By James Kent
 
May 23, 2008 - Beta Review
 
Abstract/Summary
 
The most potent tryptamine hallucinogens – such as DMT, psilocybin, and LSD – are all active at the 5-HT2A receptor subtype and all produce similar visual perceptual results that are immediately recognizable as uniquely psychedelic. Although it is widely accepted that selective serotonin receptor subtype 2A agonism is directly responsible for producing the distinct hallucinations seen on a psychedelic trip, no single theory has yet explained why this is so. Utilizing what we know about psychedelic tryptamine receptor interaction, sensory processing circuits in the neocortex, and EEG scans of psychedelics in action, this review will propose a novel multi-state theory of psychedelic action which invokes a variety of neural processing mechanisms, including phase-coupled neural oscillators; network excitation, disinhibition, and destabilization; recurrent feedback excitation; and neural circuit spike synchrony and brainwave cohesion to close the knowledge gap between the pharmaceutical interactions of selective 5-HT2A hallucinogens, their direct effects on perception and consciousness at varying dose ranges, and their potential long-term adverse effects.
 

Figure 3. Akiyoshi Kitaoka "Rotating Snakes" illusion presents an example of radial drift illusion caused by line ambiguity in peripheral visual field.


Beyond the flickering lights and geometric patterns seen in low-dose tryptamine hallucination, mid-dose psychedelic hallucinations generally involve open-eye fluid distortions in the rendering of line, shape, texture, and depth. Subjects under a sub-peak dose often report seeing breathing walls, creeping carpets, melting textures, and flickering geometric patterns crawling over every surface. These effects are all similar in that they represent a destabilization in the visual cortex's ability to hold sharp line, contrast, and texture detail in visual memory, and demonstrate a clear drifting or leaking of contrast information both laterally and radially across the cortex. This fluid-like drifting in the visual field is most prominent in the periphery where the retinal blind-spots are working with incomplete data to begin with.

http://www.tripzine.com/pit/html/multi-state-theory.htm
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I must admit that picture did remind me directly of those agonists at work, especially psilocybin with the definite peripheral movement until you look at it and it stops (then other places start moving) until you look directly at them. Very interesting theory proposed. Some novel 5-HT2A agonists would be worth looking for?

From a chemistry point of view, compounds (5) and (25) are much better to prepare than bromodragonfly for example. As the protection then subsequent deprotection needed while aromatizing the furan rings would not be needed (obviously).

Its 2010 you cant be squirting potent 5-HT2A agonists into monkeys eyes, its not right on so many levels. Unless he specifically asked for it! Then that would be a different story;

That happens to me after driving for a long time on a highway.

Not the same concept though, the first one is because your visual cortex's inability to hold certain types of information in memory.

"These effects are all similar in that they represent a destabilization in the visual cortex's ability to hold sharp line, contrast, and texture detail in visual memory, and demonstrate a clear drifting or leaking of contrast information both laterally and radially across the cortex. This fluid-like drifting in the visual field is most prominent in the periphery where the retinal blind-spots are working with incomplete data to begin with."
http://en.wikipedia.org/wiki/Peripheral_drift_illusion

Whereas;

The motion after-effect (MAE) is a visual illusion experienced after viewing a moving visual stimulus for a time (seconds to minutes) with stationary eyes, and then fixating a stationary stimulus. The stationary stimulus appears to move in the opposite direction to the original (physically moving) stimulus. The motion aftereffect is believed to be the result of motion adaptation.

For example, if one looks at a waterfall for about a minute and then looks at the stationary rocks at the side of the waterfall, these rocks appear to be moving upwards slightly. The illusory upwards movement is the motion aftereffect. This particular motion aftereffect is also known as the waterfall illusion.

Another example can be seen when one looks at the center of a rotating spiral for several seconds. The spiral can exhibit outward or inward motion. When one then looks at any stationary pattern, it appears to be moving in the opposite direction. This form of the motion aftereffect is known as the spiral aftereffect."

"Neurons coding a particular movement reduce their responses with time of exposure to a constantly moving stimulus; this is neural adaptation. Neural adaptation also reduces the spontaneous, baseline activity of these same neurons when responding to a stationary stimulus (see, for example, Barlow & Hill, 1963; Srinivasan & Dvorak, 1979). One theory is that perception of stationary objects, for example rocks beside a waterfall, is coded as the balance among the baseline responses of neurons coding all possible directions of motion. Neural adaptation of neurons stimulated by downwards movement reduces their baseline activity, tilting the balance in favor of upwards movement."
http://en.wikipedia.org/wiki/Motion_aftereffect