<prompt> Alpha rhythm in EEG is seen inSleep with eyes closed and mind wanderingMental activityAwake with eyes openREM sleep  <response>: The EEG recordings show typical features of sleep which is broadly divided into two broadly different phases: 1. D-sleep desynchronised or dreaming sleep, also called as REM- sleep rapid eye movement sleep, active sleep, or paradoxical sleep. 2. S-sleep synchronised sleep, also called as NREM-sleep non-REM sleep, quiet sleep, or ohodox sleep. S-sleep or NREM-sleep is fuher divided into four stages, ranging from stages 1 to 4. As the person falls asleep, the person first passes through these stages of NREM-sleep. The EEG recording during the waking state shows alpha waves of 8-12 cyclessec. frequency. The onset of sleep is characterised by a disappearance of the alpha-activity. Ref: A Sho Textbook of Psychiatry, Niraj Ahuja, 7th Edition, pg. no. 133 