The alpha rhythm appearing on an Electroencephalogram has which of the following characteristics?
A. It produces 20 to 30 waves per secondB. It disappears when a patient’s eyes open
C. It is replaced by slower, larger waves during REM sleep
D. It is associated with deep sleep
The Answer is B. In a totally
relaxed adult with eyes closed, the major component of the electroencephalogram
(EEG) will be a regular pattern of 8 to 12 waves per second, called the alpha
rhythm. The alpha rhythm disappears when the eyes are opened. It is most
prominent in the parieto-occipital region. In deep sleep, the alpha rhythm is
replaced by larger, slower waves called delta waves. In REM sleep, the EEG will
show fast, irregular activity.
