Modern medicine expresses the wisdom of Donguibogam in slightly different terms. Shallow sleep, marked by frequent awakenings and constant dreaming through the night, is called sleep fragmentation. While asleep, our brain does not simply rest; it undergoes complex processes to organize and store daytime information and restore the body. This occurs through a sleep cycle with multiple sleep stages: REM sleep and non-REM sleep. REM sleep is primarily the stage where dreams occur, while during the deep sleep stage of non-rapid eye movement sleep, physical recovery and growth hormone secretion actively take place.
However, when sleep becomes fragmented, this sleep cycle is disrupted, preventing sufficient deep sleep or excessively increasing the proportion of REM sleep. In particular, frequently waking from shallow sleep leaves the REM sleep stage immediately preceding awakening more vividly stored in memory, making it easy to feel like you did nothing but dream all night. This signals that the brain is not getting proper rest and continues to remain active.
Several scientific causes lie behind this phenomenon. Stress and anxiety cause an autonomic nervous system imbalance. The autonomic nervous system is divided into sympathetic nerves and parasympathetic nerves; the sympathetic nerve governs tension and arousal, while the parasympathetic nerve governs relaxation and rest. Persistent stress excessively activates sympathetic nerves, making it difficult to fall asleep, and even after falling asleep, the brain cannot fully relax, resulting in repeated shallow sleep. Continued high nocturnal secretion of the stress hormone cortisol, which degrades sleep quality, is also a major factor.
Furthermore, an imbalance in brain neurotransmitters plays a role. Gamma-aminobutyric acid (GABA) is an essential neurotransmitter that inhibits brain excitation and induces sleep. When GABA secretion is impaired by stress or improper lifestyle habits, falling asleep becomes difficult, resulting in shallow sleep. The same occurs when the secretion of sleep-inducing hormones such as serotonin or melatonin is inhibited.
When Donguibogam speaks of gallbladder qi deficiency with timidity, rather than referring solely to the gallbladder as an isolated organ, it can be understood as describing a state of mind vulnerable to stress, sensitive, prone to anxiety, and struggling to make decisions. This psychological state ultimately affects our autonomic nervous system, hormones, and neurotransmitters, lowering sleep quality. In other words, mental instability weakens gallbladder qi, which manifests in forms like modern medicine's sleep fragmentation. Therefore, restoring harmony between body and mind is the most important key to deep sleep.
