Systems and methods are provided for measuring electrical activity within a brain of a patient. An electrode array is configured to take measurements of electrical potential as raw electroencephalographic (EEG) data. A data processing component includes a spectral decomposition component configured to divide the raw EEG data into a plurality of frequency intervals, within a total range of frequencies and an inverse solution component configured to transform the raw EEG data associated with each frequency interval into a spatial mapping of electrical activity as to provide a set of parameters, with each parameter representing an average electrical activity at an associated location within the brain over an epoch of interest.