Proof Engine Verification (DISPROVED): Critical periods of heightened cortical plasticity close permanently after early development, rendering the adult brain largely incapable of experience-dependent reorganization comparable to juvenile levels.

Automated fact-verification of the claim: "Critical periods of heightened cortical plasticity close permanently after early development, rendering the adult brain largely incapable of experience-dependent reorganization comparable to juvenile levels." Verdict: DISPROVED Key Findings 5 independent methods have been demonstrated to reopen critical periods in adult brains, across visual, auditory, and social reward systems — directly contradicting "permanent" closure. Enzymatic (ChABC), pharmacological (VPA, fluoxetine), psychedelic (psilocybin, LSD, MDMA), and genetic (A1R knockout) interventions all restore juvenile-like plasticity in adults. Evidence spans animal models AND human subjects (VPA reopens absolute pitch learning in adult humans). Adult thalamocortical plasticity "does not disappear but becomes gated" — the machinery persists, merely suppressed by molecular brakes. Files proof.py — Re-runnable Python verification script proof.md — Structured proof report proof_audit.md — Full verification audit trail proof_narrative.md — Plain-language summary proof.json — Machine-readable structured data Generated by Proof Engine v0.9.0.