An EEG technician can look at an electroencephalogram and tell that the subject was awake, but relaxed with eyes closed, during generation of the recording. She can tell this because the EEG recording exhibits:

Ans. A. Alpha rhythmAlpha waves are noted in the EEG in a relaxed, awake person whose eyes are closed. An alert state is indicated by beta waves. Theta and delta waves are noted during sleep. Variability in the wave forms might indicate a seizure or damage locus.