Closed-eye hallucinations and closed-eye visualizations (CEV) are a distinct class of hallucination. These types of hallucinations generally only occur when one's eyes are closed or when one is in a darkened room. They are a form of phosphene.
Level 4: Objects and things. At this level, thoughts visually manifest as objects or environments. When this level is reached, the CEV noise seems to calm down and fade away, leaving behind an intense flat ordered blackness. The visual field becomes a sort of active space. A side component of this is the ability to feel motion when the eyes are closed.
Opening the eyes returns one to the normal physical world, but still with the CEV object field overlaid onto it and present. In this state it is possible to see things that appear to be physical objects in the open-eye physical world, but that aren't really there.
| “ | If we remember that the essential difference between what we call the real world and the world of imagination and hallucination, is not the elements of which we build them up but the sequence in which these elements appear... then it follows that the sequences directed from without represent a limitation of the otherwise unlimited combinations of the selective forms released at random from within | |
—- Jurij Moskvitin, Essay on the origin of thought.
A particular blind spot known as the blindspot, or physiological blind spot, or punctum caecum in medical literature, is the place in the visual field that corresponds to the lack of light-detecting photoreceptor cells on the optic disc of the retina where the optic nerve passes through it. Since there are no cells to detect light on the optic disc, a part of the field of vision is not perceived. The brain interpolates the blind spot based on surrounding detail and information from the other eye, so the blind spot is not normally perceived.
Although all vertebrates have this blind spot, cephalopod eyes,
which are only superficially similar, do not. In them, the optic nerve
approaches the receptors from behind, so it does not create a break in
the retina.
The first documented observation of the phenomenon was in the 1660s by Edme Mariotte
in France.
At the time it was generally thought that the point at which the optic
nerve entered the eye should actually be the most sensitive portion of
the retina; however, Mariotte's discovery disproved this theory.
 GJ 1214b orbits close to its host star. (An artist's rendering) Observations using the Hubble telescope now seem to confirm that a large fraction of its mass is water. | ||
