THE PROBLEM OF CHOICE OF OPTIMUM REFERENT FOR EEG REGISTRATION
Abstract
The problem to find the optimal EEG reference is the actual topic for discussion for over 60 years. In this work we studied topographical distinctions of averaged spectral amplitudes in alpha domain in 10-20%-system destinations at “closed eyes” test for 13 references: top and bottom of chin (P1, P2), tip of nose (N), top and bottom behind of neck (Sh1, Sh2), top of back (C), united front and back of neck (2Sh), united, ipsilateral and separate ears (A12, Sym, A1, A2), vertex (Cz), averaged reference (AR). Six experiments have been performed for 10 examineers with grounded and ungrounded conditions of three distant basic references P2, C, 2Sh. Pairwise estimates of topographic consistency 13 references were carried out using the proposed complex of three independent indicators and assessment criterion followed by K-means classification of reference schemes and its discriminant verification. The main results are: 1) the highly coherent topography is provided by references: А12, P1, P2, Sym; 2) A1, Sh2, A2, Sh1, AR, Cz references are characterized by considerably less coordinated and various topography that can lead to contradictory conclusions obtained by their use; 3) we didn’t find significant reasons to prefer the grounded (neutral) or ungrounded condition of basic references, that reduces the relevance of problem to search or calculate an infinitely far neutral reference. So the problem to search or mathematical construct an infinitely remote neutral reference may be no really actual.
About the Author
A. P. Kulaichev
Lomonosov Moscow State University
Russian Federation
Department of Higher Nervous Activity, School of Biology
Russian Federation
Department of Higher Nervous Activity, School of Biology
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Review
For citations:
Kulaichev A.P. THE PROBLEM OF CHOICE OF OPTIMUM REFERENT FOR EEG REGISTRATION. Vestnik Moskovskogo universiteta. Seriya 16. Biologiya. 2016;(3):38-43. (In Russ.)
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