Papers of the Week

Our sensory impressions of pain are generally thought to represent the noxious properties of an agent but can be influenced by the predicted level of threat. Predictions can be sourced from higher-order cognitive processes such as schemas, but the extent to which schemas can influence pain perception relative to bottom-up sensory inputs and the underlying neural underpinnings of such phenomenon are unclear. Here we investigate how threat predictions generated from learning a cognitive schema leads to inaccurate sensory impressions of the pain stimulus. Healthy men and women participants first detected a linear association between cue-values and stimulus intensity and rated pain to reflect the linear schema when compared with un-cued heat stimuli. The effect of bias on pain ratings was reduced when prediction errors increased, but pain perception was only partially updated when measured against stepped increases in prediction errors. Cognitive, striatal, and sensory regions graded their responses to changes in predicted threat despite of the prediction errors (p<0.05, corrected). Individuals with more catastrophic thinking about pain and with low mindfulness were significantly more reliant on the schema than on the sensory evidence from the pain stimulus. These behavioral differences mapped to variability in responses of the striatum and ventral medial prefrontal cortex. Thus, this study demonstrates a significant role of higher-order schemas on pain perception and indicates that pain perception is biased more towards predictions and less towards nociceptive inputs in individuals who report less mindfulness and more fear of pain.Significance statement: This study demonstrates that threat predictions generated from cognitive schemas continue to influence pain perception despite of increasing prediction errors arising in pain pathways. Individuals first formed a cognitive schema of linearity in the relationship between the cued threat value and the stimulus intensity. Subsequently, the linearity was reduced gradually, and participants partially updated their evaluations of pain in relation with the stepped increases in prediction errors. Individuals who continued to rate pain based more on the predicted threat than on changes in nociceptive inputs reported high pain catastrophizing and less mindful-awareness scores. These two affects mapped to activity in the ventral and dorsal striatum respectively. These findings direct us to a significant role of top-down processes in pain perception.