About an year ago I had to take an EEG, because I had terrible cluster headaches that last only few seconds to minutes. While taking the test, the technician was constantly telling me to stay awake even while I was wide awake.

Later I saw that my EEG reads prominent long wave-lengths that resemble delta waves usually found while in deep sleep. I'm sure I didn't fall asleep at all during the test. Other than that, alpha and beta were very weak.

The doctor and neurologist didn't say much about that. But I have seen several EEGs, not as many as they have. All I know from them is that they didn't find anything related to a cluster headache from that EEG.

What does that really mean to have prominent delta waves while wide awake..