Abstract:
:A new method is presented for quantitative evaluation of single-sweep phase and amplitude electro-encephalogram (EEG) characteristics that is a more informative approach in comparison with conventional signal averaging. In the averaged potential, phase-locking and amplitude effects of the EEG response cannot be separated. To overcome this problem, single-trial EEG sweeps are decomposed into separate presentations of their phase relationships and amplitude characteristics. The stability of the phase-coupling to stimulus is then evaluated independently by analyzing the single-sweep phase presentations. The method has the following advantages: information about stability of the phase-locking can be used to assess event-related oscillatory activity; the method permits evaluation of the timing of event-related phase-locking; and a global assessment and comparison of the phase-locking of ensembles of single sweeps elicited in different processing conditions is possible. The method was employed to study auditory alpha and theta responses in young and middle-aged adults. The results showed that whereas amplitudes of frequency responses tended to decrease, the phase-locking increased significantly with age. The synchronization with stimulus (phase-locking) was the only parameter reliably to differentiate the brain responses of the two age groups, as well as to reveal specific age-related changes in frontal evoked alpha activity. Thus, the present approach can be used to evaluate dynamic brain processes more precisely.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Kolev V,Yordanova Jdoi
10.1007/s004220050335subject
Has Abstractpub_date
1997-03-01 00:00:00pages
229-35issue
3eissn
0340-1200issn
1432-0770journal_volume
76pub_type
杂志文章abstract::It is shown how field potentials due to neuronal membrane processes can be computed by means of a digital computer system. The essence of the method consists in evaluating a discrete expression for the field potential as a function of membrane potentials. This expression is considered as a three-dimensional convolutio...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00347640
更新日期:1980-01-01 00:00:00
abstract::We have attempted to reconcile the different patterns of distribution of interspike intervals that are found in motoneurones made to discharge by intracellular injection of constant current in reduced animal preparations and by voluntary control in human subjects. We recorded long spike trains from single motor units ...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00204057
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00198918
更新日期:1994-01-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00201423
更新日期:1995-08-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-003-0408-8
更新日期:2003-08-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-008-0251-z
更新日期:2008-09-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s004220050510
更新日期:1999-02-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00198088
更新日期:1991-01-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-014-0588-4
更新日期:2014-04-01 00:00:00
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pub_type: 杂志文章
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pub_type: 杂志文章
doi:10.1007/s00422-005-0556-0
更新日期:2005-04-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00194921
更新日期:1996-04-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-012-0544-0
更新日期:2013-04-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s004220100284
更新日期:2002-01-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-017-0719-9
更新日期:2017-08-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00198768
更新日期:1989-01-01 00:00:00
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pub_type: 杂志文章
doi:10.1007/s00422-008-0235-z
更新日期:2008-07-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00200811
更新日期:1993-01-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-015-0675-1
更新日期:2016-10-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00355690
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s004220050355
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journal_title:Biological cybernetics
pub_type: 杂志文章
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-014-0626-2
更新日期:2014-10-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00197642
更新日期:1990-01-01 00:00:00
abstract::Fitzhugh's BVP model has been used by many people. Fitzhugh has pointed out that as the stimulus is increased the model has "inverted" behaviour. It is here shown that this is due to a lack of a mechanism of inactivation, and the model is adjusted by supplying such a mechanism, to give a new model, called BPH, which, ...
journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00344278
更新日期:1982-01-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/s00422-010-0389-3
更新日期:2010-09-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
doi:10.1007/BF00344396
更新日期:1983-01-01 00:00:00
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journal_title:Biological cybernetics
pub_type: 杂志文章
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journal_title:Biological cybernetics
pub_type: 杂志文章
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更新日期:1981-01-01 00:00:00