Insomnia means any kind of difficulty with sleep. Some people have trouble goinmg to sleep, others staying asleep, and yet others have disturbed sleep. In Oriental Medicine sleep happens during a Yin state when the Hun (the part of the Shen which resides in the Liver) moves slightly away from it's residence in the Liver. So many Liver disharmonies can affect sleep.
If the Liver Blood is insufficient the Hun may move too far away with the result of disturbing dreams or nightmares. Excess of Liver Heat or Fire can prevent sleep from happening at all. The Heart can also be the culprit because all emotional Qi is gathered by it and then distributed to the other parts of the Shen. The Spleen is affected by the worry category of emotional Qi and can affect both the Qi and Blood of the Heart and/or Liver.
As with all diagnoses, treatment is done by use of acupuncture, herbal medicines, tuina and any or all of the treatment methods in Oriental Medicine.