Reduction of ocular artefacts in source current density brain mappings by ARX2 filtering

G. C. Filligoi, L. Capitanio, F. Babiloni, L. Fattorini, A. Urbano, S. Cerutti

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Sweep by sweep analysis of event-related potentials (ERP) of the human scalp represents a reliable tool for both the diagnosis of neurologic diseases and the study of the central nervous system during cognitive tasks. The off-line procedure based on stochastic parametric identification and filtering herewith described, allows an accurate analysis of single-sweep ERP and a drastic reduction of ocular artefacts variously propagating through the skull. Moreover, the spatial distribution of the recorded ERP in bidimensional form was enhanced by using the Laplacian operator in order to get an estimate of the source current density (SCD) flow from the skull into the scalp. Complete single-trial signals were filtered according to an autoregressive model of signal generation with 2 exogenous inputs (ARX2). The ARX2 procedure models the recorded signal as the sum of three signals: (a) the background EEG activity, modelled as an autoregressive process driven by a white noise; (b) a filtered version of a reference signal carrying the average information contained in each sweep; (c) a signal due to the ocular artefact propagation. The evaluation of the effect of artefact suppression on those channels close to the eyes was compared with standard ordinary least squares method (OLS) based on a linear model of the influence of EOG on ERP. Finally, the better results obtainable through ARX filtering on sweep-by-sweep brain mappings are also presented.

Original languageEnglish
Pages (from-to)282-290
Number of pages9
JournalMedical Engineering and Physics
Volume17
Issue number4
Publication statusPublished - Jun 1995

Fingerprint

Brain mapping
Brain Mapping
Evoked Potentials
Artifacts
Current density
Scalp
Skull
Neurology
White noise
Electrooculography
Electroencephalography
Spatial distribution
Nervous System Diseases
Least-Squares Analysis
Linear Models
Central Nervous System

Keywords

  • autoregressive model with exogenous inputs
  • Event related potentials
  • ordinary least square method
  • scalp current density

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biophysics
  • Orthopedics and Sports Medicine
  • Psychology(all)

Cite this

Filligoi, G. C., Capitanio, L., Babiloni, F., Fattorini, L., Urbano, A., & Cerutti, S. (1995). Reduction of ocular artefacts in source current density brain mappings by ARX2 filtering. Medical Engineering and Physics, 17(4), 282-290.

Reduction of ocular artefacts in source current density brain mappings by ARX2 filtering. / Filligoi, G. C.; Capitanio, L.; Babiloni, F.; Fattorini, L.; Urbano, A.; Cerutti, S.

In: Medical Engineering and Physics, Vol. 17, No. 4, 06.1995, p. 282-290.

Research output: Contribution to journalArticle

Filligoi, GC, Capitanio, L, Babiloni, F, Fattorini, L, Urbano, A & Cerutti, S 1995, 'Reduction of ocular artefacts in source current density brain mappings by ARX2 filtering', Medical Engineering and Physics, vol. 17, no. 4, pp. 282-290.
Filligoi GC, Capitanio L, Babiloni F, Fattorini L, Urbano A, Cerutti S. Reduction of ocular artefacts in source current density brain mappings by ARX2 filtering. Medical Engineering and Physics. 1995 Jun;17(4):282-290.
Filligoi, G. C. ; Capitanio, L. ; Babiloni, F. ; Fattorini, L. ; Urbano, A. ; Cerutti, S. / Reduction of ocular artefacts in source current density brain mappings by ARX2 filtering. In: Medical Engineering and Physics. 1995 ; Vol. 17, No. 4. pp. 282-290.
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