3 Truths of Pain

Pain is multifaceted, but there are some essential aspects to this signal we will all experience, and better understanding of this phenomenon can help us manage our pain.

An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.¹

— IASP revised definition of pain, 2020.

First Truth

Pain is subjective. The phenomenon of pain, defined above, is by nature an individual experience. Pain is processed differently by each individual, and the experience of pain is affected by each person’s own biological, social, and psychological factors.

Biological factors which influence pain include:

1. Genetics
2. Hormones
3. Sex
4. Age
5. Medication Use
6. Tissue Quality

Psychological factors influencing pain may include:

1. Expectations
2. Stress
3. Mood
4. Coping Skill
5. Beliefs

Social aspects of the pain experience often include:

1. Support Networks
2. Family Dynamics
3. Culture/Tradition
4. Poverty
5. Occupation
6. Relationships

All of the above contribute to and affect pain signaling differently in each individual, no two human beings experience pain exactly the same.

Second Truth

Pain is adaptive. If pain did not serve a function, it would not exist as a strategy our bodies employ to alter our behavior. In the course of human evolution, pain has been selected as a useful tool for the continuation of our species. Without pain we would quickly succumb to trauma, disease, and activities which offer high risk with little or no reward.

The advantages of feeling pain are that action can be taken to stop or ameliorate damage and future risk of damage can be reduced because pain acts as a reinforcer in learning to avoid potential damage.²

Human actions initiated by pain since prehistory:

1. Recoil from noxious stimuli
2. Inhibit activity which would delay healing or recovery from injury
3. Learning
4. Reduce chances of starvation and exposure to extreme cold or heat
5. Avoid tissue damage

As you can see, these adaptive aspects of pain which were selected for through millions of years of evolution, can still provide valuable feedback even in modern times.

Third Truth

Pain is processed in our brains, but the brain does not feel pain. That tidbit is small comfort to my readers who are headache sufferers. What’s the deal with headaches then? Pain is initiated by nociceptors in the peripheral tissues of our bodies such as connective tissue, skin, muscle tissue, the dura which encase our central nervous systems, and some organs. These structures are all equipped with special cells called nociceptors, which pick up stimulation and transmit it to our brains where it is processed into pain.

In the case of migraine, the initiating nociceptors may be located in the meninges surrounding the brain which become hyper-excitable to stimulation including sound, light, taste, smell, and other forms of peripheral stimulation³. So while the brain itself is not the source of the initiating nociceptors, brain adjacent tissues can and do lead to sometimes excruciating pain in what feels like our brains.

The fact pain is processed in our brain but not felt there can be an advantage as well. This means some brain surgery can be performed without causing the patient pain.

Final Thoughts

Pain is complex, due to the variety and interplay of biological, social, and psychological factors which contribute to pain signaling in our brains. Interventions focused on alleviating pain are often too heavily weighted towards the biological aspect of the pain experience.

Medications, various herbal remedies, hot or cold therapy, physical therapy, over the counter analgesics, chiropractic care, surgery…all of these interventions attempt to address the biological aspect of pain, and they are often successful or there wouldn’t be a market for them.

Improving education, setting realistic expectations around pain, creating robust social systems and safety nets, reducing poverty, increasing access to physical and mental health care services…these are all actions which may seem disassociated from the human experience of pain, but if the objective is to reduce pain, the social and psychological aspects of pain must be addressed with far more resources than they are currently allotted.

References:

1. Raja, Srinivasa N.a,*; Carr, Daniel B.b; Cohen, Miltonc; Finnerup, Nanna B.d,e; Flor, Hertaf; Gibson, Stepheng; Keefe, Francis J.h; Mogil, Jeffrey S.i; Ringkamp, Matthiasj; Sluka, Kathleen A.k; Song, Xue-Junl; Stevens, Bonniem; Sullivan, Mark D.n; Tutelman, Perri R.o; Ushida, Takahirop; Vader, Kyleq The revised International Association for the Study of Pain definition of pain: concepts, challenges, and compromises, PAIN: September 2020 — Volume 161 — Issue 9 — p 1976–1982 doi: 10.1097/j.pain.0000000000001939
2. Broom, Donald. (2001). Evolution of pain. Vlaams Diergeneeskundig Tijdschrift. 70. 17–21.
3. Dodick, D.W. (2018), A Phase-by-Phase Review of Migraine Pathophysiology. Headache: The Journal of Head and Face Pain, 58: 4–16. https://doi.org/10.1111/head.13300