Abstract:Pharmaco-electroencephalography (Pharmaco-EEG) studies using clinical EEG andquantitative EEG (qEEG) technologies have existed for more than 4 decades. Thisis a promising area that could improve psychotropic intervention usingneurological data. One of the objectives in our clinical practice has been tocollect EEG and quantitative EEG (qEEG) data. In the past 5 years, we haveidentified a subset of refractory cases (n = 386) found to containcommonalities of a small number of electrophysiological features in thefollowing diagnostic categories: mood, anxiety, autistic spectrum, andattention deficit disorders, Four abnormalities were noted in the majority ofmedication failure cases and these abnormalities did not appear tosignificantly align with their diagnoses. Those were the following:encephalopathy, focal slowing, beta spindles, and transient discharges. Toanalyze the relationship noted, they were tested for association with theassigned diagnoses. Fisher’s exact test and binary logistics regression foundvery little (6%) association between particular EEG/qEEG abnormalities anddiagnoses. Findings from studies of this type suggest that EEG/qEEG providesindividualized understanding of pharmacotherapy failures and has the potentialto improve medication selection.