A new approach to classification of upper limb and wrist movements using EEG signals

Abstract

Brain computer interface (BCI) systems have ushered a new era of neural engineering research. At the core of BCIi research is development of data acquisition, filtration and classification techniques that can accurately decode the brain activity that occurs while performing a motor task. In this study, we investigate the classification accuracy of lda, QDA, Naïve Bayes, quadratic SVM and RBF SVM classifiers for classifying the flexion/extension of forearm and wrist. Moreover, hjorth parameters and PSD are employed as feature extraction techniques to derive four different feature vectors that are later used to train our classifiers. At the culmination of this study, it is shown that QDA classifier trained with PSD feature vector has the highest classification accuracy at 77.37% followed by q-SVM trained with activity feature vector at 73.97%. Apart from enhancing accuracy of classifying the four fundamental upper limb movements, this study will eventually contribute towards developing better controllers for neuro-prosthetic devices. The study has been performed experimentally with Emotiv headsets equipped with 14 electrodes to acquire EEG data from two human test subjects in synchronous mode. Classification and data analysis has been performed offline however in future the study will be extended to an online BCI system.