In May of this year a case report appeared in Frontiers in Neuroscience that traveled farther and faster than almost any piece of psychedelic science I have ever seen. A woman in her eighties with a ten-year history of Alzheimer’s disease was given five grams of psilocybin mushrooms. Roughly nineteen hours later she began speaking about her own life again, unprompted, in sentences. Over the following weeks she regained continence, dressed herself, moved more freely, and became emotionally responsive to the people around her. A month later she was given three grams more.
I understand why that story moved. I watched my father and my brother wander down the long path of dementia. It is not pretty and the toil on families is immense. Any story that carries even a shred of hope for treatment of this affliction will garner massive media attention. Did this story carry false hope? Did the hype filled headlines do a disservice?
I want to walk through what the research on psychedelics and dementia actually shows, because the distance between that headline and the evidence underneath it is considerable. The people most likely to be hurt by closing that distance prematurely are elders and the families who love them.
The case report only involved one patient. There was no neuroimaging, no polysomnography, no standardized cognitive testing before or after. The mushrooms were an Enigma strain of unknown potency, administered not in a clinic but by an association in São Paulo. During the acute phase the woman experienced suspected hyperthermia and profuse sweating, which is not a footnote but a genuine safety signal in someone in their eighties with advanced neurodegeneration. The authors are honest about all of this. They write that causality cannot be established and that the spontaneous fluctuations inherent to neurodegenerative disease cannot be excluded. Alzheimer’s disease is famously variable. Good days happen. A single good stretch, however striking, is a hypothesis, not a result.
Let’s take a look at the actual state of human trials. There is exactly one dementia-specific trial of any consequence, and it has been open at Johns Hopkins since 2019. It is a pilot study of psilocybin for depression in people with mild cognitive impairment or early-stage Alzheimer’s disease. The trial is focused on a psychiatric comorbidity (depression) and not the disease itself. It is small study and its estimated completion date has slipped more than once. As of today no results have been published. That is the entire dedicated clinical literature. One pilot trial, still in progress, aimed at mood.
The strongest human evidence in this neighborhood comes from a different disease. Last year a team at UCSF published an open label pilot of psilocybin therapy in twelve people with mild to moderate Parkinson’s disease and clinically significant depression or anxiety. Participants received ten milligrams, then twenty-five milligrams two weeks later, most of them on stable carbidopa-levodopa throughout. There were no serious adverse events. Nothing required medical intervention. Critically, there was no worsening of psychotic symptoms and no worsening of motor features, which was the central fear going in. Depression and anxiety improved within a week and held at three months. Unexpectedly, so did spatial working memory, associative learning, and cognitive flexibility, and some motor symptoms.
That trial matters more than the case report, and it is worth being clear about why. It is the first real demonstration that a full dose of a classic psychedelic can be given to people with a progressive neurodegenerative illness, on their existing medications, without the roof caving in. That is a meaningful safety precedent and it opens a door to more research. It is also twelve people, unblinded, with no control arm, in a disease that is not dementia.
The Alzheimer’s Drug Discovery Foundation’s own assessment of psilocybin as a treatment is blunt. They conclude that there is no available human research documenting benefit to patients with dementia. Perhaps the real crime here is that there was literally no significant research funded for decades due to political and media hysteria. Because of that we have more questions than answers. Research into potential treatments were delayed which the suffering continued, and the band played on.
Here is where I land. The honest near-term target is not the reversal of neurodegeneration. It is the psychological suffering that arrives with the diagnosis and stays. This is the depression, the demoralization, and the anticipatory grief that affects the individual and those that love them. That is where the one running trial is aimed, and that is a worthy place to aim. It is also, not incidentally, where the psychedelic literature is strongest, in existential distress at the end of life.
I write about elders and psychedelics. I am one. I have no interest in talking anyone out of hope, and if a well-designed randomized trial proves me too cautious I will be delighted to be wrong. But hope is not a protocol, and a single remarkable woman in São Paulo is not a treatment.
Sources
Lago M, Cerveira M, Simonet JX. Transient multidomain functional improvement in advanced Alzheimer’s disease following high-dose psilocybin-containing mushroom administration: a case report. Frontiers in Neuroscience, May 2026. https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2026.1813281/full
Psilocybin for the treatment of Alzheimer’s disease. Frontiers in Neuroscience, 2024. https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2024.1420601/full
Psilocybin therapy for mood dysfunction in Parkinson’s disease: an open-label pilot trial. Neuropsychopharmacology, 2025. https://www.nature.com/articles/s41386-025-02097-0
Johns Hopkins Center for Psychedelic and Consciousness Research, Alzheimer’s study (NCT04123314). https://www.hopkinspsychedelic.org/alzheimers-study
Alzheimer’s Drug Discovery Foundation, Cognitive Vitality report on psilocybin. https://www.alzdiscovery.org/uploads/cognitive_vitality_media/Psilocybin.pdf
Penn Memory Center. Can psychedelics help patients with dementia? https://pennmemorycenter.org/psychedelics-dementia/
Eleusis Phase 1 trial of LSD in healthy older volunteers. https://www.alzheimer-europe.org/news/eleusis-reports-results-phase-i-trial-lsd-older-healthy-participants
AI disclosure: AI (Claude Cowork) was used to facilitate access to research and scientific data, assist with drafting and organizing text, and provide error checking. The author generated the underlying intellectual ideas and research questions, interpreted the scientific literature, formulated the essay’s conclusions, verified all sources, and made all other decisions about intellectual content.
Thanks for sharing.
Could you reflect and write about psychedelics and their impact or effect on neuroplasticity, and what might be some possibilities if this were proven?