Narcolepsy occurs when the hypocretin (orexin) neurons secreted in the brainstem are lost, often through an autoimmune mechanism. As the wakefulness-regulating system breaks down, sudden sleep attacks during the day, cataplexy (loss of muscle strength triggered by emotions such as laughter or surprise), and sleep paralysis or hypnagogic hallucinations when falling asleep or waking up appear together. Unlike simple sleep deprivation or fatigue, the symptoms recur even with sufficient sleep.

Oriental Medicine Clinic Perspective

In Korean medicine, the spleen (脾) is considered to govern consciousness and concentration. When spleen qi (脾氣) becomes weak, clear energy cannot rise upward (a disturbance of the ascending-clear and descending-turbid flow), so the brain and mind cannot maintain wakefulness, and drowsiness and lethargy pour in even during the day. When a deficiency of heart qi (心氣) is added, declining concentration and memory overlap and the symptoms deepen further.