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.
The text critically examines the use of MDMA in therapeutic contexts, arguing that the current enthusiasm for MDMA-assisted therapy may overlook significant risks and methodological shortcomings. It questions the robustness of evidence supporting its efficacy for conditions like PTSD, highlighting issues such as small sample sizes, lack of long-term safety data, and potential for adverse effects. The author suggests that a sober, evidence-based evaluation is necessary before embracing MDMA as a treatment, emphasizing the need for rigorous research and caution against premature adoption.