Open AccessCognitive network interactions and beta 2 coherence in processing non-target stimuli in visual oddball task
Author(s) -
Miloslav Kukleta,
Milan Brázdil,
Róbert Román,
Petr Bob,
Ivan Rektor
Publication year - 2009
Publication title -
physiological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.647
H-Index - 70
eISSN - 1802-9973
pISSN - 0862-8408
DOI - 10.33549/physiolres.931404
Subject(s) - oddball paradigm , electroencephalography , stimulus (psychology) , audiology , beta (programming language) , phase coherence , coherence (philosophical gambling strategy) , alpha (finance) , neuroscience , cognition , frequency band , pattern recognition (psychology) , psychology , event related potential , physics , computer science , medicine , developmental psychology , mathematics , cognitive psychology , statistics , computer network , construct validity , condensed matter physics , bandwidth (computing) , programming language , psychometrics
Spatiotemporal dynamics of event-related potentials (ERP)evoked by non-target stimuli in a visual oddball experiment andthe presence of coherent oscillations in beta 2 frequency band ofdecomposed EEG records from peristimulus period wereinvestigated by means of intracranial electrodes in humans.Twenty-one patients with medically intractable epilepsyparticipated in the study. The EEG signal was recorded usingplatinum electrodes implanted in several cortical and subcorticalsites. Averaged 2 s EEG records were analyzed. Task-specific EEGchanges were found in each patient, ERPs were derived from92 electrodes used (96 % of possible cases). In the majority ofanalysed cases, ERPs were composed of several distinctcomponents, and their duration was mostly longer than 1 s. Themean onset of the first ERP component was 158±132 ms afterthe stimulus (median 112 ms, minimum value 42 ms, maximumvalue 755 ms), and large variability of these onset times wasfound in all the investigated structures. Possible coherencebetween neural activities of remote brain sites was investigatedby calculating running correlations between pairs of decomposedEEG records (alpha, beta 1, beta 2 frequency bands were used,total number of correlated pairs was 662 in each frequencyband). The record pairs exhibiting highly correlated timesegments represented 23 % of all the investigated pairs in alphaband, 7 % in beta 1 band, and 59 % in beta 2 band. Ininvestigated 2 s record windows, such segments were distributedevenly, i.e. they were also found before the stimulus onset. Inconclusion, the results have implicated the idea that a lot ofrecorded ERPs was more or less by-products of chance inspreading a signal within the neuronal network, and that theirfunctional relevance was somewhat linked with the phenomenonof activity synchronization.