I know that a lot of people have been having bad dreams this year. These are a few explanations from a TCM point of view.
In the book Dragon Rises, Red Bird Flies by Dr. Leon Hammer, he addresses nightmares. He writes that weak Shen of the Heart and poor Gall Bladder function causes them. The Gall Bladder has the role of decision-maker in TCM, and one could extrapolate that the loss of control in a nightmare is an extension of Gall Bladder illness.
Illness in the body can result in problems with sleep and generate specific dreams. Heart Fire disturbing the Spirit causes insomnia. Dream-disturbed sleep is due to Liver Blood deficiency or Kidney yin deficiency. A corresponding problem in the body manifests in dreams. It is the Spirit’s reaction to the problem. In TCM, the mental and physical are linked. There is a direct connection between dreams and physical state.
In Yellow Emperor’s Classic of Medicine, it says that people’s dreams can reflect the state of energy and also help a doctor to diagnose a person’s illness. To assess one’s energy state, for example, a doctor can evaluate the Spleen Qi. The Spleen Qi is in excess if one dreams of the construction of a wall. The Spleen Qi is deficient if one dreams of starving. As an example of diagnosis, Qi Bo says to Huang Di, “if one dreams of flying, there is an excess in the upper body, if one dreams of falling, there is an excess in the lower body” (p. 66).
So, dreams can provide valuable insight to ourselves and those who want to help heal us.