Neurosensory Research Foundation

09/24/2026

Prevalence-focused revision

The study is the largest retrospective cohort to date on hallucinogen persisting perception disorder (HPPD), using TriNetX electronic health records to compare 25,778 HPPD patients with population controls and psychedelic-using controls. Importantly, it does not provide a true general-population prevalence estimate for HPPD; the 25,778 figure is a clinical cohort count, not a population prevalence.

Prevalence of comorbid conditions before HPPD diagnosis:

· Depressive episodes: 29.2%
· Anxiety disorders: 26.2%
· Chronic pain: 15.9%
· Headache syndromes: 14.7%
· Post-viral fatigue: 12.3%
· Fibromyalgia: 6.7%
· ADHD: 6.6%

Anxiety and functional somatic syndromes were significantly more prevalent in HPPD patients than in psychedelic-using controls. Among psychedelic users, pre-existing anxiety (OR 1.5) and post-viral fatigue (OR 1.9) predicted later HPPD diagnosis.

After diagnosis, HPPD was associated with higher subsequent prevalence/risk of functional somatic syndromes (OR 2.0) and psychiatric disorders (OR 1.4) compared with psychedelic-using controls. Neurodegenerative disorders were recorded in 2.3% of HPPD patients vs. 1.2% of population controls.

Bottom line: In this clinical cohort, HPPD co-occurs with a high prevalence of anxiety, depression, pain, headache, fatigue, and functional somatic syndromes. However, because the study relies on EHR diagnoses and a selected clinical sample, the true prevalence of HPPD in the general population or among all psychedelic users remains unknown.

An that’s a problem…

Hallucinogen persisting perception disorder (HPPD) is characterised by episodes of altered perception linked to past psychoactive drug use, accompanied by distress and functional impairment. To date, clinical characterisation has been limited in scale. Using TriNetX, a global federated health resear...

09/05/2026

UCLA researchers have discovered two powerful influences that help guide how the human brain forms before birth. Radial glia, stem cells responsible for producing much of the cerebral cortex, change their behavior depending on how they process glucose and on physical contact with signals arriving from the thalamus. Those signals can alter which types of neurons are produced, including upper-layer neurons that are especially prominent in humans.

UCLA researchers have discovered two powerful influences that help guide how the human brain forms before birth. Radial glia, stem cells responsible for producing much of the cerebral cortex, change their behavior depending on how they process glucose and on physical contact with signals arriving fr...

09/04/2026

A patient in their 60s with advanced macular degeneration complicated by bilateral geographic atrophy presented with new-onset visual disturbances shortly after initiation of bupropion for depression.

08/28/2026

This narrative review synthesizes evidence up to July 2026 on psychedelic (psilocybin, L*D, M**A) safety and clinical outcomes, emphasizing that both risks and benefits depend critically on the exposure pattern—defined by dose, frequency, person, and context—rather than compound identity alone. Under supervised clinical administration, transient effects like headache, nausea, and cardiovascular activation are common, while serious reactions (persistent anxiety, suicidality signals, and hallucinogen persisting perception disorder) are uncommon but confirmed, precluding absolute reassurance. The strongest efficacy signals are for M**A-assisted therapy in PTSD and psilocybin-based treatment for depression, though certainty is severely constrained by functional unblinding, selected samples, inconsistent comparators, and recent negative or equivocal primary trials (e.g., the EPISODE trial). Naturalistic studies show vulnerability and context modify outcomes, but frequency is inconsistently measured, and microdosing trials demonstrate limited short-term benefit with unresolved long-term cardiac (5‑HT2B‑mediated valvular risk) and psychiatric safety. The review concludes that evidence must be parsed by specific exposure regimens, and it prioritizes exposure-defined cohorts, active comparators, independent blinded raters, and prospective registries to establish who benefits, who is harmed, and what long-term surveillance is required for repeated use.

Clinical trials and naturalistic studies describe psychedelics under markedly different exposure conditions. This narrative review searched PubMed/MEDLINE, the Cochrane Library, ClinicalTrials.gov, and regulatory sources through 15 July 2026, and examined safety and outcomes across four dimensions o...

08/22/2026

See, it’s all fun and games until it’s not…


This exploratory observational study characterized 13 patients (10 males, mean age 24.3 years) with persistent perceptual disturbances following cannabis or synthetic cannabinoid use. Comprehensive clinical assessments revealed that visual snow was universal (100%), with frequent trailing phenomena (92.3%), halos (84.6%), and color changes (76.9%). A notable novel finding was auditory hypersensitivity in 61.5% of patients. Symptoms typically emerged about 3.2 weeks after cannabis cessation, and all neurological examinations and neuroimaging were normal. Comorbid anxiety was highly prevalent (84.6%), and functional impairment ranged from mild to severe. The authors conclude that this distinct symptom profile—particularly the combination of visual snow, auditory hypersensitivity, and normal neurological findings—suggests a potentially underrecognized complication of cannabis use that warrants further systematic investigation.

08/19/2026

https://www.wesh.com/article/lets-learn-about-perception-with-the-orlando-science-center/73477003

The Science of It: We all perceive the world around us in different ways. But how does it all work?

08/16/2026

A groundbreaking chemogenetic therapy using DREADDs (designer receptors activated by designer drugs) has entered human clinical trials in China, marking a major milestone for the field. Developed twenty years ago by Bryan Roth of UNC, the technique uses a viral vector to introduce a designer receptor gene into specific neurons, which then suppresses neuronal activity when triggered by a small-molecule drug. At least seven trials are now underway targeting intractable epilepsy, Parkinson's disease, and neuropathic pain—conditions that currently may require invasive brain surgery. The news, shared at a U.S. NIH BRAIN Initiative meeting, left American neuroscientists "stunned," with some noting that China has taken a clear lead in this area of neurotechnology. While the approach offers greater precision and potentially fewer side effects than traditional drugs, it carries risks common to viral-vector gene therapies, including severe immune reactions. Nevertheless, researchers believe that if successful, the therapy could pave the way for circuit-based treatments for a wide range of neuropsychiatric diseases.

Chinese researchers are testing DREADDs, a gene therapy to turn down neuronal activity, in the clinic

08/15/2026

This message was recorded in 1992, yet it feels just as powerful to...

08/15/2026

A new psychedelic survey from UCL is seeking to understand how psychedelics and related drugs affect different people across the lifespan.

See details and the link to contribute your experience to psychedelic research below:

https://qualtrics.ucl.ac.uk/jfe/form/SV_a44pPupnpjzL5ie

08/15/2026

Did you know the first documented mention of visual snow appeared in the medical literature over 80 years ago?

🗓️ In 1944, Dr. Frank D. Carroll described patients experiencing persistent visual disturbances, including “snowy vision,” flashing and flickering lights, colored floaters, and other visual phenomena. Although their eye examinations were normal, he proposed that these symptoms originated in the brain rather than the eyes.
This early report marked the beginning of what would eventually become our understanding of Visual Snow Syndrome.

Explore our new Timeline of Visual Snow Syndrome and the Visual Snow Initiative to discover the history of VSS and the key milestones in research, advocacy, recognition, and awareness that have shaped the field over the decades.

https://www.visualsnowinitiative.org/vss-timeline/