eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2022-09-29 15 3 1421 1426 10.13005/bpj/2479 45767 article Mohd. Maroof Siddiqui 1 Ruchin Jain 2 Mohd. Suhaib Kidwai 3 Mohammad Zunnun Khan 3 College of Engineering, Dhofar University, Sultanate of Oman. College of Engineering, RBCET, India. College of Engineering, Integral University, Lucknow, U.P., India Electroencephalogram (EEG) is a recording of the electrical movement of the brain from the scalp. For sleep disorder analysis the EEG test is done while the subject is sleeping. In this paper discuss about recording of brain signal (EEG) and how these signal play major role to finding in different brain diseases. EEG data can be different when subjects are asleep or when exhausted or when some sort of action takes place. When the patient is awake standard EEG test can be taken, but it may not demonstrate any unusual electrical action. During the sleep, brainwave patterns alter and may show more unusual electrical action. https://biomedpharmajournal.org/vol15no3/recording-of-eeg-signals-and-role-in-diagnosis-of-sleep-disorder/ Electroencephalogram(EEG)  Electrode Positioning System(EPS)  Montage  Polysomnography  Stages of sleep Montage