The International Association for the Study of Pain defines pain as “an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.”1 Pain is unpleasant but the feeling of pain is an adaptive self-protection against further injury and it is a warning sign of actual or potential tissue damage or of more serious issues. Chronic pain refers to pain that lasts or recurs for more than 3 to 6 months.2 According to data from the Centers for Disease Control and Prevention, in 2019, there were 20.4% of the adult population in the United States suffered from chronic pain and 7.4% of adults whose life and work activities were affected by their chronic pain for at least 3 months.3
Chronic pain is one of the major complaints from patients seen in all acupuncture clinics. The most common principle to treat pain with acupuncture is to activate channels to relieve pain; however, little attention has been paid to treating patient’s shen when treating their pain.
This article is an introduction to the incorporation of the treatment of shen when treating chronic pain with acupuncture. The discussion of shen and its treatments in this article are based on the review and study of the theories and principles in the ancient classics of traditional Chinese medicine (TCM).
2 Role of shen in chronic pain
2.1 Shen, the governor of life that makes us be able to feel pain
Shen is the governor of life; it controls all physical and mental activities. Shen is defined in Chapter 8 of Ling Shu (《灵枢》 Spiritual Pivot) that “what the heaven has given me (human) is the de (德); what the earth has given me is the qi. When the de flows and acts on the qi, essences (jing 精) are created. When two essences (of yin and yang) clash into each other, it is called shen (神). That which comes and goes following the shen is the ethereal soul (hun 魂); that which enters and leaves together with the essence is the corporeal soul (po 魄); that which is responsible for all affairs is called the heart. When the heart reflects on something, that is called intention (yi 意); When the intention is stored, that is called will (zhi 志); If the will longs for changes, that is called pondering (si 思); If the pondering results in far reaching plans, that is called consideration (lü 虑); If the considerations guide one’s handling of the affairs, that is called wisdom (zhi 智).”4,5
In other words, Ling Shu describes that shen is essentially the interaction between yin and yang. Hun is the pre-existing spirit in the universe and it follows shen; it is called the yang shen (阳神). Po is the spirit from the essences of yin and yang and it enters and stays with shen; it is called the yin shen (阴神). As shen is hosted by the heart, we also refer it as the heart shen. The intention (yi 意), will (zhi 志), pondering (si 思), consideration (lü 虑), and wisdom (zhi 智) are derived from the activities of heart shen. Shen (神), hun (魂), po (魄) are not parallel with yi (意), zhi (志), si (思), lü (虑), and zhi (智). This concept is very clearly stated in Chapter 8 of the Su Wen (《素问》 Basic Questions), that the heart is the sovereign of all organs and it governs the shen and its associated activities.6
Shen enables all physical and mental activities. In TCM, pain is one of the perceptions controlled and conducted by shen, or heart shen. Chapter 74 of the Su Wen states that the symptoms of pain and itch belonged to the disorders of the heart shen.6 So, heart shen enables people to feel, recognize, and respond to stimuli and changes that happen to their body and this is the basic understanding of the mechanism of pain in TCM.
2.2 Disorders of shen in chronic pain
There is a saying that should resonate with sufferers: pain is fact and fact is pain. Patients’ shen is involved in their chronic pain. A disorder of shen is often present in patients with chronic pain; when a patient has chronic pain, his/her shen is not in a normal state.
The perception of pain involves the sufferers’ psychological and physical experiences. How much pain a sufferer feels, how much pain he or she reports and how his/her body and mind respond to the pain are based on individual pain threshold and associated physical and mental experiences.
The disorders of shen can cause the sufferers to have psychological manifestations. Patients with chronic pain often have accompanying mental and emotional symptoms such as anxiety and/or depression.7 Furthermore, Chapter 74 of the Su Wen states that symptoms of disorientation, confusion, and convulsion belong to the fire (which disturbs the heart). Pain and itching belong to the disorders of the heart where the shen dwells.6
The disorders of shen can also cause the sufferers to have physical responses such as uncoordinated movements, over-tensed muscles and tendons, muscle weakness, decreased range of motion, decreased pain threshold, and etc. These physical manifestations are the results of shen’s disorders; they may or may not have a direct connection to the disease that causes the pain. These physical manifestations could misguide a medical diagnosis and, as a result, delay the healing or recovery of the illness that causes the chronic pain.
Patients with a disorder of shen can recognize, report/rate, and respond to pain abnormally. Patients with disorders of shen can exaggerate or understate the pain level that they experience.
In a nutshell, the disorders of shen could distort a person’s subjective feelings and perceptions, especially pain. The disorders of shen can negatively affect how the patients feel or recognize pain and how they report their pain level.
Shen is the spirit created by the interaction of yin and yang and there are two kinds of shen: the yang aspect of shen is called hun, whereas the yin aspect of shen is named po.8 The disorder of shen can be subdivided into the disorders of hun and po.
2.2.1 Disorders of hun
Hun, also known as the yang shen, is stored in the liver. It controls the functions and feelings from all formless and invisible elements of our body such as qi, thoughts, emotions, wisdom, conscience, judgement, and etc. It is stated in Chapter 8 of the Ling Shu, that “when grief and sorrow attack the center, this will harm the hun soul. The patient will be mad, forgetful, or not witty; his judgements are not proper.”4
Depression, anxiety, and exaggeration of pain level in patients with chronic pain are related to the disorders of hun. A patient with disorder of hun usually reports the pain intensity as more severe during daytime. Patients with disorder of hun could lack common sense or proper judgement in managing their pain in their daily life. Some patients with the disorder of hun could be obsessed with the belief that their diseases are much more severe and much more life-threatening than the actual diagnosis and prognosis.
2.2.2 Disorder of po
Po, also known as the yin shen, is stored in the lung. It controls the body’s involuntary functions such as heartbeat, blood pressure, body temperature, breathing, coordination of body movements, muscle tension, and pain threshold.
When a patient has a disorder of po, he or she is not nimble. The patient may have uncoordinated movement, decreased range of motion of body parts, decreased pain threshold, increased tension in muscles or weakness of muscles, and/or sleep apnea. Patient with the disorder of po usually report that the pain intensity is more severe during sleep time at night. It is commonly found that the pain level or the degree of musculoskeletal functions reported by patients with disorder of po does not match with their injuries or tissue damages diagnosed by clinical evaluation, diagnostic imaging, and other medical examinations.
3 Principles of treatment of shen in acupuncture
The treatment of shen should be incorporated in the acupuncture treatments of pain, especially for chronic pain. The goal is to regulate the shen back to its normal state.
Chapter 1 of the Ling Shu emphasizes the importance of the treatment of shen as follows: “The essential of performing acupuncture treatment is easy to talk about but it is difficult to perform. Unrefined practitioners are stuck on the physical appearance of the needling techniques while the outstanding practitioners hold shen in their treatments.”4
Guarding or treating shen is the key to an effective treatment for chronic pain. There are many ways to restore the normal state of shen but the essential principles are harmonizing the yin and yang by needling techniques and regulating the hun and po.
3.1 Harmonizing yin and yang by needling techniques
It is stated in Chapter 5 of the Su Wen, that the law of yin and yang is “the natural order of the universe, the foundation of all things and all changes, the root of life and death, and the palace of the shen.”6 Furthermore, Chapter 8 of the Ling Shu states that shen is the interaction of the essences of yin and yang (the interaction includes the interaction itself and the results of the interactions).4 Therefore, harmonizing yin and yang is essential to maintain or restore the normal state of shen.
Restoring the normal state of shen in each selected point of the acupuncture treatment is the way to restore the normal state of shen of the whole body.
The acupuncture points existing on our body are not designed only for acupuncture treatments; each point has its own shen and has the function to communicate. The points are specific sites through which the qi of the zang fu organs and the qi of the meridians are transported to the surface of the body so that the qi between the exterior and interior of the body, and the qi between the body and nature could be connected and be in communication. It is stated in Chapter 1 of the Ling Shu, that the so-called points are the locations where the shen qi passes, exits and enters.4 Each point is a very important gateway for the communication of shen between the interior and exterior of the body and also between the body and nature. Therefore, and more importantly, our body is part of the whole universe.
When the shen of a point is not normal, it manifests itself as a disorder of its corresponding zang fu organ systems, and the abnormal state can cause miscommunication between the body and nature on the shen level. Chapter 68 of the Su Wen further states that when the passing (ascending and descending), exiting, and entering movements are disabled, the generating and transforming of shen (shen ji 神机) will be destroyed, and the setting up of qi (qi li 气立) will be secluded and destructed.6
It is essential to use proper needling technique to normalize the shen. There are many needling techniques taught in the TCM ancient classics, ancient books, and modern lectures. No matter which needling technique is employed, the goal is to normalize the shen by harmonizing the yin and yang at each selected point.
The principle of the needling technique for treating the shen is described in Chapter 9 of the Ling Shu, that the meaning of de qi (qi arrival 得气) is to make the yang qi move to the deep and to bring the yin qi to the shallow to make a good communication and interaction between the yin and yang, hence the shen qi is guarded and the evil qi stopped.4
3.2 Regulating the hun and po
Liver hosts the hun. Any pathological disorders of the liver can result in the dysfunction of the hun. When treating and regulating the hun in patients with chronic pain, we should focus on the liver. Soothing the liver, clearing the liver heat, and nourishing the liver blood are common treatment methods to regulate the liver and, therefore, to restore its normal hosting function of the hun.
Lung hosts the po. Any pathological changes of the lung such as lung qi deficiency, lung yin deficiency, invasion of the lung by cold, and etc. will cause malfunctions of the lung in hosting po. When treating and regulating the po, we should focus on the treatment of lung’s descending and dispersing functions. Tonifying the lung qi, nourishing the lung yin, dispelling cold from the lung are the most common treatment methods.
4 Practice of treating the shen in acupuncture
4.1 Specific points used for the treatment of shen
Although all acupuncture points are the sites where shen qi passes, exits, and enters, some of them are specifically associated with the shen, hun, or po of the whole body. Using these acupuncture points is helpful to treat shen in general.
It is difficult to discuss the systematic application of points for the treatment of shen of the whole body since the records of such treatment in the TCM ancient classics are scattered and not well explained. This article only provides a list of points (Table 1) with names that give clues that they could be beneficial for the treatment of shen.
Table 1 -
Suggested acupuncture points
||Meaning of name
||Functions of point
|Shenmen (神门 HT 7)
||Door of the shen
||Nourish heart and calm shen
|Pohu (魄户 BL 42)
||House of po
||Clear lung and calm po
|Shentang (神堂BL 44)
||Hall of shen
||Clear heart and calm shen
|Hunmen (魂门 BL 47)
||Door of hun
||Nourish liver and calm hun
|Yishe (意舍 BL 49)
||House of thoughts
||Strengthen spleen and clear thoughts
|Zhishi (志室 BL 52)
||House of will power
||Tonify kidney and strengthen will power
|Benshen (本神 GB 13)
||Origin of shen
||Regulate and calm shen
|Dazhong (大钟 KI 4)
||Great bell (in a Buddhist temple)
||Arrest po and awake hun
|Zhubin (筑宾 KI 9)
||Playing music to entertain guests
||Relieve depression and restore hun
|Shenfeng (神封 KI 23)
||Domain of shen
||Regulate and calm shen
|Lingxu (灵墟 KI 24)
||City of shen in ancient time
||Regulate and restore shen
|Shencang (神藏 KI 25)
||Vault of shen
|Lingtai (灵台 DU 10)
||Stage of shen
||Clear mind and calm shen
|Shendao (神道 DU 11)
||Passage of shen
||Clear mind and calm shen
|Shenting (神庭 DU 24)
||Courtyard of shen
||Clear mind and calm shen
|Dadun (大敦 LV 1)
||Sooth liver and calm hun
|Xingjian (行间 LV 2)
||Clear liver heat and calm hun
|Taichong (太冲 LV 3)
||Great rushing (of blood)
||Nourish liver blood and foster hun
|Zhangmen (章门 LV 13)
||Door to management
||Clear liver, remove liver stagnation, and calm hun
|Tianfu (天府 LU 3)
||Palace of heaven
||Promote lung’s dispersing and descending functions, calm po
|Xiabai (侠白 LU 4)
||A knight fighting for the west
||Clear lung and restore po
|Jianshi (间使 PC 5)
||Order to clear boundaries
||Calm mind, regulate shen
4.2 Needling techniques for the treatment of shen
In the acupuncture treatment of shen, the principle of needling technique is to restore the normal state of shen in each selected point as discussed in the Section 2.1.
In question number 48 of the Nan Jing (《难经》 The Classic of Difficult Issues), it is stated that a person may have three kinds of deficiency and three kinds of excess.9 “Three” in this statement refers to “many.” A TCM syndrome identification is a comprehensive conclusion which describes the root cause of an illness. Whether a patient has been diagnosed with a deficient or excess syndrome, the shen state of each acupuncture point on this patient is independent of his/her syndrome identification and it could be in a deficient or an excess state itself. The shen state of each point may or may not match with the syndrome identification of the patient’s illness. For example, Taixi (太溪 KI 3) could be in a deficient state (soft) on a patient with low back pain due to qi and blood stagnation (an excess syndrome identification). Restoring the normal state of shen of the point selected for the treatment is the key.
4.2.1 Step 1: Palpating to determine the state of shen in each selected point
The practitioner should palpate the point to detect and determine the state of shen of that point before needling. In general, the state of shen in a selected point can be put into two categories: deficiency and excess. If the practitioner perceives softness like pressing a cotton ball and the patient feels itchiness, comfort or pleasure under pressing, it usually indicates that the shen in this point is in a deficient state. If the practitioner feels firmness or a nodule when pressing, and the patient feels pain or uneasy, it usually indicates that the shen in this point is in an excess state.
The needling technique to be employed on a selected point should be based on the state of shen of this point.
4.2.2 Step 2: Tonifying deficiency and reducing excess
It is stated in Chapter 3 of the Ling Shu that an outstanding practitioner guards the shen by tonifying insufficiency and reducing excess.4 It is essential to apply tonification needling technique for deficiency and reduction needling technique for excess to restore the normal state of shen in each and all selected points in a treatment. There are many acupuncture needling techniques for tonification and reduction. Among them, the needling techniques from Nan Jing best meet the principles discussed in the Section 3.1.
The tonification and reduction needling techniques are described in question number 76 of the Nan Jing. It states that “getting qi from the wei (defensive level 卫) for tonification and getting qi from the ying (nutrient level 营) for reduction. The key is to bridge the communication between the ying (nutrient) and wei (defense).”4 This statement can be considered as the basic needling technique to restore the normal state of shen. Both tonification and reduction needling techniques can be broken down into three steps.
- 1) Tonification needling technique
- Step 1: Inserting needle into the wei (defensive) level and twisting the needle gently and subtly clockwise to obtain de qi (qi arrival).
- Step 2: Holding de qi (qi arrival) and pushing the needle to the ying (nutrient) level.
- Step 3: Releasing de qi (qi arrival) by twisting needle gently and subtly counter-clockwise.
- 2) Reduction needling technique
- Step 1: Inserting and pushing needle into the ying (nutrient) level.
- Step 2: Twisting the needle gently and subtly clockwise to obtain de qi (qi arrival).
- Step 3: Holding de qi (qi arrival) and pulling the needle back to the wei (defensive) level and releasing de qi (qi arrival) by twisting needle gently and subtly counter-clockwise.
4.3 Clinical case
4.3.1 Patient’s I.D.
Source: self-reported; reliable
4.3.2 Patient’s description
A 62-year-old man described his chief complaint as pain from his skin rashes on his abdomen, subcostal region, and back, along the 10th to 12th ribs on his right side. The pain started 3.5 months ago. He described the pain as burning, aching, sharp, and sudden like an electric shock. The pain was more severe during sleep at night.
The patient also stated that he is moody and depressed, has a poor appetite, has irregular bowel movements which were loose, watery, and sometimes unexpectedly urgent, and his sleep is disturbed by the pain.
4.3.3 History of present illness
Patient stated that he started to experience pain and skin rashes with blisters about 3.5 months prior to his first visit in my office. Through clinical findings and polymerase chain reaction (PCR) test, herpes zoster was the diagnosis given by the patient’s neurologist. On the 3rd day after the onset, patient started taking 7 days of acyclovir and 14 days of prednisone. The skin rashes and blisters had faded with the medications, but the pain remained. At the time of his first visit, the patient was taking 300 mg of gabapentin (2–3 times a day) for his pain, but he stated that his pain was scored 9 out of 10 on the Visual Analogue Scale (VAS).
4.3.4 Physical examination
On his first visit, physical examination revealed a body temperature of 36.3°C, heart rate 72 beats per minute and blood pressure 120/82 mmHg. It was observed that the patient’s rashes were not fresh, and covered his abdomen, subcostal region, and back, along the 10th to 12th ribs on his right side. The lesions on his abdomen, subcostal region, and back were very sensitive to touch, including his clothing and light palpation. Patient’s complexion was pale with a painful expression.
His tongue was pale-purple and dull in color, but the tip of his tongue was red. The tongue body was enlarged with teeth marks on both sides. The coating was white and moist. His pulse was thready, wiry, and slippery on both sides.
4.3.5 Lab and diagnostic test results
A PCR test for Varicella Zoaster Virus (VZV) was performed 3.5 months ago. It was positive.
- 1) Integrative diagnosis: The diagnosis of his condition was postherpetic neuralgia (PHN). The diagnosis of PHN is determined mainly by clinical symptoms, physical exams, and a positive VZV PCR result. Based on the patient’s presenting symptoms and signs along with the characteristics of the tongue and pulse, the TCM syndrome differentiation for the patient’s condition was qi and blood stagnation with disharmony of the liver and spleen and disorders of the hun and po.
- 2) Treatment plan: The treatment principle was to regulate the liver, strengthen the spleen, activate the qi and blood and regulate the hun and po to relieve pain.
Taodao (陶道 DU 13), Pishu (脾俞 BL 20), Pohu (魄户 BL 42), Hunmen (魂门 BL 47), Taichong (太冲 LV 3), and Zhigou (支沟 SJ 6) were the major point selections for treatment. Filiform needles were used on all points. Nan Jing–based tonification and reduction needling techniques discussed above were employed based on the state of shen in each point. He received acupuncture treatments twice a week for 3 weeks, then once a week for 5 weeks.
After the 3rd treatment, his pain had decreased from 9 to 4 to 5 on the VAS. The patient’s primary care doctor approved reducing 300 mg gabapentin from 2 to 3 times a day to once a day before bedtime. On his 5th visit, patient reported that the pain level was 2 to 3 on VAS. He had stopped taking gabapentin after consulting with his primary care physician. On his 10th visit, patient reported that there was no pain on the right side of his body where the rashes were. It was observed that the skin rashes had faded although some marks remained. He reported that his sleeping, digestion, energy and mood had improved significantly. The patient was discharged after his 11th visit.
In this case, the patient’s disorders of hun and po were addressed in his TCM syndrome identification. The treatment of shen, especially through the treatment of hun and po, was emphasized in acupuncture treatment. The point selections and needling techniques also followed the principle of the treatment of shen. The result was satisfactory.
It is stated in Chapter 73 of the Ling Shu, that “it is essential not to neglect shen in order to apply (acupuncture) needles successfully.”10 We should pay more attention to the disorders of shen, hun, and po, throughout the entire course of acupuncture treatment including clinical evaluation, treatment principle, point selections, and needling techniques. While treating a patient with chronic pain, the acupuncture treatment would be more effective if the treatments of shen (hun and po) is incorporated.
This study does not contain any studies with human or animal subjects performed by the author.
Yong-Shun Bei wrote and revised this paper.
Conflicts of interest
The author declares no financial or other conflicts of interest.