Classification of EEG-Based Brain–Computer Interfaces

  • Ahmad Taher Azar
  • Valentina E. Balas
  • Teodora Olariu
Part of the Studies in Computational Intelligence book series (SCI, volume 486)


This chapter demonstrates the development of a brain computer interface (BCI) decision support system for controlling the movement of a wheelchair for neurologically disabled patients using their Electroencephalography (EEG). The subject was able to imagine his/her hand movements during EEG experiment which made EEG oscillations in the signal that could be classified by BCI. The BCI will translate the patient’s thoughts into simple wheelchair commands such as “go” and “stop”. EEG signals are recorded using 59 scalp electrodes. The acquired signals are artifacts contaminated. These artifacts were removed using blind source separation (BSS) by independent component analysis (ICA) to get artifact-free EEG signal from which certain features are extracted by applying discrete wavelet transformation (DWT). The extracted features were reduced in dimensionality using principal component analysis (PCA). The reduced features were fed to neural networks classifier yielding classification accuracy greater than 95 %.


Electroencephalography (EEG) Brain computer interface (BCI) Decision support system (DSS) Principal component analysis (PCA) Independent component analysis (ICA) Discrete wavelet transformation (DWT) Artificial neural network (ANN) Feature extraction Classification Computational Intelligence (CI) Machine learning 



The research of Valentina Emilia Balas was supported by the Bilateral Cooperation Research Project between Bulgaria-Romania (2010-2012) entitled “Electronic Health Records for the Next Generation Medical Decision Support in Romanian and Bulgarian National Healthcare Systems”, NextGenElectroMedSupport.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Ahmad Taher Azar
    • 1
  • Valentina E. Balas
    • 2
  • Teodora Olariu
    • 3
    • 4
  1. 1.Faculty of EngineeringMisr University for Science and Technology (MUST)CairoEgypt
  2. 2.Aurel Vlaicu University of AradAradRomania
  3. 3.Vasile Goldis Western University of AradAradRomania
  4. 4.Clinical Emergency County Hospital AradAradRomania

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