Neural Systems Connecting Interoceptive Awareness and Feelings (Pollatos et al. 2007)
The sister paper to Pollatos, Kirsch & Schandry (2005) — same Munich lab, same paradigm (60 IAPS pictures, Schandry heartbeat counting, high vs low interoceptive-awareness groups, 62-channel EEG, SAM ratings) — with one design addition that is the whole reason to hold it separately: source reconstruction. Where the 2005 study had EEG with no source localization and had to import every anatomical claim from other people’s PET/fMRI, this one runs a distributed inverse (stCDR) over the P300 window and derives its own generators. The result is the wiki’s first first-hand source-level evidence that individual differences in interoceptive awareness track activation of the interoceptive cortex.
Thirty-two people counted their heartbeats, then watched 60 IAPS pictures. Good perceivers said the emotional ones were more arousing (not more or less pleasant), had larger P300s, and — on the reconstruction — showed more activation in right insula, anterior cingulate, somatosensory and prefrontal cortex, but not visual cortex.
Not a duplicate of the 2005 paper
Easy to mistake, because the abstracts read almost identically. They are distinct papers: Pollatos, Kirsch & Schandry (2005), Cognitive Brain Research 25:948-962, n = 44, no source localization; Pollatos, Gramann & Schandry (2007), Human Brain Mapping 28:9-18, n = 32, with stCDR source reconstruction and a third author (Gramann, the EEG-source methodologist) in place of Kirsch. Different sample, different journal, different DOI, different central method. The two form a matched pair rather than one study reported twice, and reading them together is the point: the 2005 paper establishes the behavioural + scalp-ERP effect and infers the anatomy; the 2007 paper reproduces the effect in a new sample and models the anatomy.
What the source reconstruction adds, and what it does not
The 2005 page ends by noting that “the anatomy is borrowed” — every structural claim there was inferred from scalp topography plus disagreeing P300-generator studies. This paper is where the Munich group tried to supply the missing step, and it half-succeeds.
The gain. Within one dataset, the P300 to emotional pictures localizes to five generators, and the interoceptive-awareness difference is carried by the four that Damasio’s (1999) model would predict — first-order insula (BA 13) and somatosensory cortices (BA 7/40), second-order anterior cingulate (BA 32/10) and prefrontal cortex (BA 6/9) — while the visual cluster (BA 18/19), a generator with no place in the feeling circuit, shows no IA effect at all. That last null is the quiet strength of the result: the group difference is not a global amplitude offset smeared across every generator, it spares the one cluster that should be spared. See somatic-marker-hypothesis for the first-order/second-order scheme this maps onto, and insular-cortex for where the right-insula reading sits in the wider evidence.
The double dissociation the paper half-notices. The four affected clusters split cleanly by content-specificity (Table I):
| structure | order | IA effect present for |
|---|---|---|
| right insula (BA 13) | first | unpleasant only |
| anterior cingulate (BA 32/10) | second | pleasant + unpleasant (not neutral) |
| somatosensory (BA 7/40) | first | all contents incl. neutral |
| prefrontal (BA 6/9) | second | all contents incl. neutral |
So the interoceptive-cortex difference (insula) is affect-gated and specifically negative, the somatosensory difference is emotion-general. The authors’ reading is reasonable: the somatosensory enhancement reflects a habitually greater attention to the body in good perceivers (present whatever is on screen), while the insula’s negative specificity fits Craig’s and Critchley’s picture of the right insula as especially engaged by aversive interoceptive states. The unpleasant-specific right-insula finding is the datum this paper contributes to insular-cortex, and it is congruent with the later, causal Berntson et al. (2010) lesion result that the insula is broadly evaluative.
What it does not add. It is still EEG-inverse anatomy over a template brain — an ill-posed, low-resolution reconstruction, not a measurement. “The right insula (BA 13)” is a centroid of a smooth current estimate from 62 scalp electrodes; the fMRI and intracranial insula evidence the wiki holds elsewhere (insular-cortex) is a different order of spatial claim. The reconstruction upgrades the 2005 paper’s borrowed anatomy to modelled anatomy, which is a genuine step, and no further.
Same dissociation, same blind spot as its sister
Everything conceptual about this paper is already carried on pollatos-2005-interoceptive-awareness-erp, and applies here unchanged:
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The arousal/valence dissociation gets a fourth independent leg. Interoceptive awareness raised arousal ratings for emotional pictures and did nothing to valence (F(1,30) = 0.20, ns) — the same split as Pollatos 2005, Dunn et al. (2010) and Ferré et al. (2024). Four methods, three labs, two decades, one result: the bodily dimension of emotion and the hedonic dimension come apart, and interoception tracks the arousal term specifically. That points at hybrid two-factor accounts over strong Jamesian ones, which makes the abstract’s Jamesian framing an overstatement of its own finding. See core-affect.
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The Dunn disagreement. This is another selected-sample study reporting an arousal main effect of interoceptive accuracy where Dunn et al. (2010) found a null in an unselected sample. The full accounting — why the samples are not commensurable, why an extreme-groups design inflates the contrast, and why this design cannot fit Dunn’s moderation model (the bodily response it turns on was never measured) — is on the 2005 page and tracked on is-more-interoceptive-awareness-better. This paper does not change that ledger; it adds a second selected-sample instance to the same side of it.
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The body was never measured. The central omission. ECG scored the counting task and was never analysed against the pictures. So the paper localizes cortical generators of a rating difference to the interoceptive cortex without ever showing that good perceivers’ bodies responded differently — the source-level anatomy makes the Jamesian story more vivid without making it more testable. Given the cardiodynamic confound, “these are people whose hearts are louder, whose cortices are more responsive, and who rate everything emotional as more arousing” fits the entire result set, source clusters included, with no perception in it.
In the wiki’s terms
A better-instrumented member of the same pre-Dunn consensus the 2005 paper represents — see olga-pollatos. Its lasting value here is narrow and real: it is the wiki’s one source that derives, first-hand and within a single dataset, the claim that interoceptive-awareness differences live in the interoceptive and evaluative cortex (insula, ACC) and not in visual cortex, with the interoceptive-cortex effect gated to aversive material. That is worth having on insular-cortex even at the EEG-inverse discount. What it does not do — and cannot, without a bodily measure — is show that the perception of the body is what drives any of it.