The world of sleep is incredibly dynamic, even though it appears as a serene, restful state from the outside. Our brains orchestrate a fascinating symphony of activities during various sleep stages, each with its distinctive characteristics and benefits.
Rapid Eye Movement (REM) sleep, comprising 25% of our sleep cycle, is when the brain becomes highly active despite the body's immobility. This stage is where most dreaming occurs, often vivid and story-like, owing to increased brain activity. The eyes move rapidly in various directions, and the body experiences heightened physiological processes similar to wakefulness, including increased heart rate and irregular breathing.
REM sleep is crucial for cognitive functions, memory consolidation, and emotional regulation. The duration of REM cycles lengthens as the night progresses, with each subsequent REM stage becoming longer.
Understanding these sleep stages is fundamental as sleep isn't a monotonous journey but a dynamic process transitioning between light and deep phases. The distribution of time spent in each stage varies throughout the night, contributing to the overall quality of sleep.
Now, regarding snoring, it's indeed an important sign that often goes unnoticed as it occurs during sleep. Detecting whether one snores is crucial, as it could indicate potential sleep disturbances or sleep apnea, impacting overall health. Tools like sleep apps, recording devices, or consulting with a sleep specialist can aid in identifying and addressing snoring issues for better sleep quality and health outcomes.
Non-REM Sleep Stages:
NREM sleep, constituting 75% of our total sleep, encompasses three distinct stages:
Stage 1 (N1): This marks the onset of sleep, where brain activity slows down, and the individual transitions from wakefulness to sleep. It's a light sleep phase, where you can easily be roused. During this stage, muscle activity decreases, and people might experience hypnic jerks or sudden muscle contractions, sometimes accompanied by a sensation of falling.
Stage 2 (N2): As sleep deepens, we enter N2, characterized by sleep spindles—short bursts of brain activity. Heart rate and breathing normalise, body temperature drops, and muscle tension relaxes further. This stage is pivotal in transitioning to deeper sleep.
Stage 3 (N3): Formerly referred to as stages 3 and 4, this is the deepest sleep phase. Brain waves slow down significantly, and it's challenging to wake someone in this stage. It's during N3 that the body undergoes substantial restoration and healing. Sleepwalking, sleep talking, bedwetting (in children), and certain types of vivid dreams or nightmares often occur during this phase.