Symmetrical texture repetition
Symmetrical texture repetition is the perception of textures becoming mirrored repeatedly over their own surface in an intricate and symmetrical fashion that is consistent across itself. This maintains the same level of detail no matter how closely one attempts to look at the distortion and tends to remain most prominent within one's peripheral vision. It usually manifests itself in rough textures, such as grass, carpets, tree bark, and asphalt.
If one stares at a fixed point during this state, the symmetrical texture repetition may progressively increase and further tesselate into more complex forms. However, this progression of complexity will usually reset back to baseline as soon as one double takes.
Symmetrical texture repetition is often accompanied by other coinciding effects, such as increased pareidolia   and transformations. This can result in the appearance of an array of abstract forms and imagery embedded within the symmetry. It is most commonly induced under the influence of mild dosages of psychedelic compounds, such as LSD, psilocybin, and mescaline. However, it can also occur less commonly under the influence of MDMA and certain dissociatives, such as 3-MeO-PCP or DXM.
It is worth noting that to accurately replicate the appearance of this effect through the use of image editing software, all one needs to do is simply mirror a texture across itself in a symmetrical manner. This may suggest that a similar process is occurring within the brain, perhaps by filling in missing details by taking visual data from one's central line of sight and mirroring it across the peripheral vision in a manner that results in a symmetrical tessellation of the texture.
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