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Closed-eye hallucinations and closed-eye visualizations (CEV) are hallucinations that occur when one's eyes are closed or when one is in a darkened room. They should not be confused with phosphenes , perceived light and shapes when pressure is applied to the eye's retina, or some other non-visual external cause stimulates the eye.
He documented it in his 90-year-old grandfather [23] who was nearly blind from cataracts in both eyes. [7] After Bonnet's grandfather received bilateral cataract surgery, his vision evolved from slightly better to complete deterioration over time. [6] It was around this period that his visual hallucinations started. [6]
A phosphene is the perception of light without light actually entering the eye, for instance caused by pressure applied to the closed eyes. A phenomenon that could be entoptical if the eyelashes are considered to be part of the eye is seeing light diffracted through the eyelashes.
Hallucinogen persisting perception disorder (HPPD) is a non-psychotic disorder in which a person experiences apparent lasting or persistent visual hallucinations or perceptual distortions after using drugs, [1] including but not limited to psychedelics, dissociatives, entactogens, tetrahydrocannabinol (THC), and SSRIs.
A familiar phenomenon and example for a physical visual illusion is when mountains appear to be much nearer in clear weather with low humidity than they are.This is because haze is a cue for depth perception, [7] signalling the distance of far-away objects (Aerial perspective).
Visual snow syndrome is often linked to heightened neural sensitivity in the visual system and may require diagnosis and treatment, as it could be associated with underlying eye conditions or neurological disorders. [citation needed] In summary: Visual snow as a temporary occurrence under certain conditions is normal and doesn't require ...
Articles relating to hallucinations, perceptions in the absence of an external stimulus that have the qualities of real perceptions. Hallucinations are vivid, substantial, and are perceived to be located in external objective space. Hallucinations are a combination of 2 conscious states of brain wakefulness and REM sleep.
One example of a pressure phosphene is demonstrated by gently pressing the side of one's eye and observing a colored ring of light on the opposite side, as detailed by Isaac Newton. [ 7 ] [ 8 ] [ 9 ] Another common phosphene is "seeing stars" from a sneeze , laughter, a heavy and deep cough, blowing of the nose , a blow on the head or low blood ...