The role of negative emotional granularity and interoceptive sensibility in neuropathic and nociplastic chronic pelvic pain.

Pain has been acknowledged as consisting of both emotional and sensory components. Within constructivist theories of emotion, the ability to make subtle distinctions among emotional states - known as emotional granularity (EG) - has been proposed as a downstream mechanism in chronic pain. However, its role remains empirically unexplored. In the current study, we investigated the concurrent and prospective associations between negative EG and pain intensity, and whether dispositional interoceptive sensibility (IAs) - the tendency to focus on internal sensations - moderates this relationship. Sixty-eight women with neuropathic and nociplastic chronic pelvic pain completed diary entries at each pain episode over one month. We assessed integral EG (across broad emotion families), between- and within-category EG (across and within the anger, fear, and sadness families), using multilevel models to predict concurrent and subsequent pain. Our results showed that higher integral and between-category EG were associated with lower concurrent pain among women with average-to-low IAs. Within-category EG showed no concurrent relationship with pain intensity. Prospectively, fear-specific EG in high-IAs participants was associated with heightened subsequent pain. Overall, our findings suggest that the association between EG and pain intensity is conditional on EG type, temporal frame, and interoceptive focus, thus highlighting its potential role in pain chronification.