Depth perception distortions
Depth perception distortions are alterations in how a person perceives the distance of various objects within their visual field.  During this state, the various layers of scenery can become exaggerated, skewed, or completely rearranged.     An example of this could be the swapping of layers in a given environment, in which objects in the background begin to appear as if they are in the foreground and objects in the foreground appear as if they are in the background. In other instances, the same distortion is applied to the entire visual field, such as everything appearing small and distant or large and near.
Another example of these distortions is the complete loss of depth perception.   This occurs when the different sections of a scene appear to unify into a flat 2-dimensional image regardless of their actual distance from each other and the observer.
Depth perception distortions are often accompanied by other coinciding effects, such as perspective distortions and drifting. They are most commonly induced under the influence of moderate dosages of psychedelic compounds, such as LSD, psilocybin, and mescaline.
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