See Also
Sleep cycle§
A good sleep cycle is important for overall health and well-being. A normal sleep cycle is composed of 4 to 6 cycles of 90 minutes.
- 4 cycles = 6 hours
- 5 cycles = 7 hours 30
Characteristics§
2 main phases characterize a sleep cycle, Slow-wave-sleep and Rapid Eye Movement.
Slow-wave-sleep (also known as deep sleep) is a period of time where the brain performs memory consolidation and strengthens declarative memory. Memory consolidation is a process where short-term memories are transferred to long-term storage, integrating new information with existing knowledge.
REM (Rapid Eye Movement) sleep is characterized by:
- Rapid eye movements
- Vivid dreams
- Muscle atonia (temporary paralysis)
- Emotional memory processing
- Creative problem solving
Sleep Stages§
A complete sleep cycle progresses through these stages:
- Stage 1 (N1) - Light sleep, transition (5-10%)
- Stage 2 (N2) - Deeper sleep, heart rate slows (45-55%)
- Stage 3 (N3) - Deep sleep / Slow-wave sleep (15-25%)
- REM - Rapid Eye Movement (20-25%)
Functions of Sleep§
Physical Restoration
- Tissue repair and growth
- Muscle recovery
- Immune system strengthening
- Hormone regulation
Mental Functions
- Memory consolidation
- Learning enhancement
- Emotional regulation
- Toxin removal from brain (glymphatic system)
Sleep Hygiene§
Good practices:
- Consistent sleep schedule
- Dark, cool room (16-19°C)
- No screens 1 hour before bed
- Avoid caffeine after 2pm
- Regular exercise (but not before bed)
- Relaxation techniques
Consequences of sleep deprivation:
- Cognitive impairment
- Weakened immune system
- Increased risk of chronic diseases
- Mood disturbances
- Decreased performance
Recommended Sleep Duration§
- Adults: 7-9 hours
- Teenagers: 8-10 hours
- Children: 9-12 hours
- Infants: 12-16 hours
See Also§
- Alzheimer - Sleep’s role in preventing neurodegenerative diseases
- Psychologie - Impact on mental health
Dernière mise à jour: 2026-01-01
—The Gardener