Where the Donguibogam describes the spirit as a conductor harmonizing physical functions, modern medicine explains this dynamic through the complex interplay of the brain, the autonomic nervous system, and the endocrine system. Under stress, the body initiates the fight-or-flight response, triggered by excessive stimulation of the hypothalamic-pituitary-adrenal axis and the autonomic nervous system, especially the sympathetic nervous system.
Persistent stress causes the hypothalamus to secrete corticotropin-releasing hormone, prompting the pituitary gland to stimulate the adrenal cortex and release excess stress hormones, including cortisol. While cortisol temporarily mobilizes energy and manages inflammation, sustained elevation suppresses immunity, triggers systemic inflammation, and negatively alters brain function. In particular, it induces functional and structural changes in the hippocampus and the amygdala, worsening psychiatric symptoms such as anxiety and depression.
Stress also compromises autonomic nervous system balance. When the sympathetic nerve becomes hyperactivated, heart rate and blood pressure increase, muscles contract, and digestion slows. This mechanism produces tension headaches, stiffness in the neck and shoulders, and digestive disturbances like irritable bowel syndrome with bouts of bloating, diarrhea, or constipation. Meanwhile, the parasympathetic nerve, which directs rest and digestion, is suppressed. With sympathetic dominance, the body's regenerative processes are impeded, leading to chronic fatigue and a reduced ability to recover from minor daily strain.
Furthermore, the brain and digestive tract maintain continuous communication along the gut-brain axis. Chronic stress disrupts the gut microbiota, which elevates intestinal mucosal permeability and encourages inflammatory responses. Because roughly 90 percent of the body's serotonin is synthesized in the digestive tract, an imbalance in these gut-derived neurotransmitters feeds back into brain function and emotional regulation, sustaining a negative cycle.
Modern medicine mirrors the Donguibogam view that the spirit oversees vital activity by framing it as integrated brain function across the nervous system, endocrine system, and immune system. Rather than merely suppressing isolated symptoms, supporting long-term health requires regulating the stress response and restoring autonomic nervous system balance so body and mind can recover together.
