than with potential wave forms. Differences in the number and latencies of peaks, and their topographic distributions, were observed for surface Laplacian, particularly during the time period encompassing the middle latency responses. Focal activities were observed in surface Laplacian wave forms and topographic maps which were in agreement with previous findings from auditory evoked response studies. Methodological issues surrounding the application of spline methods to the time domain are also discussed. Surface Laplacian methods in the time domain appear to provide an improved way for studying evoked EEG responses by increasing temporal and spatial resolution of component characteristics.
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Affiliation(s)
- S K Law
- Section of Brain Electrophysiology and Imaging, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892
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38
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Snyder AZ. Steady-state vibration evoked potentials: descriptions of technique and characterization of responses. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1992; 84:257-68. [PMID: 1375885 DOI: 10.1016/0168-5597(92)90007-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Steady-state scalp evoked potentials were recorded in response to amplitude modulated vibration applied to the fingers and palmar surface of one hand. Evoked response dependence on the frequency of amplitude modulation in the 2-40 Hz range was studied in a group of normal young adult volunteers. Response amplitude was greatest at low amplitude modulation frequencies. The greatest signal to EEG noise ratios were found at modulation frequencies near 26 Hz. At modulation frequencies near 26 Hz the steady-state response latency was found to be 58 +/- 14 msec. Inverse dipole modeling localized the steady-state evoked response generators in or near somatosensory cortex with the dipole moment orientation being predominantly in the anterior-posterior direction.
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Affiliation(s)
- A Z Snyder
- Department of Neurology and Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110
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Plourde G, Stapells DR, Picton TW. The human auditory steady-state evoked potentials. ACTA OTO-LARYNGOLOGICA. SUPPLEMENTUM 1991; 491:153-9; discussion 160. [PMID: 1814147 DOI: 10.3109/00016489109136793] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
When auditory stimuli are presented at rates near 40/s, they evoke a steady-state middle latency response. This results from the super-position of the transient responses evoked by each of the rapidly presented stimuli. The steady-state evoked potentials are most appropriately analyzed using frequency-based techniques. The response is larger for stimuli of higher intensity and of lower tonal frequency. The amplitude of the response varies with the state of arousal of the subject. Sleep results in a decrease in the amplitude to between one third and one half of the amplitude during wakefulness. The response is even further attenuated by general anesthesia. This auditory steady-state evoked potential may therefore be helpful in monitoring the state of arousal of a patient undergoing anesthesia.
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Affiliation(s)
- G Plourde
- Human Neuroscience Research Unit, University of Ottawa, Canada
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