Jueyin Liver - Functions

The main functions of the Liver are to store blood and ensure the smooth flow and direction of Qi movement in the body.  It is also said to contribute to our body’s resistance to external pathogenic influences.  “The Liver is the origin of courage and resoluteness if it is in a state of good health.” (Maciocia).  It is also believed that the Liver influences our ability to plan our lives.

The functions of the Liver are:

Storing of blood
Ensuring the smooth flow of Qi
Controls the sinews
Shows its health on the nails
Opens into the eyes
Houses the Ethereal Soul (Hun)
Effects dreams

Storing of blood

The Liver is the most important organ for storing blood, it regulates the volume of blood in the whole body.  

Alters blood volume according to physical activity
The Liver stores blood when the body is at rest or sleep (between 1-3am), when it is active it allows the blood to move to the muscles.  
These functions (ensuring proper nourishment to certain tissues at certain times) has a great effect on the energy one has.  If the blood flows properly to the skin the body’s natural protection against external pathogenic factors will be strong (although the most important functions of protection are preformed by the defensive Wei Qi and the Lungs).
The storage of blood strongly influences menstruation
Menstruation will be normal if the Liver is storing blood properly.  If the blood is deficient there will be amenorrhea or oligomenorrhea.  If there is heat or a Liver excess the blood can move recklessly and cause menorrhagia or metrorrhagia.  Bar none the Liver is the main organ of gynecological functioning.  Most problems associated with womens reproductive systems are due to Liver malfunction.  Liver Qi stagnation can lead to blood stagnation which can cause painful menses, PMS, and clotting of menstrual blood.  The storage of blood also greatly influences the functioning of the Ren and Chong meridians.
The blood of the Liver particularly takes care of nourishing the eyes and tendons.  If there is a Liver blood deficiency one will see dry eyes, blurred vision, muscle cramps, and stiffness.
Diseases of the blood can effect the Liver, and Liver diseases can effect the blood causing various skin problems.

Ensuring the smooth flow of Qi

The Liver ensures the smooth flow of Qi throughout the entire body, in all organs, in all directions.  Disorders of this function are the most common patterns seen in practice.  Every organs Qi has a particular direction in which it is supposed to flow.  The direction of movement of Liver Qi is upwards and outwards in all directions to ensure the smooth flow everywhere, therefore it effects and helps regulate every organ.  

Wood grows in every direction.

strongly effects emotions
If Liver function is normal, people will have smooth flowing emotional states favoring happiness.  If the flow of Qi is stagnated, frustration, depression, irritability, anger, hypochondriac pain, stuffiness in the chest, lumps in the throat, abdominal distension can occur.  Various pre-menstrual syndrome symptoms will also arise, i.e. mood swings, & breast tenderness.  Therefore emotions effect the smooth flow of Liver Qi, and stagnated Liver Qi effect the emotions adversely.
effects the digestion of food by the Spleen and Stomach
If the Qi is not flowing smoothly (i.e. from emotions), the Spleen and Stomach have trouble performing their digestive functions.  If the Liver Qi is stagnated it can overact on the Stomach causing a reversal in the downward movement of Stomach Qi causing vomiting, belching, and nausea.  If it overacts on the Spleen it will effects its natural upward flow of Qi and cause diarrhea.  These digestive disturbances are referred to as ‘wood overacting on earth’ from the 5 element theory.  
Normally the smooth flow of Liver Qi aids the mid Jiao in digestion.
Flow of bile
If Liver Qi is stagnated the flow of bile can get obstructed resulting in a bitter taste in the mouth, belching, or jaundice.

Controls the sinews

The sinews ability to contract and relax depends on the nourishment from Liver blood.  If Liver blood is deficient it can cause spasms, stiffness, reduced range of motion, numbness, muscle cramps, tremors, tetany, seizures, and reduced strength in the limbs.  This is closely related to proper functioning of the Spleen and blood production as the Spleen controls the muscles.

Shows its health on the nails

The nails are considered to be an extension of the sinews, therefore they are closely related to the state of the Liver blood.  If Liver blood is deficient the nails will become dry, cracked, dark, indented, and generally unhealthy.  

Opens into the eyes

The eye is the special sensory organ which is directly connected to the Liver.  They require nourishment from the Liver blood in order to see properly.  If Liver blood is deficient there can be blurred vision, myopia, floaters, colour blindness, dryness, soreness, itchiness, and other eye disorders.  If the Liver has heat the eyes can get blood shot, painful and burning.  If the Liver has created internal Wind the eyeballs may turn upwards or shake.

Other organs also effect the proper functioning of the eye:  Heart, Kidneys, Lungs, Gallbladder, Bladder, and Small Intestine.

The Kidney Essence plays a big role in the nourishment of the eyes, many chronic ocular disorders are due to the decline of Essence.  The Heart through the Shen is also a factor in eye health.  This is why the state of a persons spirit can be observed through the eyes.

Houses the Ethereal Soul (Hun)

The Liver is the residence of the Ethereal Soul (Hun).  This is most closely related to the spirit without form.  The Ethereal soul does not die with the organic body.  It is non-material, therefore Yang in nature.  

Its counterpart, the Corporeal soul (Po) which resides in the Lungs would be the Yin, or material aspect to our being.  It dies with the body.  

The Ethereal soul is said to influence the planning of our lives and the feeling of purpose.  Lack of direction or purpose is due to a deficiency of the Liver, this causes the soul to be uprooted and float resulting in confusion, lack of visionary conclusions, and wandering.  Some say that if Liver Yin and/or blood are deficient enough that the person will have a sensation of floating just before going to sleep (some also consider this to be a healthy state).