Figure 5.

Simulation of ten sessions of exposure therapy in the nullspace of marginal $p(pain)=0.7$, with ambiguous and imprecise likelihoods (A) and precise and accurate likelihoods (B). On the $X$-axis are the time steps, on the $Y$-axis the marginal probabilities of pain, and on the $Z$-axis the learning trials per time step. The combination of null space derived transition probabilities and an imprecise and ambiguous likelihood model ($p(\text{noxious}\mid \text{pain})=0.6$, $p(\text{harmless}\mid \text{pain})=0.4$, $p(\text{noxious}\mid \overline{\text{pain}})=0.6$, $p(\text{harmless}\mid \overline{\text{pain}})=0.4$) renders the repeated presentation of innocuous sensory information rather inefficient: inferred probabilities of pain remain within the range of the predefined marginal. When the likelihood model is precise and unambiguous ($p(\text{noxious}\mid \text{pain})=0.8$, $p(\text{harmless}\mid \text{pain})=0.2$, $p(\text{noxious}\mid \overline{\text{pain}})=0.1$, $p(\text{harmless}\mid \overline{\text{pain}})=0.9$), however, the presentation of harmless sensory information is more efficient in reducing the inferred probability of pain.