Somatosensory false feedback biases emotional ratings through interoceptive embodiment.
Joel Patchitt, Sarah Garfinkel, William H Strawson, Mark Miller, Manos Tsakiris, Andy Clark, Hugo D Critchley
Scientific reports April 3, 2025 Peer reviewed DOI: 10.1038/s41598-025-94971-6 via PubMed
Summary
False feedback through pulsatile somatosensory stimulation, at rates either faster or slower than a person's actual heart rate, can bias how emotionally intense facial expressions are perceived. The effect increased over each 20-second stimulation block. Neuroimaging revealed that this stimulation engages brain regions involved in affective touch, embodiment, and reflex suppression, with the right insula and socio-emotional processing centers activated when contrasting faster versus slower stimulation. The findings suggest that bodily sensations are progressively embodied as perceived arousal, shaping emotional judgments through integration of prior expectations and prediction-error signals.
Study at a glance
| Design | observational cohort |
|---|---|
| Key finding | Pulsatile somatosensory false feedback at rates higher or lower than heart rate biases emotional intensity ratings of facial expressions, increasing over time, and engages right insula and socio-emotional processing regions. |
Abstract
Mismatches between perceived and veridical physiological signals during false feedback (FFB) can bias emotional judgements. Paradigms using auditory FFB suggest perceived changes in heart rate (HR) increase ratings of emotional intensity irrespective of feedback type (increased or decreased HR), implicating right anterior insula as a mismatch comparator between exteroceptive and interoceptive information. However, few paradigms have examined effects of somatosensory FFB. Participants rated the emotional intensity of randomized facial expressions while they received 20 s blocks of pulsatile somatosensory stimulation at rates higher than HR, lower than HR, equivalent to HR, or no stimulation during a functional magnetic resonance neuroimaging scan. FFB exerted a bidirectional effect on reported intensity ratings of the emotional faces, increasing over the course of each 20 s stimulation block. Neuroimaging showed FFB engaging regions indicative of affective touch processing, embodiment, and reflex suppression. Contrasting higher vs. lower HR FFB revealed engagement of right insula and centres supporting socio-emotional processing. Results indicate that exposure to pulsatile somatosensory stimulation can influence emotional judgements though its progressive embodiment as a perceived interoceptive arousal state, biasing how affective salience is ascribed to external stimuli. Results are consistent with multimodal integration of priors and prediction-error signalling in shaping perceptual judgments.