simulation of spatio-temporal visual evoked eeg's
The relationship between scalp potentials evoked by visual stimulation and neuronal functioning is examined. A neuronal population model for the electrogenesis of the evoked surface potentials is developed which relies on the hypothesis that the surface potentials may arise from a combination of excitatory post synaptic potentials (EPSPs) and inhibitory post synaptic potentials (IPSPs) firing both at different depths and at different latencies. The model can be used to determine the location (depth and radial coordinates) of the sources and the approximate size of the neuronal population giving rise to the potential. The spatio-temporal potential fields evoked by visual stimulation and monitored by an array of scalp electrodes over the occipital cortex are then discussed along with our method for displaying these fields via contour maps. The experimental data are then computer simulated via discrete spatially disparate sources whose waveform parameters are related to the underlying neuronal activity. The waveform of each of the neuronal population sources is determined and the various parameters of the waveform are related to the major characteristics of the spatio-temporal visual evoked potential fields as well as to specific features of the neuronal population. The latter includes the sequence of neuronal excitation, the amplitude of excitatory current, the depth of the neuronal population, and the period of activity of the EPSP and IPSP.
simulation eeg modeling displays eeg simulation eeg displays visual evoked responses neuronal model