Interoceptive threat in adolescents with chronic pain: Evidence for fear responses during anticipation and provocation of internal bodily sensations.

As fear of interoceptive sensations may play a pivotal role in chronic pain persistence and its co-occurrence with emotional disorders, a thorough understanding of these fear-related processes is essential. We investigated whether anticipation and provocation of (non-painful) interoceptive sensations proximal to the main pain site elicit a multimodal fear response in adolescents with chronic pain compared to distal sensations or a control task. Startle response, skin conductance level (SCL), heart rate (HR), self-reported fear and avoidance were assessed. Adolescents (11-18 years) with chronic abdominal pain (CAP, n=31), chronic headache (CH, n=42) and a control group (n=27) anticipated and performed three muscle tension tasks: tighten stomach (proximal for CAP), tighten neck (proximal for CH), and clench fists (control task). Anticipation of proximal sensations elicited increased self-reported fear compared to the control task in both pain groups, while physiological parameters remained unchanged. Provocation of proximal sensations elicited increased startle response, mean HR, HR reactivity and self-reports in CAP. CH exhibited startle potentiation and increased SCL during provocation of distal (compared to proximal) sensations, while self-reports were increased following proximal sensations compared to control task. The control group exhibited a similar pattern during both, the tighten stomach and neck task compared to control task, with self-reports being less pronounced compared to CAP and CH. The results provide preliminary support for fear responses to interoceptive sensations in adolescents with chronic pain. Future research is needed to deepen our understanding of disorder-specific response patterns, and to investigate how these findings can be translated into treatment. PERSPECTIVE: This article shows that anticipation and provocation of (non-painful) interoceptive sensations elicits fear responses in adolescents with chronic pain. The results could help to design therapy interventions for adolescents with chronic pain addressing these fear responses, such as interoceptive exposure.