Figure 5.

Patients with CBP are characterized by reduced vmPFC responses to prediction error and increased responses to a discriminative stimulus

(A–C) (Left) BOLD responses to (A) positive monetary reward prediction error, (B) the discriminative stimulus for monetary rewards, and (C) functional connectivity between left NAc and vmPFC during positive monetary reward prediction error are depicted as p maps and were calculated using non-parametric two-sample t tests (CBP > HC shown in red and yellow, CBP < HC shown in blue and light blue) within a mask of vmPFC and NAc, with bootstrapping, using 5,000 permutations (all reward-learning contrasts that dissociated HC and CBP in vmPFC and NAc are shown).

(Right) No significant correlations were found between pain severity in patients with CBP and the BOLD response in predefined masks of the vmPFC and NAc for the respective contrast. Outliers are depicted as empty circles and imputed values as triangles. See Tables S9 and S10 for all other associations between reward-learning contrasts and pain severity. vmPFC, ventromedial prefrontal cortex; lNAc, left nucleus accumbens; DS, discriminative stimulus; PPE, positive prediction error for monetary rewards.