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Mikkelsen KB, Tabar YR, Christensen CB, Kidmose P. EEGs Vary Less Between Lab and Home Locations Than They Do Between People. Front Comput Neurosci 2021; 15:565244. [PMID: 33679356 PMCID: PMC7928278 DOI: 10.3389/fncom.2021.565244] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 01/13/2021] [Indexed: 11/24/2022] Open
Abstract
Given the rapid development of light weight EEG devices which we have witnessed the past decade, it is reasonable to ask to which extent neuroscience could now be taken outside the lab. In this study, we have designed an EEG paradigm well suited for deployment “in the wild.” The paradigm is tested in repeated recordings on 20 subjects, on eight different occasions (4 in the laboratory, 4 in the subject's own home). By calculating the inter subject, intra subject and inter location variance, we find that the inter location variation for this paradigm is considerably less than the inter subject variation. We believe the paradigm is representative of a large group of other relevant paradigms. This means that given the positive results in this study, we find that if a research paradigm would benefit from being performed in less controlled environments, we expect limited problems in doing so.
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Affiliation(s)
- Kaare B Mikkelsen
- Department of Electrical and Computer Engineering, Aarhus University, Aarhus, Denmark
| | - Yousef R Tabar
- Department of Electrical and Computer Engineering, Aarhus University, Aarhus, Denmark
| | | | - Preben Kidmose
- Department of Electrical and Computer Engineering, Aarhus University, Aarhus, Denmark
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Jamal FN, Arafat Dzulkarnain AA, Shahrudin FA, Marzuki MN. Test-Retest Reliability of Level-Specific CE-Chirp Auditory Brainstem Response in Normal-Hearing Adults. J Audiol Otol 2020; 25:14-21. [PMID: 32575950 PMCID: PMC7835438 DOI: 10.7874/jao.2020.00073] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/17/2020] [Indexed: 12/04/2022] Open
Abstract
Background and Objectives There is growing interest in the use of the Level-specific (LS) CE-Chirp® stimulus in auditory brainstem response (ABR) due to its ability to produce prominent ABR waves with robust amplitudes. There are no known studies that investigate the test-retest reliability of the ABR to the LS CE-Chirp® stimulus. The present study aims to investigate the test-retest reliability of the ABR to the LS CE-Chirp® stimulus and compare its reliability with the ABR to standard click stimulus at multiple intensity levels in normal-hearing adults. Subjects and Methods Eleven normal-hearing adults participated. The ABR test was repeated twice in the same clinical session and conducted again in another session. The ABR was acquired using both the click and LS CE-Chirp® stimuli at 4 presentation levels (80, 60, 40, and 20 dBnHL). Only the right ear was tested using the ipsilateral electrode montage. The reliability of the ABR findings (amplitudes and latencies) to the click and LS CE-Chirp® stimuli within the same clinical session and between the two clinical sessions was calculated using an intra-class correlation coefficient analysis (ICC). Results The results showed a significant correlation of the ABR findings (amplitude and latencies) to both stimuli within the same session and between the clinical sessions. The ICC values ranged from moderate to excellent. Conclusions The ABR results from both the LS CE-Chirp® and click stimuli were consistent and reliable over the two clinical sessions suggesting that both stimuli can be used for neurological diagnoses with the same reliability.
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Affiliation(s)
- Fatin Nabilah Jamal
- Department of Audiology and Speech-Language Pathology, Kulliyyah of Allied Health Sciences, International Islamic University Malaysia, Pahang, Malaysia
| | - Ahmad Aidil Arafat Dzulkarnain
- Department of Audiology and Speech-Language Pathology, Kulliyyah of Allied Health Sciences, International Islamic University Malaysia, Pahang, Malaysia
| | - Fatin Amira Shahrudin
- Department of Audiology and Speech-Language Pathology, Kulliyyah of Allied Health Sciences, International Islamic University Malaysia, Pahang, Malaysia
| | - Muhammad Nasrullah Marzuki
- Department of Audiology and Speech-Language Pathology, Kulliyyah of Allied Health Sciences, International Islamic University Malaysia, Pahang, Malaysia
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Aerial low-frequency hearing in captive and free-ranging harbour seals (Phoca vitulina) measured using auditory brainstem responses. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2016; 202:859-868. [PMID: 27796483 PMCID: PMC5099358 DOI: 10.1007/s00359-016-1126-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 11/11/2022]
Abstract
The hearing sensitivity of 18 free-ranging and 10 captive harbour seals (Phoca vitulina) to aerial sounds was measured in the presence of typical environmental noise through auditory brainstem response measurements. A focus was put on the comparative hearing sensitivity at low frequencies. Low- and mid-frequency thresholds appeared to be elevated in both captive and free-ranging seals, but this is likely due to masking effects and limitations of the methodology used. The data also showed individual variability in hearing sensitivity with probable age-related hearing loss found in two old harbour seals. These results suggest that the acoustic sensitivity of free-ranging animals was not negatively affected by the soundscape they experienced in the wild.
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Tan XD, Peng X, Zhan CA, Wang T. Comparison of Auditory Middle-Latency Responses From Two Deconvolution Methods at 40 Hz. IEEE Trans Biomed Eng 2015; 63:1157-66. [PMID: 26441440 DOI: 10.1109/tbme.2015.2485273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
GOAL Auditory middle-latency responses (MLRs) are reported to be particularly susceptible to stimulation rate. Deconvolution methods are necessary to unwrap the overlapping responses at a high rate under the linear superposition assumption. This study aims to investigate and compare the MLR characteristics at high and conventional stimulation rates. METHODS The characteristics were examined in healthy adults by using two closely related deconvolution paradigms, namely continuous-loop averaging deconvolution and multirate steady-state averaging deconvolution at a mean rate of 40 Hz, and a conventional low rate of 5 Hz. RESULTS The morphology and stability of the MLRs can benefit from a high-rate stimulation. It appears that stimulation sequencing strategies of deconvolution methods exerted divergent rate effects on MLR characteristics, which might be associated with different adaptation mechanisms. CONCLUSION MLRs obtained by two deconvolution methods and the conventional reference feature differently from one another. SIGNIFICANCE These findings have critical implications in our current understanding of the rate effects on MLR characteristics which may inspire further studies to explore the characteristics of evoked responses at high rates and deconvolution paradigms.
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Matsushita S, Oda S, Otaki K, Nakane M, Kawamae K. Change in auditory evoked potential index and bispectral index during induction of anesthesia with anesthetic drugs. J Clin Monit Comput 2014; 29:621-6. [PMID: 25427598 PMCID: PMC4565886 DOI: 10.1007/s10877-014-9643-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 11/18/2014] [Indexed: 11/23/2022]
Abstract
The aim of this study was to evaluate the efficacy of the auditory evoked potential (AEP) index (aepEX) as an assessment tool for hypnosis during induction of various anesthetic drugs, and to compare its performance to that of the bispectral index (BIS). A total of 45 cases were divided into three groups based on the drugs used for anesthesia. Before anesthetic induction, BIS and AEP monitors were initiated. Anesthesia was induced through intravenous injection (IV) as follows: MP (n = 15) group, midazolam (0.1 mg/kg IV); TP (n = 15) group, thiopental (4 mg/kg IV); and KP (n = 15) group, ketamine (2 mg/kg IV). After loss of response (LOR), an infusion of 3 μg/ml propofol via a target-controlled infusion was initiated in all groups. AepEX and BIS were measured in the waking state (baseline) and at LOR (1 min after LOR), pre-intubation (1 min after previous intubation) and post-intubation (1 min after tracheal intubation finished). The value of aepEX significantly decreased in all groups with LOR and that of BIS also decreased except of KP group. No significant difference were observed in BIS values between baseline and LOR in the KS group. The aepEX might be more useful than BIS for hypnosis monitoring during anesthetic induction, particularly when drugs such as ketamine are used.
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Affiliation(s)
- Sachiko Matsushita
- Department of Anesthesiology, Faculty of Medicine, Yamagata University, Iida-nishi 2-2-2, Yamagata-shi, Yamagata, 990-2323, Japan.
| | - Shinya Oda
- Department of Anesthesiology, Faculty of Medicine, Yamagata University, Iida-nishi 2-2-2, Yamagata-shi, Yamagata, 990-2323, Japan
| | - Kei Otaki
- Department of Anesthesiology, Faculty of Medicine, Yamagata University, Iida-nishi 2-2-2, Yamagata-shi, Yamagata, 990-2323, Japan
| | - Masaki Nakane
- Department of Anesthesiology, Faculty of Medicine, Yamagata University, Iida-nishi 2-2-2, Yamagata-shi, Yamagata, 990-2323, Japan
| | - Kaneyuki Kawamae
- Department of Anesthesiology, Faculty of Medicine, Yamagata University, Iida-nishi 2-2-2, Yamagata-shi, Yamagata, 990-2323, Japan
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Dzulkarnain AAA, Buyong AS, Sulaiman NH. Intra-subject variability in the auditory brainstem response using a vertical montage recording. SPEECH LANGUAGE AND HEARING 2014. [DOI: 10.1179/2050572814y.0000000035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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de Araújo Lucas Rodrigues P, Pereira Lauris JR, Schochat E. Efferent inhibitory effect observed in otoacoustic emissions and auditory brainstem response in the neonatal population. Folia Phoniatr Logop 2014; 65:208-13. [PMID: 24503960 DOI: 10.1159/000356474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To characterize the inhibitory effect (IE) in the otoacoustic emission (OAE) and auditory brainstem response (ABR) in newborns at high and low risk for hearing loss. DESIGN Cross-sectional study. PATIENTS AND METHODS Seventy-nine newborns at low risk for hearing loss and 46 at high risk underwent transient evoked OAE (TEOAE), distortion product OAE (DPOAE) and ABR testing with or without the presence of contralateral white noise presented at a level of 60 dB SPL. RESULTS For both low- and high-risk newborns, there were no significant differences in IE between the left and right ears. There was a statistically significant difference in the right-ear IE between the low- and high-risk group for DPOAE and ABR testing. There was also greater agreement of the efferent system evaluation outcomes between TEOAE and ABR. CONCLUSIONS ABR testing detected IE in a greater number of newborns in the low-risk, as compared to the high-risk group.
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P1 amplitude across replicates: does measurement method make a difference? J Clin Neurophysiol 2013; 30:287-90. [PMID: 23733094 DOI: 10.1097/wnp.0b013e31828736a0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE Most cortical auditory evoked potentials instruments provide a "default" peak-to-baseline (P-B) amplitude and a means for obtaining a peak-to-trough (P-T) measure. This study investigated the sensitivity of these two measures in assessing the effects of repeated runs on the P1 component of the electrophysiological response. METHODS Cortical auditory evoked potentials were recorded on 30 normal hearing young adults. Three stimuli were used: an 80-millisecond synthetic /da/ and a 1 kHz tone burst of 40- and 80-millisecond durations. Stimuli were presented at 60 dB normal hearing level in a counterbalanced order. Three serial replicates were obtained for each stimulus. P1 amplitude and latency were measured. RESULTS The P-T amplitudes diminished significantly (P < 0.01) from replicate 1 to replicate 3 for each of the three stimulus types, but P-B amplitudes did not. P1 latency findings were consistent with effects shown by diminished P-T amplitude data in which latency increased significantly (P = 0.024) from replicate 1 to replicate 3 for one stimulus (40-millisecond tone). CONCLUSIONS The P-T amplitude measurement method identified significant decrements in amplitude because repeated runs were obtained, whereas the P-B method did not. These findings suggest that a P-T method is more sensitive to some P1 electrophysiological activity than is a P-B measure.
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Atcherson SR, Gould HJ, Pousson MA, Prout TM. Long-term stability of N1 sources using low-resolution electromagnetic tomography. Brain Topogr 2007; 19:11-20. [PMID: 16977489 DOI: 10.1007/s10548-006-0008-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The purpose of this study was to investigate the long-term stability of auditory N1 sources using low-resolution electromagnetic tomography (LORETA). Data collected from 72 electrodes in ten young adult female participants were analyzed. For each participant, N1 peak amplitude and latency values at Cz (referred to M2) were compared for right, left, and bilateral stimulation across three separate recording sessions. Further, sources calculated by LORETA were analyzed in three regions of interest: right temporal, left temporal, and frontal. Peak amplitude and latency measurements were stable across session and ear of stimulation. Three-way RM-ANOVAs revealed relatively stable source amplitudes and stable three-dimensional locations of the sources in each region of interest with shifts of up to 2 cm around the mean locations. The 2 cm variability may be attributable both to normal hemispheric asymmetries and electrode placement variability. These results suggest that N1 scalp activity and its underlying sources are stable.
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Affiliation(s)
- Samuel R Atcherson
- School of Audiology and Speech-Language Pathology, Auditory Electrophysiology Laboratory, The University of Memphis, Memphis, TN, USA.
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Sörös P, Michael N, Tollkötter M, Pfleiderer B. The neurochemical basis of human cortical auditory processing: combining proton magnetic resonance spectroscopy and magnetoencephalography. BMC Biol 2006; 4:25. [PMID: 16884545 PMCID: PMC1553472 DOI: 10.1186/1741-7007-4-25] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Accepted: 08/03/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A combination of magnetoencephalography and proton magnetic resonance spectroscopy was used to correlate the electrophysiology of rapid auditory processing and the neurochemistry of the auditory cortex in 15 healthy adults. To assess rapid auditory processing in the left auditory cortex, the amplitude and decrement of the N1m peak, the major component of the late auditory evoked response, were measured during rapidly successive presentation of acoustic stimuli. We tested the hypothesis that: (i) the amplitude of the N1m response and (ii) its decrement during rapid stimulation are associated with the cortical neurochemistry as determined by proton magnetic resonance spectroscopy. RESULTS Our results demonstrated a significant association between the concentrations of N-acetylaspartate, a marker of neuronal integrity, and the amplitudes of individual N1m responses. In addition, the concentrations of choline-containing compounds, representing the functional integrity of membranes, were significantly associated with N1m amplitudes. No significant association was found between the concentrations of the glutamate/glutamine pool and the amplitudes of the first N1m. No significant associations were seen between the decrement of the N1m (the relative amplitude of the second N1m peak) and the concentrations of N-acetylaspartate, choline-containing compounds, or the glutamate/glutamine pool. However, there was a trend for higher glutamate/glutamine concentrations in individuals with higher relative N1m amplitude. CONCLUSION These results suggest that neuronal and membrane functions are important for rapid auditory processing. This investigation provides a first link between the electrophysiology, as recorded by magnetoencephalography, and the neurochemistry, as assessed by proton magnetic resonance spectroscopy, of the auditory cortex.
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Affiliation(s)
- Peter Sörös
- Department of Imaging Research, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Nikolaus Michael
- Department of Psychiatry, University Hospital Münster, Münster, Germany
| | - Melanie Tollkötter
- Department of Clinical Radiology, University Hospital Münster, Münster, Germany
| | - Bettina Pfleiderer
- Department of Clinical Radiology, University Hospital Münster, Münster, Germany
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Lauter JL, Lynch O, Wood SB, Schoeffler L. Physiological and behavioral effects of an antivertigo antihistamine in adults. Percept Mot Skills 1999; 88:707-32. [PMID: 10407877 DOI: 10.2466/pms.1999.88.3.707] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
12 neurologically normal adults were tested before and after administration of meclizine, an over-the-counter medication for motion sickness. A battery of four tests was used: (1) distortion-product otoacoustic emissions, (2) the Repeated Evoked Potentials version of the Auditory Brainstem Response, (3) quantitative electroencephalography measured over the left and right sides of the auditory cortex, and (4) a hand-eye coordination task. The battery required approximately 1.5 hr. to complete. Each subject was tested with the battery in each of eight longitudinal sessions: three times on a control day (9 am, 1 pm, 3 pm--no medication); the same times on a second day one week later (medication at approximately 11:30 am), and 24- and 48-hr. check-up sessions following the medication day. Analysis indicated changes in all components, with details suggesting the site(s) of action of this type of antihistamine. The cross-section of the auditory system yielded by this battery makes it possible to observe effects at the periphery, in the brainstem, and in the cortex, including evidence linking otoacoustic emissions with central auditory physiology. Implications range from cautions regarding the use of antihistamines to physiological support for employing such medications to enhance patients' response to vestibular rehabilitation as well as to improve performance in learning-disordered children.
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Affiliation(s)
- J L Lauter
- Department of Communication Sciences and Disorders, University of Oklahoma Health Sciences Center, Oklahoma City 73190, USA
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Lauter JL, Oyler RF, Lord-Maes J. Amplitude stability of auditory brainstem responses in two groups of children compared with adults. BRITISH JOURNAL OF AUDIOLOGY 1993; 27:263-71. [PMID: 8312849 DOI: 10.3109/03005369309076703] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A recent report indicated that patterns of systematic variation may be observed in ABR peak latency of children from two age groups, and that comparisons of the children's latency data with similar findings in adults suggest new evidence for developmental changes in the human central auditory nervous system persisting as late as 12 years of age. The current report examines the stability of auditory brainstem response (ABR) peak amplitude for the same three groups of subjects, including: (1) across-age comparisons of absolute amplitude, between-subjects group stability, and within-subjects group stability; (2) documentation of individual differences in amplitude stability by peak and by ear; and (3) demonstration of the degree of replicability of amplitude stability patterns. Results indicate that the same observations are to made for ABR amplitude as for latency; that is, systematic patterns of stability at all three ages, with details that provide additional evidence for developmental changes in brainstem-mediated auditory electrophysiological response continuing into the second decade of life.
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Affiliation(s)
- J L Lauter
- Institute for Neurogenic Communication Disorders, University of Arizona, Tucson 85721
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Lauter JL, Wood SB. Auditory-brainstem synchronicity in dyslexia measured using the REPs/ABR protocol. Ann N Y Acad Sci 1993; 682:377-9. [PMID: 8323140 DOI: 10.1111/j.1749-6632.1993.tb22998.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- J L Lauter
- Department of Communication Disorders, University of Oklahoma Health Sciences Center, Oklahoma City 73190
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Lauter JL, Oyler RF. Latency stability of auditory brainstem responses in children aged 10-12 years compared with younger children and adults. BRITISH JOURNAL OF AUDIOLOGY 1992; 26:245-53. [PMID: 1446188 DOI: 10.3109/03005369209076643] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Previous articles have reported the results of using standard clinical procedures in our laboratory for testing auditory brainstem responses (ABR) in a repeated-measures design, in order to quantify ABR latency and amplitude stability in normal young adults. In a subsequent paper, these findings were extended to include the results of similar procedures in a group of seven children ranging in age from 5 to 7 years. The current experiment involves repeated-measures ABRs in a group of nine children ranging in age from 10 to 12 years. Results indicate that while these older children show the expected similarities with adults in terms of ABR peak latencies, their latency stability values are in some cases significantly lower than adults. At the same time, ABR stabilities measured in the older children show some differences compared to data from the younger children studied previously. For all groups, the same types of patterns are observed: (1) significant differences contrasting the degree of between-subject v. within-subject latency stability; (2) clear individual differences characterizing subjects; (3) within-subject distinctions according to ear of stimulation; and (4) instances of good replicability of the 'latency-stability profiles' calculated for one set of repeated waveforms v. a second set collected later in testing.
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Affiliation(s)
- J L Lauter
- Institute for Neurogenic Communication Disorders, University of Arizona, Tucson 85721
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Lauter JL. Processing asymmetries for complex sounds: comparisons between behavioral ear advantages and electrophysiological asymmetries based on quantitative electroencephalography. Brain Cogn 1992; 19:1-20. [PMID: 1605947 DOI: 10.1016/0278-2626(92)90035-k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This experiment extends our earlier work on individual differences in ear advantages for complex sounds (Lauter 1982, 1983, 1984) to examine the results of combined behavioral and qEEG testing in the same subjects. Results include: (1) between-subject differences in absolute values together with between-subject agreements in terms of relative values, observed both for ear advantages (EAs) and hemisphere advantages (HAs); (2) within-subject agreement between behavioral (EAs) and physiological (HAs) measures of asymmetries; and (3) preliminary findings related to the interpretation of qEEG asymmetry data, such as the influence of hand movements on auditory-cortex qEEG recordings, and persistence of activation effects in which asymmetries evoked during a stimulation condition may be reflected in resting asymmetries observed during a subsequent control condition.
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Affiliation(s)
- J L Lauter
- Institute for Neurogenic Communication Disorders, University of Arizona
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