  The flicker-noise spectroscopy (FNS) approach is used to determine the
dynamic characteristics of neuromagnetic responses by analyzing the
magnetoencephalographic (MEG) signals recorded as the response of a group of
control human subjects and a patient with photosensitive epilepsy (PSE) to
equiluminant flickering stimuli of different color combinations. Parameters
characterizing the analyzed stochastic biomedical signals for different
frequency bands are identified. It is shown that the classification of the
parameters of analyzed MEG responses with respect to different frequency bands
makes it possible to separate the contribution of the chaotic component from
the overall complex dynamics of the signals. It is demonstrated that the
chaotic component can be adequately described by the anomalous diffusion
approximation in the case of control subjects. On the other hand, the chaotic
component for the patient is characterized by a large number of high-frequency
resonances. This implies that healthy organisms can suppress the perturbations
brought about by the flickering stimuli and reorganize themselves. The
organisms affected by photosensitive epilepsy no longer have this ability. This
result also gives a way to simulate the separate stages of the brain cortex
activity in vivo. The examples illustrating the use of the "FNS device" for
identifying even the slightest individual differences in the activity of human
brains using their responses to external standard stimuli show a unique
possibility to develop the "individual medicine" of the future.
