While the Donguibogam described harmony among the lung, kidney, and spleen, modern medicine explains these phenomena from a microscopic perspective. Hoarseness, throat pain, a foreign body sensation, and vocal cord nodules stem from complex causes that can be understood through three main aspects.
First is the microenvironment of the vocal cords. Vocal cord nodules arise primarily when excessive vocal use or improper vocal habits cause ongoing friction and inflammation on the vocal cord mucosa. Much like calluses forming on the palms, repeated impact causes the vocal cord mucosa to thicken and develop fibrosis. A deficiency in body fluids leaves the vocal cord mucosa dry and more vulnerable to friction. In modern terms, this corresponds to a thinning mucus layer and decreased water content across the vocal cord mucosa. A dry mucus layer loses its lubricating capacity, making it prone to damage from minor impacts and slowing its rate of recovery.
Second is the role of the autonomic nervous system. Daily stress and tension cause autonomic nervous system imbalance, which can trigger excessive contraction in the muscles surrounding the vocal cords. This often presents as muscle tension dysphonia, where sustained tightness in the neck and laryngeal muscles prevents proper vocal cord vibration, resulting in hoarseness or pain. The qi stagnation and binding described in the Donguibogam shares a similar context with these physical symptoms caused by autonomic dysregulation. Stress also aggravates acid reflux, including gastroesophageal reflux disease and laryngopharyngeal reflux, allowing gastric acid to travel up the esophagus to irritate the vocal cords directly and cause inflammation. This process is recognized as a leading cause of vocal cord nodules and chronic laryngitis.
Third is the relationship with systemic health. The lung, kidney, and spleen in the Donguibogam correspond closely to the respiratory system, endocrine system, digestive system, and immune system. When lung function weakens, shallow breathing fails to supply adequate airflow to the vocal cords, placing extra strain on them during speech. Kidney function relates to overall endocrine regulation, including thyroid hormone, and hormonal imbalance alters the fluid metabolism and elasticity of the vocal cord mucosa, producing vocal changes. Meanwhile, spleen function governs immunity, digestion, and nutrient absorption. A chronic inflammatory state or nutritional imbalance delays tissue repair in the vocal cords and increases the likelihood of nodule formation. When systemic conditioning declines, vocal health suffers as a whole. Vocal changes are therefore delicate indicators reflecting the health of the entire body.
