Researchers are investigating Lanmaoa asiatica, a wild mushroom linked to unusual poisoning cases that cause vivid hallucinations.
Patients in Yunnan Province, China, reported seeing miniature human-like figures after consuming the mushroom.
These visual experiences are classified as Lilliputian hallucinations, a rare phenomenon involving visions of tiny people or animals.
Symptoms reported in poisoning cases include visual disturbances, confusion, dizziness, nausea, and delirium.
Scientists are studying the mushroom to identify the unknown compound responsible for the hallucinations, as it does not contain common hallucinogenic substances like psilocybin.
Researchers are investigating a mushroom species linked to unusual visual hallucinations in people who consume it. Medical reports describe patients seeing miniature human-like figures after eating the mushroom, a rare visual phenomenon known as Lilliputian hallucinations.¹
The mushroom, Lanmaoa asiatica, grows in parts of Asia and is commonly collected and sold as an edible wild mushroom. However, health authorities in China have documented poisoning cases associated with the species, particularly when it is eaten raw or improperly cooked.²
Several hospitals in Yunnan Province in southwestern China have reported clusters of poisoning cases linked to the mushroom. Patients who consumed it developed neurological symptoms including vivid hallucinations, dizziness, confusion, and agitation.³
Doctors treating these cases reported that patients frequently described seeing groups of tiny human-like figures moving around them. Some reported the figures marching, dancing, or interacting with objects in their surroundings.¹
In China, these hallucinations are sometimes described using the phrase “xiao ren ren,” which translates to “little people,” reflecting the miniature human figures reported by patients.¹
Researchers studying the cases noted that many patients described similar hallucinations despite having no prior knowledge of such experiences. This consistency has drawn attention from scientists studying mushroom toxins and perception.¹
Health authorities in Yunnan have reported hundreds of mushroom poisoning cases linked to the species over several years, although most patients recovered after receiving supportive care in hospitals.³
Symptoms typically appear within hours after consumption and may include visual disturbances, delirium, dizziness, nausea, and impaired coordination. In most reported cases, the symptoms resolved within one to three days.³
The hallucinations reported in these poisoning cases belong to a rare visual phenomenon called Lilliputian hallucinations, named after the tiny inhabitants in Jonathan Swift’s novel Gulliver’s Travels.¹
In this type of hallucination, individuals perceive miniature people, animals, or other small figures that appear integrated into the real environment. Patients often describe them walking across surfaces such as tables, floors, or walls.
Medical literature has associated Lilliputian hallucinations with certain neurological conditions, infections, intoxication, and drug reactions. However, cases linked to mushroom consumption remain relatively rare.¹
See more: Fungal Robotics: Scientists Give Mushroom a Robotic Body, Enabling It to Crawl
Despite its association with hallucinations, Lanmaoa asiatica is considered an edible wild mushroom in some regions of China and is often sold in local markets.²
The species belongs to the Boletaceae family, a group that includes many edible bolete mushrooms. It has a reddish cap and typically grows in forests where it forms a symbiotic relationship with Yunnan pine trees (Pinus yunnanensis).²
Researchers believe that improper preparation may play a role in poisoning cases. Reports indicate that hallucinations occur more frequently when the mushroom is eaten raw or insufficiently cooked.³ ⁴
Local food safety campaigns in Yunnan regularly warn residents about the risks associated with wild mushrooms, as the region reports some of the highest numbers of mushroom poisoning cases in China each year.³ Yunnan Province reports some of the highest numbers of wild mushroom poisoning cases in China each year because foraging and consumption of wild mushrooms are common seasonal practices in the region.¹
Scientists have not yet identified the compound responsible for the hallucinations associated with the mushroom.
Laboratory analyses have shown that the mushroom does not contain common hallucinogenic substances such as psilocybin, psilocin, or muscimol, which are found in other psychoactive mushrooms.²
This finding suggests that Lanmaoa asiatica may contain a previously unidentified chemical compound capable of affecting perception.
Researchers from institutions including the Natural History Museum of Utah and the University of Utah have examined samples of the mushroom to analyze its chemical composition and biological effects.²
Understanding how the mushroom causes these hallucinations could help scientists better understand the neurological mechanisms involved in visual perception and toxin related hallucinations.
David Robson. “The Mysterious Mushroom That Makes You See Tiny People.” BBC Future. January 21, 2026.
https://www.bbc.com/future/article/20260121-the-mysterious-mushroom-that-makes-you-see-tiny-people
Colin Domnauer. “Experts Explore New Mushroom Which Causes Fairytale Hallucinations.” Natural History Museum of Utah.
https://nhmu.utah.edu/articles/experts-explore-new-mushroom-which-causes-fairytale-hallucinations
Jennifer Nalewicki. “A Mushroom Is Sending Hundreds of People to the Hospital With Bizarre Hallucinations.” Popular Mechanics.
https://www.popularmechanics.com/science/a70698051/mushroom-bizarre-hallucination/
Cody Cottier. “This Popular Culinary Mushroom Turns Meals Into Visions.” Discover Magazine.
https://www.discovermagazine.com/this-popular-culinary-mushroom-turns-meals-into-visions-making-people-see-little-elves-48611
(Rh/MSM)