Non-REM 2

• Most common sleep stage during a normal night’s sleep.
• Appearance of sleep spindles
  • Short burst of waxing and waning rhythmic waves.
  • Amplitude of 20-100 microvolt.
  • Frequency of 12-16 Hz
  • The presence of sleep spindles is necessary and sufficient to define non REM 2 sleep
  • First appear in infants of 6-8 weeks old
  • Bilateral and synchronous
  • Maximum in the frontal and central regions
• Appearance of K complex
• Appearance of <20% Delta waves
• All sleep patterns in Non-REM 1 persist in Non-REM 2, except for slow rolling eye movements (SREM).

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Non REM 2 sleep with sleepspindles, K-complex and delta waves (average)

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