Feedback effect analysis by comparison of discrimination capability of On-line and Off-line experimental procedures based on LDA

Abstract

This paper analyses the user’s feedback influence in the mental task discrimination capability through the comparison of results obtained from Off-line and On-line Brain Computer Interface experimental procedures. Experiments performed under these two paradigms were carried out by five male volunteers. In order to develop a wearable BCI device only two electrodes in C3 and C4 zones have been used for electroencephalographic signal acquisition. These procedures apply seven different types of preprocessing windows and Linear Discrimination Analysis technique to reduce the dimension of the feature space before the quantification of the discrimination capability between the proposed mental activities. The discrimination capability is quantified through statistical analysis, based on bilateral contrast test, between the population of the LDA transformed feature vectors.