Apnea

Snoring itself — is the vibration of the soft tissues of the throat due to partial narrowing of the airways. It can be either harmless or a manifestation of obstructive sleep apnea syndrome (OSAS).

Sleep phases. Phase 3 and 4 (the so-called deep slow sleep, delta sleep) — are critically important stages for the recovery of the body, immune function, hormonal regulation, and memory.

During deep sleep, breathing and heart rate become the most regular, and muscle tone is minimal.

What snoring and apnea do. With severe snoring and breathing pauses (apnea), the brain is periodically forced to awaken to more superficial stages of sleep to restore breathing. This is called micro-awakenings.

As a result, the structure of sleep is fragmented: a person seems to sleep all night, but their brain never truly "falls" into full-length episodes of phases 3–4.

Polysomnography shows that people with severe apnea have significantly reduced or absent slow sleep.

Why this is important. The absence of deep sleep leads to chronic fatigue, decreased cognitive functions, hormonal imbalance (cortisol, testosterone, growth hormone), and increased risk of diabetes and cardiovascular diseases.

Even if snoring is "simple" (without apnea), its constant vibrations and episodes of partial awakening can also shorten the phases of deep sleep, but not completely exclude them.

During deep sleep phases (NREM 3–4), a special brain cleansing mechanism is activated – the so-called glymphatic system. It was described relatively recently and serves as a "sanitation network" for the central nervous system.

How it works. In a waking state, the intercellular space of the brain is relatively narrow, and the circulation of interstitial fluid is limited. During deep sleep phases, under the influence of decreased norepinephrine levels and overall relaxation of the body, the intercellular gaps expand almost twice. This allows cerebrospinal fluid to actively wash the brain tissues, flushing out metabolic byproducts: excess ions, toxins, damaged proteins, including β-amyloid and tau proteins.

It has been established that it is during the night that the brain eliminates up to 60% of the metabolites accumulated during the day.

Why this is important. Amyloid proteins are normally constantly formed as a byproduct of neuronal activity.

If the glymphatic system is not functioning well (for example, due to chronic sleep deprivation, sleep apnea, or disruption of deep sleep phases), amyloids begin to accumulate in the brain tissues.

These deposits form amyloid plaques, which are considered a key pathological factor in Alzheimer's disease and other neurodegenerative disorders.

Similarly, the accumulation of pathologically altered tau proteins is associated with the development of so-called tauopathies.

Implications for health. Lack of sleep, especially a deficit in phases 3 and 4, sharply increases the risk of cognitive decline.

Studies have shown that even one night of poor sleep leads to a measurable increase in β-amyloid concentration in the cerebrospinal fluid.

Chronic sleep deprivation exacerbates inflammation, reduces neuroplasticity, and accelerates degenerative processes.

Thus, deep sleep is not just "rest," but an active phase of neurodetoxification. It is critically important for the prevention of memory diseases and the maintenance of long-term cognitive health.