Intraindividual Specificity and Stability of Human EEG: Comparing a Linear vs a Nonlinear Approach

R. M. Dünki; G. B. Schmid; H. H. Stassen

doi:10.1055/s-0038-1634249

Methods of Information in Medicine, Table of Contents

Methods Inf Med 2000; 39(01): 78-82
DOI: 10.1055/s-0038-1634249

Original Article

Schattauer GmbH

Intraindividual Specificity and Stability of Human EEG: Comparing a Linear vs a Nonlinear Approach

R. M. Dünki

¹Computer Assisted Physics Group, University of Zürich, Switzerland

,

G. B. Schmid

²General Psychiatry, Cantonal Psychiatric Clinic, Rheinau, Switzerland

,

H. H. Stassen

³Psychiatric University Hospital, Research Dept., Zürich, Switzerland

› Author Affiliations

Abstract

Abstract:

We have applied the so-called “unfolding dimension approach’’ to reanalyze an earlier longitudinal EEG study. Both linear and nonlinear approaches show that the EEG comprises a static, person-specific part upon which nonstatic and state-specific parts are superimposed. The intraindivi-dual specificity and stability of the genetic part are similar between methods. This is assessed by comparing the outcome of a person to his own outcomes at later times (14 days and 5 years later). The nonlinear method revealed a median correlation coefficient = 0.55, whereas advanced linear methods showed a median = 0.84. An apparent effect for the 5-year interval was detected with the nonlinear method and is discussed in terms of the different assumptions of the two approaches concerning EEG signal generation.

Keywords:

Dimension Analysis - Similarity Approach - EEG Stability - Power Spectrum

Full Text

References

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