sömnfasen
Sömnfasen refers to a stage of sleep. Sleep is a naturally recurring state of mind and body, characterized by altered consciousness, relatively inhibited sensory activity, reduced muscle activity and inhibition of nearly all voluntary muscles during rapid eye movement (REM) sleep, and reduced interactions with surroundings. Sleep is characterized by several distinct stages, which alternate throughout the night. These stages are broadly categorized into non-rapid eye movement (NREM) sleep and REM sleep. NREM sleep is further divided into stages N1, N2, and N3, which represent progressively deeper levels of sleep. Sömnfasen typically encompasses one of these specific stages. During NREM stage N1, which is the lightest stage of sleep, individuals may experience hypnic jerks. Stage N2 is characterized by sleep spindles and K-complexes, which are believed to play a role in memory consolidation. Stage N3, also known as slow-wave sleep or deep sleep, is the most restorative stage, crucial for physical repair and growth. REM sleep is characterized by rapid eye movements, vivid dreaming, and muscle atonia. The cyclical progression through these sömnfaser throughout the night is essential for overall health and cognitive function. The duration and proportion of each sömnfasen can vary based on age, sleep deprivation, and other physiological factors.