The role of kinesthetic and visuospatial cues in pain-induced movement avoidance

Abstract

BackgroundAvoidance of movements is an important factor in chronic pain. Previous experiments have investigated the involved learning mechanisms by pairing movements with painful stimuli but, usually, other visuospatial cues are concurrently presented during learning. Therefore, participants might primarily avoid these visuospatial rather than the movement-related cues, potentially invalidating related interpretations of pain-induced movement avoidance. Here, we separated kinesthetic from visuospatial cues to investigate their respective contribution to avoidance learning. MethodsParticipants used a hand-held robotic manipulandum and, during an acquisition phase, received painful stimuli when performing center-out movements. Pain stimuli could be avoided by choosing a curved rather than direct movement trajectories. To distinguish the contribution of kinesthetic vs. visuospatial cues we used two generalization contexts: either participants executed novel movements passing through the same location at which pain had previously been presented in the acquisition phase; or they executed the same pain-associated movements after having been reseated, so that the hand did not pass through the pain-associated location. ResultsAvoidance generalization was comparable in both contexts, and remarkably, highly correlated between them. Our findings suggest that both visuospatial and kinesthetic cues available during acquisition were associated with pain and led to avoidance. ConclusionsOur research corroborates the fear-avoidance pain model and previous studies findings that pain can become associated with movements. However, our study indicates that visuospatial cues also play a critical role. Future studies should distinguish movement-related and space-related associations in pain learning. SignificanceChronic pain is a significant health issue typically attributed to maladaptive learning of pain-movement associations and movement avoidance. We demonstrate that visual cues can play a similarly important role as movement cues in pain learning. This aspect has not previously been considered and has likely confounded previous research findings.