Abstract: A method for determining effects of a drug on a central nervous system (CNS) of a subject, comprises the steps of: detecting and locating three-dimensional (3-D) brain source regions of first brain waves of the subject using a functional neuroimaging system, the first brain waves being indicative of a CNS disorder and comparing the first brain waves at each of the regions to control data corresponding to brain wave activity of corresponding brain regions in the absence of the CNS disorder. After these steps the drug is administered to the subject and second brain waves of the subject are measured from the brain source regions and compared to one of the first brain waves and the control data. The drug's effectiveness in regard to the CNS disorder is then determined based on the comparison.