title: Filtering multifocal VEP signals using Prony's method.
abstract: BACKGROUND
  This paper describes use of Prony's method as a filter applied to multifocal visual-evoked-potential (mfVEP) signals. Prony's method can be viewed as an extension of Fourier analysis that allows a signal to be decomposed into a linear combination of functions with different amplitudes, damping factors, frequencies and phase angles.
  
  
  METHODS
  By selecting Prony method parameters, a frequency filter has been developed which improves signal-to-noise ratio (SNR). Three different criteria were applied to data recorded from control subjects to produce three separate datasets: unfiltered raw data, data filtered using the traditional method (fast Fourier transform: FFT), and data filtered using Prony's method.
  
  
  RESULTS
  Filtering using Prony's method improved the signals' original SNR by 44.52%, while the FFT filter improved the SNR by 33.56%. The extent to which signal can be separated from noise was analysed using receiver-operating-characteristic (ROC) curves. The area under the curve (AUC) was greater in the signals filtered using Prony's method than in the original signals or in those filtered using the FFT.
  
  
  CONCLUSIONS
  filtering using Prony's method improves the quality of mfVEP signal pre-processing when compared with the original signals, or with those filtered using the FFT.
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Fernández
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain. Electronic address: luis.desantiago@uah.es.
authors.forename: L
authors.initials: L
authors.lastname: de Santiago
authors.affiliation: Department of Surgery, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Blanco
authors.affiliation: Department of Surgery, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Pérez-Rico
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Rodríguez-Ascariz
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Barea
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Miguel-Jiménez
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: J R
authors.initials: JR
authors.lastname: García-Luque
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Ortiz del Castillo
authors.affiliation: Department of Psychiatry, University Hospital of Guadalajara, Guadalajara, Spain.
authors.forename: E M
authors.initials: EM
authors.lastname: Sánchez-Morla
authors.affiliation: Department of Electronics, University of Alcalá, Plaza de S. Diego, s/n, 28801 Alcalá de Henares, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Boquete
mesh_terms: D000328:Adult; D004569:Electroencephalography / Q000295:instrumentation / Q000379:methods*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D012815:Signal Processing, Computer-Assisted
keywords: Biosignal processing; Prony’s method; ROC curve; Signal-to-noise ratio; mfVEP