It's been three hours since you ate two thick tabs of high-grade LSD, and the stuff is really kicking in. You sense this because everything and everyone around you looks weirder and progressively severe as the trip extends. This isn't your first time, but who are you kidding? You're no acid king. You're just another blip on the collective radar of untold millions of garden-variety psychonauts who occasionally swill that brain juice.

You are electric. Your brain is a super-continent only partially charted. Your mind's eye is fire-hosing garbled and complex equations, proofs, and logical dead-ends, and will do so for something like the next 10 hours, possibly longer. You are diving through bottomless fractals and honeycombs. You're scaling lattices and gratings as tall as mountains, and now you're tracing the filigrees and fretwork of the Relief of Time. You're plucking noise out of thin air, damnit, spreading the sonic detritus over your person like some strange sort of salve. You look down at your hands only to see how they've melted to the floor in small, fleshy puddles. You turn to your trip sitter, a trusted friend who appears now to be spewing fire so as to beat back a gaggle of ankle-biting, animatronic elves. The walls are breathing, you swear it. You're tripping.

These are just some of the sort of open-eye distortions, occular tricks, and warped depth perceptions that color long, strange, at times painfully sublime trips down to the Laugh Farm. You're about a third of the way there by now and it's like you haven't even blinked, to say nothing of what you might also have smelled or even tasted to this point of your inner odyssey.

What's foggier is why. Acid, DMT, psilocybin, mescaline, ayahuasca, whatever--it's almost no matter. When you dose your head, why do your eyes pick up certain visual stimuli while blotting out others? Why do some otherwise everyday objects appear stranger or more fragile to you than others? Why do you swear on your life that you see stuff--things, people, the forces of nature--that simply would not be if you weren't nearing peak trip?

To find out, take a good, hard look at yourself tripping face. What you might find is that the why behind the crest and trough of a proper trip's hallucinatory wave is just as intense, even life affirming as the what, the raw visualizations themselves--perhaps even more so. And yet why? Why do we see we what we see when tripping?

It's a riddle that's lingered for about as long as humans have been deliberately altering their minds with chemicals, which is to say for all of human history. To this day, even with ever-advancing brain-imaging capabilities, it continues to confound and intrigue scientists, researchers, amateur chemists, and committed and casual psychonauts alike. To pull just one take out of a growing corpus of rigorous psychedelic study, the question of why we see such things on psychedelics lays at the heart of a paper (.pdf) published August 2000 in the journal of the Royal Society that plumbed the depths of the "striking" visual experience of seeing geometric visual hallucinations.

One look at its title ("Geometric visual hallucinations, Euclidean symmetry and the functional architecture of striate cortex") and byline, which includes mathematicians from the Universities of Utah, Chicago, and Houston, plus researchers from the Salk Institute for Biological Studies and the National Institutes of Health, and what's clear is our understanding of why, exactly, we see precisely what we see (or what we think appears in our fields of view) when tripping rests as much on basic geometry as it does neurology, psychopharmacology and the cognitive sciences writ large.

Alright, maybe not _basic_-basic geometry. This is dense stuff. Are you up on Rayleigh-Schrodinger perturbation theory and non-linear stability analyses the likes of Liapunov-Schmidt reduction? Because if you're neither a math ace nor on acid, working through the study may have you feeling like you are in fact tripping on LSD.

Not to say the paper doesn't deserve a close read, or that how I'm about to distill its findings does the study true justice. But the idea is that in modeling form constants using numbers and shape theory the researchers first posited that "patterns of connection" linking the retina, the visual cortex and its neuronal circuitry bore the wellspring over which classic psychedelic visuals bubble.

In the end, the researchers found a close relationsip between form constants, those geometric patterns regularly observed in altered states of consciousness, and planforms, or the contours of objects seen from above. These results hinged on the "detailed speculation" of lateral connectivity in the visual cortex, brain activity central to our ability to recognize an object, its contours, and how it relates with other objects.

As such, a curious possibility emerged. If "the cortical mechanisms by which geometric hallucinations are generated" are indeed housed in the visual cortex, the researchers wrote, it stands to reason that those very mechanisms responsible for psychedelia's geometric visuals are fundamentally akin to those that allow humans to make sense of contours and edges. Which would certainly cut an entirely new slant along the Edge.

But don't just take my word for it. Go read the paper. It's a trip.

It's also just one study. And though it's certainly true that claims of being at the threshold of a psychedelic renaissance in 2013 may not sound that crazy--Rick Doblin, head of the Multidisciplinary Association for Psychedelic Studies, recently told me that psychedelic research "is flourishing"--it's still difficult, particularly in the US, to obtain most research-grade psychedelics for clinical trial. Which is why something like The Visual Components of a Psychedelic Experience could be valuable to deepening our understanding of why we visualize what we do on doses.

Visual Components is exhaustive but free of most of the jargon and wonk that can turn off lay people to the topic. Published in 2011 on the blog Disregard Everything I Say, the entry--which should nevertheless be taken with a moderately-sized grain of salt, as you would with an Erowid or any other crowd-sourcey online compendium of drugs knowledge--apparently factors LSD, LSA, psilocybin, DMT, ayahuasca, mescaline, Bufotenin, 5meoDMT, AMT, Harmine, Harmaline, MDA, and the 2Cx and DOx chemical classes into laying out the visual and cognitive components of the psychedelic experience.

So even if we should disregard some of Disregard Everything I Say's taxonomy of psychedelic visual phenomena, which breaks out in four levels of increasing intensity (dosages), it's still worth noting, if only to highlight the various shades of what we think we know about seeing things on drugs.

SHARPER VISION

See: heightened visual acuity, color and pattern-recognition enhancement. You have to start somewhere, right?

A SLIGHT TWIST

Or, "distortion, or visual alteration." This next phase includes visual drifting, as seen in Breathing Wall by Bill Meyers-Riggs, a moderately-intense rendition of the drift effect at highly accurate levels of detail, and its four subtypes: 1. morphing, 2. breathing, 3. melting, and 4. flowing. Visual drifting can manifest over four distinct channels of visual intensity: peripheral, direct, distinct, all-encompassing.

Filling out this second tier of visual cues are color shifts, warped depth perceptions, light tracers (transparent, translucent, opaque, and all-encompassing), symmetrical texture repetition (above), and the fracturing glare known as scenery slicing.

MENTAL MATH

Level 3 is part and parcel of the aformentioned geometic visual study. Here we get visual geometry; its iterations, from least dramatic and incomprehensible to most profound, include virtual noise, motion and color, partially-defined and fully-defined geometry, three-dimensional geometry, overriding physical perception, and what DEIS calls "Level 7A" and "7B"--"exposure to entirety of neurological structure" and "exposure to inner mechanism of human consciousness," respectively. You can see the peak up ahead.

SEEING WHAT ISN'T

The end. This last phase is hallucinatory--imagery, transformations, and proper hallucinations, of which there are four types: autonomous entities (McKenna's famed machine elves); landscapes; sceneries and settings; concepts; and scenarios and plots.

For the uninitiated, it's almost not even worth trying to wrap your head around what it's like seeing imaginary shit on acid or whatever. To be sure, an experiment in replicating the psychedelic experience accurately and with care is becoming a bit of a cottage industry in center corners of the internet. Take Form Constant's Texture Breathing, as seen at the top of this post.

But see, you don't need that. You're only three hours in, remember, and should maybe just defer to what noted neurologist and psychonaut Oliver Sacks says in his book Musicophilia. "Every act of perception," Sacks writes, "is to some degree an act of creation, and every act of memory is to some degree an act of imagination."

If the shape of psychedelia to come is just all in our heads, well, here's looking out.

Front image via Flickr / CC.

Reach Brian at brian@motherboard.tv. @thebanderson