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
1  Computer Assisted Physics Group, University of Zürich, Switzerland
G. B. Schmid
2  General Psychiatry, Cantonal Psychiatric Clinic, Rheinau, Switzerland
H. H. Stassen
3  Psychiatric University Hospital, Research Dept., Zürich, Switzerland
› Author Affiliations
Further Information

Publication History

Publication Date:
07 February 2018 (online)


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.