Increased insula response to interoceptive attention following mindfulness training is associated with increased body trusting among patients with depression.

Interoceptive dysfunction is often present in anxiety and depression. We investigated the effects of an 8-week intervention, Mindfulness Training for Primary Care (MTPC), on brain mechanisms of interoceptive attention among patients with anxiety and/or depression. We hypothesized that fMRI brain response to interoception in the insula, a region known for interoceptive processing, would increase following the MTPC intervention, and that such increases would be associated with post-intervention changes in self-reported measures of interoceptive awareness. Adults (n = 28) with anxiety and/or depression completed baseline and post-intervention fMRI visits, including a task in which they alternated between focusing on their heartbeat (interoception (INT)) and a control visual attention task (exteroception (EXT)). Following MTPC, we observed increased evoked fMRI response (relative to baseline) in left anterior insula during the INT-EXT task contrast (z > 3.1, p < 0.001 corrected). In patients with moderate-to-severe depression as defined by the Patient Reported Outcomes Measurement Information System (PROMIS), increased post-intervention insula response was associated with increased Body Trusting, a subscale of the Multidimensional Assessment of Interoceptive Awareness (z > 3.1, p = 0.007 corrected). This study demonstrates that patients with mood disorders may respond differentially to mindfulness-based treatment depending on depression severity, and that among those who are more depressed, increased trusting in one's own body sensations and experiencing the body as a safe place to attend to may be necessary components of positive responses to mindfulness-based interventions.