Cointegration of event-related potential (ERP) signals in experiments with different electromagnetic field (EMF) conditions


Due to their non-stationarity, ERP signals are difficult to study. The concept of cointegration might overcome this problem and allow for the study of the co-variability between whole ERP signals. In this context cointegration factor is defined as the ability of an ERP signal to co-vary with other ERP signals. The aim of the present study was to investigate whether the cointegration factor is dependent on different EMF conditions and gender, as well as the locations of the electrodes on the scalp. The findings revealed that women have a significantly higher cointegration factor than men, while all subjects have increased cointegration factors in the presence of EMF. The cointegration factor is location dependent, creating a distinct cluster of high coin- tegration capacity at the central and lateral electrodes of the scalp, in contrast to clusters of low cointegration capacity at the anterior and posterior electrodes There seem to be distinct similarities of the present findings with those from standard methodologies of the ERPs. In conclusion cointegration is a promising tool towards the study of functional interactions between different brain locations.

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Maganioti, A. , Chrissanthi, H. , Charalabos, P. , Andreas, R. , George, P. and Christos, C. (2010) Cointegration of event-related potential (ERP) signals in experiments with different electromagnetic field (EMF) conditions. Health, 2, 400-406. doi: 10.4236/health.2010.25060.

Conflicts of Interest

The authors declare no conflicts of interest.


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