Dreaming arises from the same hierarchical predictive processing that governs waking cognition, but with key modifications: lack of sensory and motor input and a predominance of associative, non-rational primary process thinking. Emotional needs guide behavior via a value system generating pleasure and unpleasure, and the brain constantly updates its predictions to minimize prediction error. Repressed priors—mental events that cannot be reconsolidated despite ongoing error signals—correspond to conflictual complexes and may become accessible in symbolic form during dreams and psychedelic states. Evidence from neuroimaging supports this framework, and an ongoing trial with stroke patients who lost the ability to dream tests whether dreaming is necessary for intact sleep architecture and memory consolidation.
A literature review on psilocybin-assisted psychotherapy for mental illnesses examined peer-reviewed studies from 2017 to 2022. Nine studies covered tobacco addiction, anxiety and depression related to life-threatening cancer, and treatment-resistant depression. Rapid clinical improvement of various symptoms was observed, with the strongest evidence for treating tobacco addiction and anxiety and depression tied to life-threatening illnesses. No serious adverse events were reported. However, current studies have limitations, including small sample sizes, difficulties with blinding, and a non-representative treatment population. The results are not representative but provide indications of effective treatment and serve as a starting point for further studies.