Meridian (Chinese medicine)


The meridian system is a concept in traditional Chinese medicine about a path through which the life-energy known as "qi" flows.
Meridians are not real anatomical structures: scientists have found no evidence that supports their existence. Major proponents of their existence have not come to any consensus as to how they might work or be tested in a scientific context.

Main concepts

The meridian network is typically divided into two categories, the jingmai or meridian channels and the luomai or associated vessels. The jingmai contain the 12 tendinomuscular meridians, the 12 divergent meridians, the 12 principal meridians, the eight extraordinary vessels as well as the Huato channel, a set of bilateral points on the lower back whose discovery is attributed to the ancient physician Hua Tuo. The collaterals contain 15 major arteries that connect the 12 principal meridians in various ways, in addition to the interaction with their associated internal organs and other related internal structures. The collateral system also incorporates a branching expanse of capillary-like vessels which spread throughout the body, namely in the 12 cutaneous regions as well as emanating from each point on the principal meridians. If one counts the number of unique points on each meridian, the total comes to 361, which matches the number of days in a year, in the moon calendar system. Note that this method ignores the fact that the bulk of acupoints are bilateral, making the actual total 670.
There are about 400 acupuncture points most of which are situated along the major 20 pathways. However, by the second Century AD, 649 acupuncture points were recognized in China. There are "12 Principal Meridians" where each meridian corresponds to either a hollow or solid organ; interacting with it and extending along a particular extremity. There are also "Eight Extraordinary Channels", two of which have their own sets of points, and the remaining ones connecting points on other channels.

12 standard meridians

The 12 standard meridians, also called Principal Meridians, are divided into Yin and Yang groups. The Yin meridians of the arm are Lung, Heart, and Pericardium. The Yang meridians of the arm are Large Intestine, Small Intestine, and Triple Burner. The Yin Meridians of the leg are Spleen, Kidney, and Liver. The Yang meridians of the leg are Stomach, Bladder, and Gall Bladder.
The table below gives a more systematic list of the 12 standard meridians:
Meridian name Quality of Yin or YangExtremityFive ElementsOrganTime of Day
Taiyin Lung Channel of Hand or Hand's Major Yin Lung MeridianGreater Yin Hand Metal Lung
Shaoyin Heart Channel of Hand or Hand's Minor Yin Heart MeridianLesser Yin Hand Fire Heart ; 11 a.m. to 1 p.m.
Jueyin Pericardium Channel of Hand or Hand's Absolute Yin Heart Protector MeridianFaint Yin Hand Fire Pericardium ; 7 p.m. to 9 p.m.
Shaoyang Sanjiao Channel of Hand or Hand's Minor Yang Triple Burner MeridianLesser Yang Hand Fire Triple Burner ; 9 p.m. to 11 p.m.
Taiyang Small Intestine Channel of Hand or Hand's Major Yang Small Intestine MeridianGreater Yang Hand Fire Small Intestine ; 1 p.m. to 3 p.m.
Yangming Large Intestine Channel of Hand or Hand's Yang Supreme Large Intestine MeridianYang Bright Hand Metal Large Intestine ; 5 a.m. to 7 a.m.
Taiyin Spleen Channel of Foot or Foot's Major Yin Spleen MeridianGreater Yin Foot Earth Spleen ; 9 a.m. to 11 a.m.
Shaoyin Kidney Channel of Foot or Foot's Minor Yin Kidney MeridianLesser Yin Foot Water Kidney ; 5 p.m. to 7 p.m.
Jueyin Liver Channel of Foot or Foot's Absolute Yin Liver MeridianFaint Yin Foot Wood Liver ; 1 a.m. to 3 a.m.
Shaoyang Gallbladder Channel of Foot or Foot's Minor Yang Gallbladder MeridianLesser Yang Foot Wood Gall Bladder ; 11 p.m. to 1 a.m.
Taiyang Bladder Channel of Foot or Foot's Major Yang Urinary Bladder MeridianGreater Yang Foot Water Urinary bladder ; 3 p.m. to 5 p.m.
Yangming Stomach Channel of Foot or Foot's Yang Supreme Stomach MeridianYang Bright Foot Earth Stomach ; 7 a.m. to 9 a.m.

Eight extraordinary meridians

The eight extraordinary meridians are of pivotal importance in the study of Qigong, T'ai chi ch'uan and Chinese alchemy. These eight extra meridians differ from the standard twelve organ meridians in that they are considered to be storage vessels or reservoirs of energy and are not associated directly with the Zang Fu, i.e. internal organs. These channels were first systematically referred to in the "Spiritual Axis" chapters 17, 21 and 62, the "Classic of Difficulties" chapters 27, 28 and 29 and the "Study of the 8 Extraordinary vessels" by Li Shi Zhen 1578.
The eight extraordinary vessels are :
  1. Conception Vessel -
  2. Governing Vessel -
  3. Penetrating Vessel -
  4. Girdle Vessel -
  5. Yin linking vessel -
  6. Yang linking vessel -
  7. Yin Heel Vessel -
  8. Yang Heel Vessel -

    Scientific view of meridian theory

Meridians do not exist: scientists have found no evidence that supports their existence.
According to Steven Novella, "there is no evidence that the meridians actually exist. At the risk of sounding redundant, they are as made up and fictional as the ether, flogistum, Bigfoot, and unicorns."
The National Council Against Health Fraud concluded that "he meridians are imaginary; their locations do not relate to internal organs, and therefore do not relate to human anatomy."

History

The concept of meridians are first attested in two works recovered from the Mawangdui and Zhangjiashan tombs of the Han-era Changsha Kingdom, the Cauterization Canon of the Eleven Foot and Arm Channels Zúbì Shíyī Mài Jiǔjīng) and the Cauterization Canon of the Eleven Yin and Yang Channels Yīnyáng Shíyī Mài Jiǔjīng). In the texts, the meridians are referenced as mài rather than jīngmài.