Teaching a new dog old tricks: bringing rigor, grounding, and specificity to psychedelic neuropsychopharmacology
Neuropsychopharmacology August 6, 2024 Nathan H. Heller, Frederick S. Barrett 4 citations
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Nathan H. Heller
Johns Hopkins University
2 papers in the library · 7 citations · publishing 2024-2025
Papers
Visual Hallucinations in Serotonergic Psychedelics and Lewy Body Diseases
Schizophrenia Bulletin April 17, 2025 Nathan H. Heller, Frederick S. Barrett, Tobias Buchborn et al. 3 citations
Visual hallucinations in Lewy body diseases (Parkinson's disease and dementia with Lewy bodies) and those induced by serotonergic psychedelics (psilocybin, mescaline) share overlapping phenomenology and neural mechanisms, despite different underlying causes. Both conditions produce visual aberrations from minor distortions to complex hallucinations, including illusory motion and entity encounters. Neuroimaging shows a common pattern of overactive associative cortex and underactive sensory cortex. Serotonin 2A receptor modulation is involved in both: psychedelics act through 5-HT2A and 5-HT1A receptors, while in Lewy body diseases, 5-HT2A receptor upregulation correlates with increased hallucinations, and blocking it with pimavanserin reduces them. Shared cortical signatures include reduced visual evoked responses and shifts toward visual excitation.