EEG shows "Sleep Spindles" in this stage of NREM sleep
(B) II > Stage II of NREM sleep is characterized by sleep spindles on EEC. Sleep spindles are bursts of alpha-like, 10-14Hz., 50 mV waves.> When a person falling asleep enters stage I of "NREM, the EEG shows low-amplitude, high frequency waves. As the progression from Stage I to Stage IV of NREM occurs, the frequency of waves decreases while the amplitude increases progressively.
I
II
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IV
Nervous System