Inserting the Effects of Ion Channels in Mean Field Models: Application to generation of anesthetic slow waves

In this paper, effects of general anesthesia on the electroencephalogram (EEG) have been modeled with an enhanced physiological mean field theory of electrocortical activity. Enhancement is done by inserting two intrinsic ion channels (I_KNa and I _AR) in Lilly´s mean field model. In addition to excitatory and inhibitory synapses, intrinsic ion channels can generate or manipulate the brain rhythms. I_KNa and I_AR can produce slow brain rhythms (delta band frequency) in deep levels of anesthesia. We represent the activities of each mentioned ion channels by cascading a nonlinear function and a first order low pass filter. Linearized and numerical solutions of the modified model show that the power spectrum densities of simulated EEG signals are more closed to reality