Sleep spindle is seen in-: (A) REM, (B) Stage 1 NREM, (C) Stage 2 NREM, (D) Stage 3 NREM
Answer is C. Ans is 'c' i.e., Stage 2 NREM o Full awake and alert state - Beta rhythmo Awake, eye closed and mind wandering but with less attentiveness - Alpha - rhythmo Stage 1 NREM - Theta rhythmo Stage 2 NREM - Sleep spindles, K complexo Stage 3 & 4 NREM (Deep sleep) - Delta rhythmo REM sleep - Beta rhythm and sometimes also reappearance of alpha rhythm.