Application of dimension estimation and surrogate data to the time evolution of EEG topographic variables.
Dimensional complexity (estimated correlation dimension) was measured for two topographic EEG time series: (a) the time evolution of global field power (GFP) and (b) the time evolution of sequential dissimilarity (SQD) for resting, eyes-closed and eyes-open data. Eyes-closed GFP and eyes-closed/open SQD all had an element of nonlinearity in their dynamics as evidenced by increased dimensional complexity associated with the phase-angle randomization, Gaussian surrogate-data procedure. However, none of the three gave any evidence of being deterministic chaotic processes. Eyes-open GFP dimensional complexity could not be distinguished from a linear-stochastic process.
Pritchard
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WS
Psychophysiology Laboratory Bowman Gray Technical Center, R.J. Reynolds Tobacco Company, Winston-Salem, NC 27102, USA.
Krieble
K K
KK
Duke
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DW
D000328:Adult; D003627:Data Interpretation, Statistical; D004569:Electroencephalography / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D017711:Nonlinear Dynamics; D012016:Reference Values; D013997:Time Factors