Psychedelic Visuals Are Produced in the Backs of Our Eyeballs, New Theory Suggests

The psychedelic experience amounts to a mesmerizing, stupefying, and at times terrifying, divine ride into the cosmos and back. Naturally, the specifics vary wildly, depending on set, setting, and the psychedelic itself – plus the quantity consumed. But when it comes to visual hallucinations, there are some striking similarities that people report. 

The psychonaut may have an open-eyed vision of a fully-fledged animal (with peyote, people often report seeing deers) or creature-like entities. Some people may see faces, objects, and even entire landscapes melting. Stuff may be seen further away than in reality, or appear smaller or bigger than usual. The size of any given environment may be perceived incorrectly due to a phenomenon called metamorphopsia. Others may see faces melting, or as if everything around them was a wax painting bleeding into a bottomless well of reflection.

It is generally understood that the brain is the first site of a process called psychedelic modulation, which occurs after ingesting psilocybin, LSD, DMT, or any other classical psychedelic that binds to 5-HT2A serotonin receptors. But in a new theoretical paper, neuroscientist Zeus Tipado puts forward the idea that this may actually happen in the retina, located in the back of the eyeball.

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This does not necessarily help us understand why we see certain things when we trip (or, why so many people seem to see geometric Aztec images with their eyes closed), but this theory could still bring us to a deeper understanding of how the visual phenomena produced on psychedelics works.

“Amacrine cells are interneuron cells located between the bipolar cells, which are connected to photoreceptors and retinal ganglion cells [and they] form the optic nerve to our brain,” Tipado told DoubleBlind. “These amacrine cells include 5-HT2A receptors (amongst others) and mostly are inhibitory. This means amacrine cells throttle or reduce light information coming from photoreceptors to the rest of the brain.”

Thus, he proposes that while under the influence of psychedelics, the function of amacrine cells is modulated through 5-HT2A activation. This leads to receiving visual imagery that is different than while sober, or not under the influence of psychedelics, as the interneurons in our eyes go haywire as serotonin levels spike.

“Imagine amacrine cells as a bouncer at the club that all light from our world has to get through before it goes to the brain,” Tipado, a doctoral candidate at the University of Maastricht, wrote on X. “If you’re not on the list, then you get bounced right out. But if you’re on the list, these amacrine cells will let you in.”

As the trip gets more intense,  “In a sense, these bouncers at the door of the eye/brain nightclub are no longer bouncing,” he wrote, “everyone is let in the club.”

It’s certainly a fascinating, mind-boggling idea. But not everyone is on board. (Tipado is used to stirring up division, as we saw with his assertions that DMT aliens are figments of psychonauts’ imaginations). Dr. David Luke, associate professor of psychology at the University of Greenwich and co-founding director of Breaking Convention, the psychedelic consciousness conference, suggested that science alone may never provide all of the answers to the source of our visions.

“Psychedelic mental imagery is much more than meets the eye,” he posted on X. Luke also raised questions over the use of a published case study in the paper in which a congenitally blind person was found not to experience visual hallucinations while under the influence of psychedelics.

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“Assuming all congenitally blind people do not get visual imagery on psychedelics based on a case study is horribly premature, and ignores the imagery experiences of 2/3 of this group during [near death experiences],” he said. “What of people with aphantasia who have large doses of potent psychedelics (e.g., DMT) and yet have no closed-eye visual mental imagery, and yet still encounter entities?”

Robin Carhart-Harris, a professor in the Department of Neurology at the University of California, San Francisco, also questioned whether the psychedelics are not, in fact, exciting internal, endogenous architecture and processes.

Tipado replied saying he believes the process is occurring simultaneously with everything in the retinofugal pathway. “Even closed-eye visuals are still working on low-quality visual information seen from the back of our eyelids,” he posted.

Or, maybe they’re coming from a divine power. Or the consciousness of the psychedelic itself.