Translating Donguibogamβs concept of an unstable shen of the heart into modern medical terms shows a close connection to autonomic nervous system imbalance. When we experience stress or anxiety, the brain's amygdala and hypothalamus become active, excessively stimulating the sympathetic nervous system. You can think of the sympathetic nervous system as our body's emergency response system. To prepare for a fight-or-flight response, it declares a state of emergency throughout the body by raising the heart rate and blood pressure, suppressing digestive functions, and tensing muscles.
If this sympathetic hyperactivity fails to subside at night, sleeping comfortably is naturally difficult, as the relaxation driven by the parasympathetic nervous system needed for sleep cannot occur adequately. This is precisely why symptoms such as palpitations, shallow breathing, and muscle tension appear even before falling asleep. In particular, the sleep hormone melatonin should be secreted at night; however, continuous secretion of the stress hormone cortisol suppresses melatonin release, significantly lowering sleep quality. As the cycles of REM sleep and non-REM sleep are disrupted, deep sleep becomes elusive, leaving you in a repeated state of waking up unrefreshed.
In addition, neurotransmitter imbalances are an important factor. When the functions of serotonin, which regulates emotions and supports sound sleep, and gamma-aminobutyric acid (GABA), which suppresses excitation, decline, anxiety amplifies and falling asleep becomes difficult. Conversely, the activity of neurotransmitters that induce anxiety, such as norepinephrine, rises. What Donguibogam described as liver qi stagnation fueling the fire of the heart can be interpreted in modern medicine as stress and chronic tension disrupting neurotransmitter balance, causing hyperactivation of the brain, and placing a burden on the cardiovascular system.
Ultimately, insomnia and palpitations caused by anxiety are not simply issues of the mind, but the outcome of a complex imbalance spanning the brain, nervous system, and hormonal systems. Because our body is organically interconnected, trouble in one area disrupts the harmony of the whole. Restoring this balance is therefore the key to escaping sleepless nights and regaining comfort.
