Abstract:
:The back-projected independent components (BICs) of single-trial, auditory P300 and contingent negative variation (CNV) evoked potentials (EPs) were derived using independent component analysis (ICA) and cluster analysis. The method was tested in simulation including a study of the electric dipole equivalents of the signal sources. P300 data were obtained from healthy and Alzheimer's disease (AD) subjects. The BICs were of approximately 100 ms duration and approximated positive- and negative-going half-sinusoids. Some positively and negatively peaking BICs constituting the P300 coincided with known peaks in the averaged P300. However, there were trial-to-trial differences in their occurrences, particularly where a positive or a negative BIC could occur with the same latency in different trials, a fact which would be obscured by averaging them. These variations resulted in marked differences in the shapes of the reconstructed, artefact-free, single-trial P300s. The latencies of the BIC associated with the P3b peak differed between healthy and AD subjects (p < 0.01). More reliable evidence than that obtainable from single-trial or averaged P300s is likely to be found by studying the properties of the BICs over a number of trials. For the CNV, BICs corresponding to both the orienting and the expectancy components were found.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Jervis B,Belal S,Camilleri K,Cassar T,Bigan C,Linden DE,Michalopoulos K,Zervakis M,Besleaga M,Fabri S,Muscat Jdoi
10.1088/0967-3334/28/8/001subject
Has Abstractpub_date
2007-08-01 00:00:00pages
745-71issue
8eissn
0967-3334issn
1361-6579pii
S0967-3334(07)32374-5journal_volume
28pub_type
杂志文章abstract:UNLABELLED:The study created an 'ex vivo' model to test different algorithms for measurements of mucosal haemoglobin saturation with visible light spectrophotometry (VLS). The model allowed comparison between algorithms, but it also allowed comparison with co-oximetry using a 'gold standard' method. This has not been d...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/9/1624
更新日期:2016-09-01 00:00:00
abstract::A study of the concentrations of the common breath metabolites ammonia, acetone, isoprene, ethanol and acetaldehyde in the breath of five subjects over a period of 30 days has been carried out. Breath samples were taken and analysed in the early morning on arrival at the laboratory. The real time analyses of three con...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/24/1/308
更新日期:2003-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/1361-6579/aab659
更新日期:2018-04-26 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2018-01-31 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/abdf3d
更新日期:2021-01-22 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaaaa0
更新日期:2018-02-28 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:1998-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/019
更新日期:1993-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab21af
更新日期:2019-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/1/007
更新日期:2005-02-01 00:00:00
abstract::Using the cross-sectional images taken with the zoom-in micro-tomography technique, we measured trabecular thicknesses of femur bones in postmortem rats. Since the zoom-in micro-tomography technique is capable of high resolution imaging of a small local region inside a large subject, we were able to measure the trabec...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/5/008
更新日期:2005-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/21/1/318
更新日期:2000-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/1/040
更新日期:2004-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab5154
更新日期:2019-12-03 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/9/003
更新日期:2010-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/7/1163
更新日期:2016-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/1/006
更新日期:2007-01-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/31/5/008
更新日期:2010-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aace95
更新日期:2018-07-16 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章,随机对照试验
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更新日期:2018-04-20 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aac9a9
更新日期:2018-06-27 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/0967-3334/31/10/006
更新日期:2010-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2005-04-01 00:00:00
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doi:10.1088/1361-6579/ab924b
更新日期:2020-07-09 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/9/007
更新日期:2006-09-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2016-04-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/11/003
更新日期:2007-11-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2018-10-30 00:00:00
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更新日期:2014-08-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2019-02-26 00:00:00