Neuroplasticity and psilocybin: what the research actually says vs. what people claim

What the research actually shows: psilocybin promotes synaptogenesis (new synapse formation) and dendritic spine growth in the prefrontal cortex. These structural changes have been measured in preclinical models. Human imaging data shows altered connectivity patterns that persist for weeks. This is real, though the clinical significance is still being worked out.

The overclaim: 'psilocybin rewires the brain.' Neuroplasticity is a normal ongoing process. Psilocybin appears to enhance or accelerate certain aspects of it, particularly in windows of learning and therapeutic engagement. But the 'rewiring' metaphor implies more structural permanence than the evidence supports.

The honest summary: we have good mechanistic evidence for acute effects on neural connectivity, some evidence for lasting structural changes in preclinical models, and emerging clinical data suggesting these changes correlate with therapeutic outcomes. The chain of causation is plausible but not fully established in humans.