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Epiphyte City
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Epiphyte City
By: Drs. Milton Cohen and John Quintner
Conflation, confusion, confounding
In Pain Med to be found abounding
Misnomers and myths
And logical slips
No wonder the ship is a-foundering
Painlosophy exists to help in explaining, demystifying and clarifying concepts in pain science and medicine that may be confusing. In this post, we will argue that a fundamental cause of such confusion is the fallacy of conflation.
“Conflation”, from the Latin verb conflare, “to blow together” or “to fuse”, means the merging or blending together of two or more distinct ideas, texts or sets of information into one, which then leads to treating them as being equivalent to each other.
Conflation needs to be distinguished from confusion and confounding. Confuse is the most general term and primarily means to perplex or bewilder someone, making something hard to understand. It can also mean to mix up two or more things, either deliberately or by mistake (e.g., “I always confuse my left and right”). Confound can also mean “to mix up,” but more commonly to cause surprise or bewilderment, often in a way that proves something wrong or defeats a plan or hope (e.g., “The sudden increase in demand confounded the sales team”).
Although he did not use the term conflation, the British philosopher John Locke (1632-1704) clearly recognised the problem:
Some of our ideas have a natural correspondence and connexion one with another… Besides this, there is another connexion of ideas wholly owing to chance or custom: ideas that in themselves are not at all of kin, come to be so united in some men’s minds that it is very hard to separate them; they always keep in company, and the one no sooner at any time comes into the understanding, but its associate appears with it; and if they are more than two which are thus united, the whole gang, always inseparable, show themselves together.
In his own essay on Locke’s, contemporary philosopher Jonathan Bennett (1930-2024), concluded:
“Conflations, I now see, can be hard to avoid. A dense network of isomorphisms between two related areas of our conceptual scheme can create a magnetic field, pulling the philosopher across from one towards the other so that he ends up unwittingly thinking about both at once” [Bennett 1996:6]
In other words, concepts that are basically different but bear some resemblance to each other act like magnets to entice the thinker to consider them as one and the same.
Here we will present two sets of conflation that continue to exert powerful (and, in our opinion, harmful) influence in the pain world:
A. Pain and nociception (the fundamental conflation fallacy in modern pain science, often termed Pain Neuroscience Education [Moseley 2013])
B. “primary” pain and “nociplastic” pain and “nociplastic pain conditions”.
A. CONFLATION OF PAIN AND NOCICEPTION
In the Note that accompanied the IASP’s first iteration of a pragmatic definition of pain in 1979, it is stated:
“Activity induced in the nociceptor and nociceptive pathways by a noxious stimulus is not pain…”
Although it was not made explicit at that time, the phrase “activity induced in the nociceptor and nociceptive pathways by a noxious stimulus” was a de facto definition of nociception. (Interestingly, nociception was not formally defined in the IASP terminology until 2005, as “the neural processing of encoding noxious stimuli”.)
So that sentence in the 1979 note can be read as:
“Nociception is not pain”.
That admonition was made again in the Notes accompanying the 2020 iteration of the IASP definition of pain:
“Pain and nociception are different phenomena. Pain cannot be inferred solely from activity in sensory neurons.”
It was also widely known that nociception (using either of the definitions above) is not always associated with a pain experience. In formal terms this is stated as, nociception is not sufficient for pain.
Enter the so-called “pain descriptors”: “nociceptive” (not formally defined until 2005); “neuropathic”(first formally defined in 1994) and the more recent “nociplastic” (defined in 2016).
- “Nociceptive pain” is defined as “pain … that is due to activation of nociceptors”. Correctly, that should be phrased as “pain associated with engagement of nociception via nociceptors”, or as “pain associated with nociceptive [engagement of] nociception”.
- “Neuropathic pain” is “pain caused by a lesion or disease of the somatosensory nervous system”. Correctly, that should be phrased as “pain associated with pathology of the somatosensory system”, or as “pain associated with neuro-pathic [engagement of] nociception”. (The hyphen in “neuro-pathic” is deliberate here, to emphasise that “a lesion or disease of the somatosensory nervous system” is a neuro-pathy.)
In both these cases, the “descriptor” is in fact of nociception, not of a pain experience. This is a classic case of conflation.
The use of “due to” and “caused by” respectively in these definitions exposes two other errors. Firstly, that usage goes further than the “associated with” that occurs in the current definition of pain itself; secondly, it ignores that nociception is not sufficient for pain. Both can be solved by recasting the definition of pain as “… an experience contingent on nociception” [Cohen, Weisman & Quintner 2026].
- “Nociplastic pain” is explicit in this respect: “pain that arises from altered nociception [and … is not “nociceptive” or “neuropathic]”, implying that a different pathway(s) of [engagement of] nociception is involved.
As Bennett suggested above, this conflation may have been difficult to avoid. When confronted with the slippery concept of pain as an experience, which is not a material thing, it would be attractive to merge it with its cousin nociception, which is a material thing, thus justifying the use of an adjective that applies only to nociception.
Even though it may have been unavoidable, now that the conflation of pain and nociception has been identified, it should not be perpetuated. Why? Because the conflation of distinct entities into one causes people to be confused and their expectations to be confounded. This can lead to flawed arguments, and hinder clear analysis and decision making.
B. CONFLATION OF “PRIMARY” PAIN AND “NOCIPLASTIC” PAIN AND “NOCIPLASTIC PAIN CONDITIONS”
(i) Conflation of primary and nociplastic pain
“As the construct of nociplastic pain has solidified, the preferred terms are now … the new International Classification of Diseases (ICD-11) term, primary pain” [Clauw 2024].
“Primary pain” in ICD-11 is a taxonomic concept, to be applied only when no other pain condition is able to be identified. ICD-11 – and therefore “primary” pain – is agnostic to mechanism of nociception (and indeed preceded the construct of “nociplastic pain”). “Primary” pain is not a diagnosis, just as pain itself is not a diagnosis.
By contrast “nociplastic” is, strictly, a descriptor of a mechanism of engagement of nociception, not of a pain experience. We have to accept that, although they are misnomers, “nociceptive pain”, “neuropathic pain” and “nociplastic pain” are not going to go away for a while. However, the IASP terminology states that none of these “descriptors” is a diagnosis.
Furthermore, once clinical features for “nociplastic pain” – strictly nociplastic engagement of nociception – have been validated, conditions featuring that will move out of the “primary” into the “secondary” category in ICD-11.
We can only apologise for mouthfuls such as “nociplastic engagement of nociception” but that is where we are now.
(ii) Conflation of nociplastic pain and conditions that are claimed to feature this process
“The severity of nociplastic pain can be measured using the Fibromyalgia Survey Criteria” [Kaplan et al. 2024].
Fibromyalgia comprises a cluster of subjective clinical features that by definition are not necessarily pathogenetically related to one another, let alone to nociception. “Nociplastic” pain (itself an example of conflation of pain and nociception) may be the most prominent feature of fibromyalgia but it does not denote a symptom cluster.
(iii) Conflation of nociplastic pain and central sensitisation of nociception
“CS [central sensitization] is not part of the definition of nociplastic pain; however, signs of sensitization are generally present in nociplastic pain conditions … Moreover, sensitization is the major underlying mechanism of nociplastic pain … Hence, patients whose clinical picture is dominated by CS are labelled as having nociplastic pain” [Nijs et al. 2021].
In current usage, “nociplastic” is used to describe a clinical pain experience, although that is an error as we have shown. A clinical pain phenomenon is not the same as a neurophysio-logical one, such as central sensitisation of nociception (CSN). CSN is demonstrable only experimentally in animals; it can only be inferred in humans. It may well turn out that CSN is a mechanism of engagement of nociception that is distinct from both “nociceptive” and “neuropathic” and justifies the label “nociplastic” but that has not yet been shown.
Hopefully by that time “nociplastic” will have been detached from “pain” and attached to “nociception”. Until then the two terms should not be conflated.
SUMMING UP
Our intention has been to increase readers’ vigilance about the fallacy of conflation, in response to much evident confusion in the literature regarding some basic words and concepts used in pain science and medicine.
The pioneer voice in the IASP definition of pain process, the late Harold Merskey, warned against confusing mechanisms of pain with the phenomenal experience by “mixing physiological conceptions with psychological ones.” [Merskey 1991:157].
The major conflation in this field is that of pain, which is an experience, with nociception, which is the signalling to an organism that tissue damage has occurred. The IASP terminology states unequivocally that pain and nociception are different phenomena. They are of course not unrelated, as nociception is necessary but not sufficient for pain.
This conflation has been unwittingly abetted by the well-intentioned introduction of the three so-called “pain descriptors” – “nociceptive”, neuropathic” and “nociplastic” – which in fact do not describe a pain experience but rather a mechanism of engagement of nociception.
This is not at all to argue that those adjectives should be abandoned but rather that they be detached from “pain” and attached to “nociception”. This logical step however has major implications for labelling of clinical pain conditions, as depicted in the second cartoon above.
References
Bennett J. Ideas and qualities in Locke’s essay. Hist Philos Q 1996;13:73-88.
Cohen ML, Weisman A, Quintner JL. Pain is not a “thing”: how that error affects language and logic in Pain Medicine. J Pain 2022;23(8):1283-1293. doi: https://doi.org/10.1016/j.jpain.2022.03.235.
Cohen ML, Weisman A, Quintner JL. Paradoxes weaken the International association for the Study of Pain definition of pain. Korean J Pain 2026;39:1-8. Doi.: htpps://doi.org/10.3344/kjp.25268
Merskey H. The definition of pain. Eur Psychiatry 1991;6:153-159.
Epiphyte City
In May the German National Library of Medicine announced its plan to develop an open, sustainable, and sovereign alternative to PubMed, the free online biomedical database housed in the National Library of Medicine at the National Institutes of Health.
The announcement of this alternative was greeted with interest and support, particularly from those who see the need for digital sovereignty and infrastructural resilience. The project, ZB MED, has been gathering steam, pulling in European partners, publishers, and funders to turn the vision into reality. Its search engine LIVIVO is now available for literature and information in the health field.
Epiphyte City
A cohort of 168 Palestinian doctors have received their advanced medical certifications in Gaza amid the rubble of what was once the Palestinian territory’s largest hospital.
The graduation took place in front of the destroyed facade of the al-Shifa Medical Complex in Gaza City on Thursday. It was a symbolic act of resilience as the doctors, calling themselves the “Humanity Cohort”, completed their Palestinian Board certifications under extraordinary circumstances after two years of Israel’s war.
list of 3 itemsend of listThe graduates had studied and sat for examinations while working nonstop inside Gaza’s hospitals during two years of starvation, displacement and genocide. Some were also injured, arrested or had family members killed.
Gaza Health Ministry official Youssef Abu al-Reish described the ceremony as graduation from “the womb of suffering, under bombardment, among rubble and rivers of blood”.
Dr Mohammed Abu Salmiya, al-Shifa’s medical director, said Israel sought to destroy Palestine’s human capital throughout its attacks on healthcare facilities, “but it failed in that”.
Dr Ahmed Basil, one of the graduates, said earning advanced degrees in the most difficult of times inside a destroyed building sent a message that Palestinians love life and remain committed to scientific advancement.
The ceremony included empty chairs displaying photographs of healthcare workers killed during the war.
Palestinian doctors who lost their lives in Israeli attacks were commemorated during the graduation ceremony held at al-Shifa Hospital [Saeed M M T Jaras/Anadolu Agency]‘An empty shell with human graves’
Al-Shifa Medical Complex has been repeatedly targeted since Israel’s genocidal war began in October 2023.
The facility was invaded twice, first in November 2023, when Abu Salmiya himself was arrested and detained for seven months, and again in March 2024, when the complex suffered catastrophic destruction.
A World Health Organization assessment conducted in early April 2024 found the hospital had been reduced to what WHO Director-General Tedros Adhanom Ghebreyesus described as “an empty shell with human graves”.
The hospital has since been partially renovated but still largely lies in ruins.
The destruction of al-Shifa exemplifies a broader systematic campaign against Gaza’s healthcare system.
Of the territory’s 36 hospitals, only 18 remain even partially functional as of mid-December, with all but three field hospitals operating under severe limitations. More than 18,500 critically ill patients, including 4,000 children, require medical evacuation that remains largely inaccessible.
Hospitals attacked, medics killed
The WHO Health Cluster has documented 825 attacks on healthcare facilities since October 2023. These attacks have killed 985 people and injured approximately 2,000 others.
According to the Palestinian Ministry of Health, 1,722 healthcare workers have been killed in Israeli strikes over the past two years. An additional 306 individuals have been detained over the course of the war, many of whom have since been released, according to the WHO Health Cluster.
At least five healthcare workers have died while in detention, with other released detainees, and the corpses of people returned showing signs of torture and abuse.
The UN Human Rights Office has identified a consistent pattern in Israeli operations against hospitals. Initial air strikes and shelling, followed by ground troop sieges that prevent access, then raids employing heavy machinery, including tanks and bulldozers, mass detentions of medical staff and patients, forced evacuations, and finally withdrawal, leaving facilities non-functional.
Palestinian human rights organisation Al-Haq has documented what it characterises as the “systematic destruction” of Gaza’s healthcare system as a genocidal pattern.
According to the Gaza Ministry of Health, 70,942 Palestinians have been killed and 171,195 injured since 7 October 2023. Since a ceasefire was announced this October, 406 people have been killed and 1,118 injured, with the ministry noting that violations continue. An additional 653 bodies have been recovered from under rubble during this period.
Epiphyte City
For a few days, I feared the worst: a Christmas without Ibérico ham. In the run up to the holiday, Spain, my country of birth, announced the first swine fever outbreak in more than 30 years. Within hours, the UK, where I live, responded with a blanket ban on all Spanish pork meat imports. Christmas isn’t Christmas for a Spanish family without a leg of jamon — think Thanksgiving without turkey. No bueno. Fortunately, I dodged the bullet: The Spain-UK restrictions have been relaxed. But many other countries, from the US to Japan, are maintaining the full prohibition.
My panic was, admittedly, a first-world problem. But it’s a timely reminder that we’re sleepwalking into the next pandemic. We fear something like another Covid-19 outbreak, but probably the next disease to hit the global economy won’t infect humans. Instead, it would be a virus that would kill a significant proportion of the domesticated animals we rely on for meat, eggs, milk and other products.
Epiphyte City
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