Symptom threshold
The point at which a bodily state stops being just a state and starts being a symptom — and the claim that its height is a movable individual difference, not a fixed property of the sensation.
A tired ache, a gut flutter, a headache: each can sit unremarked as an ordinary bodily state, or be recruited into an “ill-health” frame and reported as a symptom. The threshold idea says the difference is not (only) in the sensation’s intensity but in a criterion the person applies, and that criterion is set by who is attending, in what mood, expecting what, and looking for what meaning. Carter & Ogden (2023) make this explicit — it is the “transcending theme” running through their four themes of how bodily states are experienced, attended to, become symptoms, and are reified — and note it is “rarely explicit” elsewhere, even though models of symptom perception (Leventhal’s Self-Regulatory Model, somatosensory amplification) all quietly assume it.
Staged, not a single cut-point
The distinctive claim is that there is a series of thresholds, so a state can pass one and not the next:
- pass the attentional threshold (noticed) but not the meaning/reifying threshold → noticed but not symptomatised (“I just notice and let it pass like you would with a thought”);
- pass attention and meaning → recruited into an illness frame and reported.
This is what lets the model hold both “I am hyper-aware of my body” and “but most of what I feel never becomes a symptom” in the same person.
What moves the threshold
Lowered (easier to become a symptom): habitual body-focus; negative affect, especially anxiety and depression; expecting a symptom to recur; and attributing a new sensation to an existing diagnosis (reading “any niggle” as a Crohn’s flare). Raised (harder): deliberately ignoring or normalising states; treating bodily activity as the body “doing something it needs to do”; and simply not having a chronic condition that primes expectation.
Note the direction of the affect and expectation effects is the same as anxiety-sensitivity and schema-guided-symptom-perception predict, and the same as the cardiac panic literature (ehlers-1993-interoception-panic) finds: threat and body-focus pull the criterion down.
Why it is interoceptive inference in folk vocabulary
The mapping is close enough to be worth stating plainly:
| threshold language | predictive-coding / schema language |
|---|---|
| threshold lowered by expectation / reading a sensation as one’s diagnosis | strong prior dominating the percept |
| threshold lowered by negative affect and attention | interoceptive precision up-weighted; anxiety schema activated |
| state noticed but not symptomatised | prediction error registered but unattributed by a higher model |
| finding meaning / attributing medical cause | model selection over the sensation |
| threshold raised by normalising | habituation; low pathology prior |
The point of recording it is the same as schema-guided-symptom-perception: this is a non-predictive-coding tradition arriving at the predictive-coding picture, here from qualitative interviews rather than clinical theory. The convergence is mild evidence the picture is not a vocabulary artefact — but the threshold account, like the schema account, names a criterion rather than specifying what sets it, where the inference account at least offers a quantity (precision). It is the more intuitive statement and the less mechanistic one.
What the wiki should not overclaim
The concept is recorded for its bridging role, not as an established mechanism. Carter & Ogden describe thresholds; they never measure one — no accuracy task, no physiology, no operationalisation, N = 12 self-selected. Medical anthropology (Halowski 2006; Hay 2008) has treated symptom thresholds as culturally defined durations/vulnerability-matches that must be exceeded before a sensation is socially legitimised as a symptom, which is a richer version of the same idea; that literature is not in raw/. So “symptom threshold” is best held as a useful organising hypothesis — a way of saying that the sensation-to-symptom transition is a moved criterion, not a fixed cut — that the wiki’s predictive-coding sources (interoceptive-inference, schema-guided-symptom-perception) supply the candidate mechanism for.