Im sure many have experienced the trail effect many hallucinogens cause. There are a variety of forms some being ghost images following an object by about half a foot or so and then there are persistant solid trails such as those caused by Dextromethorphan and the likes.

My question is... What are they and whats there cause?

Are they in the eye or are they an artifact of the brain?

I experience on occassion trails without the use of mind altering substances and am very interested in knowing there root cause and how someone could stimulate there production minus the insain logic that hallucinogens cause. Along with the periods of "trail vision" I notice a significant amount of Synesthesia associated with text mostly but on occassion colored patterns on the walls associated with low frequency sound waves for example,  the sound of a car going by will wash a white wall in a variety of colors mostly bluish colors if im staring at it when the white wall normaly appeared a sight pink to me before I heard the sound. I know it sounds strange but bear with me please im a little odd when it comes to normal brain chemistry.

I feel these two experiances of trails and synesthesia are closely related but don't know much about the cause of either other then some "mess up" in the brain and a possible cross wiring of some sort.

Intesting you mentioned the dim cell phone because thats exactly what triggered me to come in and type this thread. Iv noticed other abnormalitys the past couple days like "the nonexisting cat" as I call it or the visualation of an animal appearing to run around the house or what not never reaching the center of vision.

The dim cell phone produced noticable trails where as when its fully powered the trail is diminished.

No I think they are highly related and the flashes that appear as an animal running are really trails of an object lost in the corner of vision.

The carpet thing you mentioned is typical of bipolar patiants according to one of my doctors. What I see is images formed as paterns that DO exist but most people just dont see them. Like what I first discribed to my doc during intake "If I stare at the carpet that patch there looks like micky mouse".... Paterns are everywhere and at times it drives me nuts. I do feel that dialated pupils are part of it but they are possibly an effect of whats causing the trails and not a direct cause. IE what triggers dialation also triggers trails.

Hey! You are meant to read my posts!

You know if it was an easy answer it would have been explained already!

http://127.0.0.1/talk/index.php/topic,947.msg11314.html#msg11314

That is a theory BTW;

The most potent and most visual of all hallucinogens are the psychedelic tryptamines, which have chemical structure similar to serotonin and have been shown to be directly active at the 5-HT2A receptor subtype, with slightly lesser affinity at the 2C subtype[1]. Within the brain the highest density of 5-HT2A receptors are expressed on the dendrites of cortical Layer V pyramidal cells[2-3], and the highest density of Layer V dendrites project upward into the dendritic arbors of cortical Layer I, the very outward surface of the cortex. The dendritic arbors of the neocortex contain the highest density of neural receptors in the brain, and are responsible for top-down detail analysis of incoming sensory data[4]. All layers of the neocortex interact with Layer I dendritic arbors – either sending or retrieving impulses in arboreal feedback loops – in order to maintain consistent sensory analysis of external reality from moment to moment. Layer V axonal projections, which connect to lower areas of the brain as well as laterally across the entire cortex, are one of the primary conduits for binding information localized in one area of the neocortex to information localized in another area of the cortex.

"It should be taken as evident that Layer V pyramidal cells are essential in mediating multiple layers of cortical and thalamocortical feedback in order to sustain brainwave cohesion and neural spike synchrony across the entire brain, a process referred to as sensory binding. Given the various circuit functions of Layer V pyramid cells and the prevalence of 5-HT2A receptors mediating these neurons, the notion that 5-HT2A selective agonists can act as both cortical feedback amplifiers and/or interrupters at varying dose ranges is not only likely, it would also explain a wide range of perceptual effects associated with the classic psychedelic trip."

Given the range of serotonergic functionality in the brain we must not ignore the possibility that 5-HT2A selective agonists may have multiple actions at multiple sites, serving to both dampen localized lateral inhibition while simultaneously promoting feedback excitation across the entire cortex. This dualistic effect would become synergistic at higher doses, serving to boost overall brain excitation by flooding disinhibited networks with uninhibited or runaway feedback processing loops. With sufficient loss of lateral inhibition in the visual cortex, even a small amount of perceived motion would cause a standing wave of recurrent excitation along the thalamocortical loop, leading to ghost-like afterimages which fade in the wake of moving objects. This recurrent “echo effect” would presumably apply to all sensation introduced to the sensory processing system, not just visual, similarly explaining a wide variety of subjective effects.


http://www.tripzine.com/pit/html/multi-state-theory.htm

Very excellent paper, you need to read it! It explains the question you asked and much more!

This would seem to imply that substances like DXM are more powerful inhibitors of this area of the brain then things like LSD since the trails caused by DXM+THC combinations have shown themselfs to be solid material looking substance where as those from LSD and MDMA appear ghost like and follow inches behind the object.

Yes, that link explains that the highest concentration of 5-HT2A receptors in the brain is;

"Within the brain the highest density of 5-HT2A receptors are expressed on the dendrites of cortical Layer V pyramidal cells[2-3], and the highest density of Layer V dendrites project upward into the dendritic arbors of cortical Layer I, the very outward surface of the cortex. The dendritic arbors of the neocortex contain the highest density of neural receptors in the brain, and are responsible for top-down detail analysis of incoming sensory data"

The cortical layer is part of the visual cortex of the brain, the dendritic arbors that these cortical Layer V pyramidal cells project towards in the neocortex contain neural receptors that are responsible for analysis of incoming sensory data. So if you think about where these receptors are (surface of the visual cortex) and what they are responsible for it does make more sense.

"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."

Since hallucinogenic tryptamines produce a variety of visual hallucinations at differing dose ranges it is helpful to break down these subjective results by dose range to gauge the level of cortical circuit excitation by corresponding perceptual effects. Even at low doses the most commonly reported visual effects of tryptamine intoxication are pulsating or slowly-rotating closed-eye geometric mandalas, tunnels, and spider webs, also known as phosphenes. Phosphenes are visual artifacts of the spatially organized neural transforms that take place between the spherically organized receptor cells of the retina and the grid-like columnar processing cells in the visual cortex. This visual pathway transformation translates incomplete rings of color and intensity data captured along the retina into the fine lines, shades, and fills we perceive in waking consciousness, yet when the visual processing pathway becomes excited and neural coupling in the thalamocortical loop destabilizes, visual artifacts of these spatially organized networks appear spontaneously within our closed-eye field of vision

Primary Visual Cortex, where the highest concentration of 5-HT2A receptors is highly specialized for processing information about static and moving objects and is excellent in pattern recognition.The occipital cortex is responsible for processing visual stimuli, so this is responsible for how we see and perceive the outside world.


An example, would be the mu-opioid receptors which are found in;
cortex (laminae III and IV)
thalamus
striosomes
periaqueductal gray

The cerebral cortex plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness.

The Thalamus' function includes relaying sensation, special sense and motor signals to the cerebral cortex, along with the regulation of consciousness, sleep and alertness.

Striosomal abnormalities have been associated with neurological disorders, such as mood dysfunction in Huntington’s disease (Tippett et al., 2007), though their precise function remains unknown.

As you can see! also mu-opioid receptors are found in the intestinal tract, which explains constipation and other similar side effects.