Embodied Interoception Questionnaire (Intero-10): development, validation, and application in people with chronic pain

Embodied interoception refers to the perception of the body state and is a multidimensional cognitive process. It is proposed that the experience of pain also feeds interoceptive networks with information from the state of the body, and the subjective experience of pain would be influenced by an individual's trait embodied interoceptive profile. Here we developed and validated the Intero-10, a questionnaire designed to specifically evaluate embodied interoception based on trait interoceptive channels. Healthy adults (n=381) and people with neuropathic pain (n=86) were enrolled. The relationship between trait and state interoceptive responses was examined during experimentally evoked interoceptive psychophysics tasks, which were specific for each interoceptive channel. During these tests, embodied interoceptive state scores only correlated with trait ones for unpleasantness (P<0.05), but not for intensity rating, suggesting that the predicted negative valence of lived experience provided lower prediction errors than intensity estimations. The Intero-10 final version included embodied interoceptive perception intensity (heartbeat, heat, itching, dyspnea, sleep, muscle fatigue, and anguish) and unpleasantness (heartbeat, dyspnea, and nausea) categories. Intero-10 demonstrated adequate content validity, good internal consistency (=0.81), good reliability (>0.75), and a single-factor structure. Patients with neuropathic pain filled in the Intero-10 alongside traditional pain, mood, sleep, and quality of life assessments. Embodied interoception scores correlated with mood, and quality of life, and partially mediated the correlation between pain interference and quality of life (=-0.0093). The specific assessment of embodied interoceptive channels may broaden our current assessment of people with chronic pain and of those at risk to develop it.