sömntryckets

Sömntrycket, also known as sleep pressure or sleep drive, refers to the physiological need for sleep that builds up during wakefulness. This concept is central to understanding the regulation of sleep and wakefulness, primarily governed by the body’s internal circadian rhythm and the accumulation of adenosine, a chemical that increases in concentration as we remain awake.

Adenosine gradually builds up in the brain throughout the day, binding to receptors that promote drowsiness and inhibit alertness. As adenosine levels rise, so does the subjective feeling of sleepiness, which is commonly experienced as a desire to rest or sleep. Conversely, sleep itself reduces adenosine levels, contributing to the feeling of refreshment upon waking.

The concept of sleep pressure is closely linked to the two-process model of sleep regulation, which posits that sleep is controlled by two interacting systems: the circadian process (Process C) and the homeostatic process (Process S). Process S, or sleep pressure, reflects the body’s need for recovery after wakefulness, while Process C aligns with the body’s internal clock, influencing alertness at different times of the day.

Factors such as sleep deprivation, irregular sleep schedules, and certain medications can disrupt the balance of sleep pressure, leading to increased daytime sleepiness or insomnia. Understanding sleep pressure helps in managing sleep habits, improving sleep quality, and addressing conditions related to disrupted sleep-wake cycles.