K-complex is seen in which stage of sleep cycle-
Ans. is 'c' i.e., Stage 2 NREM * Full awake and alert state - Beta rhythm* Awake, eye closed and mind wandering but with less attentiveness - Alpha - rhythm* Stage 1 NREM - Theta rhythm* Stage 2 NREM - Sleep spindles, K complex* Stage 3 & 4 NREM (Deep sleep) - Delta rhythm* REM sleep - Beta rhythm and sometimes also reappearance of alpha rhythm.
REM
Stage 1 NREM
Stage 2 NREM
Stage 3 NREM
Nervous System