Testing for directed influences among neural signals using partial directed coherence.

Björn Schelter; Matthias Winterhalder; Michael Eichler; Martin Peifer; Bernhard Hellwig; Brigitte Guschlbauer; Carl Hermann Lücking; Rainer Dahlhaus; Jens Timmer

doi:10.1016/j.jneumeth.2005.09.001

PubMed · 16269188

Testing for directed influences among neural signals using partial directed coherence.

Björn Schelter·Matthias Winterhalder·Michael Eichler·Martin Peifer·Bernhard Hellwig·Brigitte Guschlbauer·Carl Hermann Lücking·Rainer Dahlhaus·Jens Timmer

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Abstract

One major challenge in neuroscience is the identification of interrelations between signals reflecting neural activity. When applying multivariate time series analysis techniques to neural signals, detection of directed relationships, which can be described in terms of Granger-causality, is of particular interest. Partial directed coherence has been introduced for a frequency domain analysis of linear Granger-causality based on modeling the underlying dynamics by vector autoregressive processes. We discuss the statistical properties of estimates for partial directed coherence and propose a significance level for testing for nonzero partial directed coherence at a given frequency. The performance of this test is illustrated by means of linear and non-linear model systems and in an application to electroencephalography and electromyography data recorded from a patient suffering from essential tremor.

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Algorithms Computer Simulation Data Interpretation, Statistical Electroencephalography Electromyography Humans Linear Models Neurophysiology Nonlinear Dynamics Stochastic Processes Tremor Journal Article Research Support, Non-U.S. Gov't

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BibTeX RIS

Björn Schelter, Matthias Winterhalder, Michael Eichler, Martin Peifer, Bernhard Hellwig, Brigitte Guschlbauer, Carl Hermann Lücking, Rainer Dahlhaus, Jens Timmer. 2005-11-02. Testing for directed influences among neural signals using partial directed coherence.. https://doi.org/10.1016/j.jneumeth.2005.09.001

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