Question

Which rhythm is the principal component of the EEG that indicates the alertness of the brain?

• A. Theta rhythm
• B. Gamma rhythm
• C. Beta rhythm
• D. Alpha rhythm

Hint:

\textbf{Tip:} Alpha rhythms are strongest when you are awake, relaxed, and not actively processing information—like when your eyes are closed but you are not asleep.

Answer 1

The Correct Option is D

The Alpha rhythm is one of the main components of the electroencephalogram (EEG) and is predominantly observed when a person is awake but relaxed with closed eyes.
It is typically seen in the posterior regions of the brain, particularly the occipital lobe.
Alpha waves range from 8 to 13 Hz in frequency.
These rhythms decrease or disappear with mental exertion or when the eyes are opened, indicating a shift to alert cognitive processing.
Therefore, alpha rhythms are often used to assess brain alertness and relaxation levels.