Deterministic brain oscillations in the magnetoencephalogram

Determinism is a special property of some systems and is defined by its sta te-space behavior in which the trajectories in time never intersect. Whethe r or not determinism exists in brain activities is a question that may be r esolved by analysis of the dynamical properties of the electroencephalogram (EEG) or magnetoencephalogram (MEG). We will show that even though there a re strong nonstationarities in most brain behaviors, small epochs of determ inistic dynamics can still be observed. We will also show that the local Ly apunov exponents are measures that can demonstrate smooth transitions into these deterministic states.