Aims and Objective: To assess and compare QEEG findings (mean absolute power values of theta wave) between Patients on Methylphenidate and Drug naive ADHD patients. Methodology: A total no of 78 participants included in the study 26 in each group (Drug naïve ADHD children, ADHD children taking methylphenidate more than 3 months and healthy controls). Participated in the study after taking informed consent, scalp EEG was done and then fourier transformation was done by using BESS (brain electro scan software) of the Axxonet System (India).Statistical analysis was done using SPSS software. Results: In QEEG, mean absolute power value of theta wave found increased in frontal area electrodes in ADHD children comparing to ADHD participant who were on methylphenidate treatment more than 3 months, which was statistically significant. Conclusion: Use of Quantitative EEG can allow researchers to more precisely understand the brain origins and increase understanding of Pathophysiology
