Psychosis may stem from altered predictive coding in the brain, where prior beliefs are combined with sensory signals to interpret the world. The canonical account suggests that weakened prior beliefs relative to sensory data lead to maladaptive inferences. However, evidence is mixed: some studies find weakened priors, others stronger priors. Hallucinations and delusions may involve distinct predictive coding alterations. Challenges include non-uniform deficits across sensory modalities, hierarchical processing where lower and higher levels interact non-linearly, and the role of active inference—anticipating how actions affect sensations. Considering these complexities could reconcile conflicting findings and yield a more comprehensive framework for psychosis.
Mindfulness practice groups are an acceptable therapeutic intervention for patients in psychiatric rehabilitation, most of whom have treatment-resistant psychosis. Around two-thirds of in-patients attended at least one group, and about a third attended regularly. No measurable impact on well-being was detected using the Warwick-Edinburgh well-being scale. Qualitative interviews indicated benefits for individuals and potential to improve the therapeutic culture on wards. The findings suggest that further research into the effectiveness of mindfulness for treatment-resistant psychosis is warranted.