
M. Trifonov, V. Rozhkov
4. Conclusions and Future Work
The results of this study allow us to make a preliminary conclusion that one-dimensional pdf’s of EEG relative
displace ments can be used for understanding of the real EEG dynamics in various functional states and different
subjects. To a first approximation, in each case the empirically derived pdf are fitted quite well by the single
hyper gamma distribution. It means that only two parameters (sample mean of EEG relative displacements and
coefficient of variation) may be taken into account. Both these parameters exhibit subject’s individuality. The
first one reveals age and state dependence while the second one stays rather stable for a given subject over long
period of time except sleep stages. It is interesting to note that age-related dependence of E[ΔY1] looks like as
age-related dependence of the total brain white matter volume given in [9]. In addition the non-linear age effect
on E[ΔY1] is consistent with the suggestion that during late childhood period there is a shift of topological or-
ganization of brain white matter toward a more randomized configuration [10].
In our future research we are going to analyze much more EEG records to investigate in details the age and
time-specific dependence of the parameters mentioned above. The next interesting aspect of our future work is
the improvement of the fitting quality of the empirically derived pdf of EEG relative displacements by using
distribution that consists of a mixture of hyper gamma distribution.
Acknowledgements
The authors would like to express their sincere thanks to Prof. M. N. Tsitseroshin, Dr. E. A. Panasevich, and Dr.
S. S. Bekshaev for providing EEG data.
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