Question

Alpha waves on the EEG are seen during which state?

• A. Sleep
• B. REM movements
• C. Relaxed state
• D. Active state

Hint:

8-13 Hz alpha rhythm appears awake, relaxed, with eyes closed.

Answer 1

The Correct Option is C

Step 1: Rank the EEG rhythms by frequency: beta (fast, alert), alpha (intermediate, relaxed), theta and delta (slow, drowsy and deep sleep). The question asks where alpha fits.
Step 2: Alpha activity at 8 to 13 Hz appears over the occipital region when the subject is awake but calm, eyes shut, and not concentrating on anything in particular. This quiet, restful condition is the relaxed state, so that option is correct. Opening the eyes or concentrating abolishes alpha (alpha block) and brings in beta.
Step 3: Remove the distractors. The active, focused state generates beta waves, not alpha. Ordinary sleep brings slow theta and delta waves. REM sleep produces a desynchronised low-voltage fast pattern. None of these is the alpha rhythm, confirming the relaxed state as the answer.
\[\boxed{\text{Relaxed state}}\]