|
Closed-eye Visual
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. Some people report CEV under the influence of psychedelics; these are reportedly of a different nature than the "open-eye" hallucinations of the same compounds. Similar hallucinations that occur due to loss of vision are called "visual release hallucinations". Levels of CEV perception There are five known levels of CEV perception which can be achieved either through chemical stimuli or through meditative relaxation techniques. Level 1 and 2 are very common and often happen every day. It is still normal to experience level 3, and even level 4; however, only a small percentage of the population does this without psychedelic drugs, meditation or extensiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hallucination
A hallucination is a perception in the absence of an external stimulus that has the compelling sense of reality. They are distinguishable from several related phenomena, such as dreaming ( REM sleep), which does not involve wakefulness; pseudohallucination, which does not mimic real perception, and is accurately perceived as unreal; illusion, which involves distorted or misinterpreted real perception; and mental imagery, which does not mimic real perception, and is under voluntary control. Hallucinations also differ from " delusional perceptions", in which a correctly sensed and interpreted stimulus (i.e., a real perception) is given some additional significance. Hallucinations can occur in any sensory modality— visual, auditory, olfactory, gustatory, tactile, proprioceptive, equilibrioceptive, nociceptive, thermoceptive and chronoceptive. Hallucinations are referred to as multimodal if multiple sensory modalities occur. A mild form of hallucination is known as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Level 5 CEV (smaller Version)
Level or levels may refer to: Engineering *Level (optical instrument), a device used to measure true horizontal or relative heights *Spirit level or bubble level, an instrument designed to indicate whether a surface is horizontal or vertical *Canal pound or level *Regrading or levelling, the process of raising and/or lowering the levels of land *Storey or level, a vertical unit of a building or a mine *Level (coordinate), vertical position *Horizontal plane parallel Gaming *Level (video games), a stage of the game *Level (role-playing games), a measurement of character development Music *Level (music), similar to but more general and basic than a chord * "Level" (The Raconteurs song) * ''Levels'' (album), an album by AKA * "Levels" (Avicii song) * "Levels" (Bilal song) * "Levels" (Nick Jonas song) * "Levels" (Meek Mill song) * "Levels" (NorthSideBenji song), featuring Houdini * "Levels" (Sidhu Moose Wala song) Places *Level Mountain, a volcano in northern British Columbia, Cana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphene
A phosphene is the phenomenon of seeing light without light entering the eye. The word ''phosphene'' comes from the Greek words ''phos'' (light) and ''phainein'' (to show). Phosphenes that are induced by movement or sound may be associated with optic neuritis. Phosphenes can be induced by mechanical, electrical, or magnetic stimulation of the retina or visual cortex, or by random firing of cells in the visual system. Phosphenes have also been reported by meditators (called '' nimitta''), people who endure long periods without visual stimulation (the prisoner's cinema), or those who ingest psychedelic drugs. Causes Mechanical stimulation The most common phosphenes are pressure phosphenes, caused by rubbing or applying pressure on or near the closed eyes. They have been known since antiquity, and described by the Greeks. The pressure mechanically stimulates the cells of the retina. Experiences include a darkening of the visual field that moves against the rubbing, a diffus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Field Entoptic Phenomenon
The blue field entoptic phenomenon is an entoptic phenomenon characterized by the appearance of tiny bright dots (nicknamed blue-sky sprites) moving quickly along undulating pathways in the visual field, especially when looking into bright blue light such as the sky. The dots are short-lived, visible for about one second or less, and travel short distances along seemingly random, undulating paths. Some of them seem to follow the same path as other dots before them. The dots may appear elongated along the path, like tiny worms. The dots' rate of travel appears to vary in synchrony with the heartbeat: they briefly accelerate at each beat. The dots appear in the central field of view, within 15 degrees from the fixation point. The left and right eye see different, seemingly random, dot patterns; a person viewing through both eyes sees a combination of both left and right visual field disturbances. While seeing the phenomenon, lightly pressing inward on the sides of the eyeballs at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floater
Floaters or eye floaters are sometimes visible deposits (e.g., the shadows of tiny structures of protein or other cell debris projected onto the retina) within the eye's vitreous humour ("the vitreous"), which is normally transparent, or between the vitreous and retina.Cline D; Hofstetter HW; Griffin JR. ''Dictionary of Visual Science''. 4th ed. Butterworth-Heinemann, Boston 1997. They can become particularly noticeable when looking at a blank surface or an open monochromatic space, such as a blue sky. Each floater can be measured by its size, shape, consistency, refractive index, and motility. They are also called ''muscae volitantes'' (Latin for 'flying flies'), or ''mouches volantes'' (from the same phrase in French). The vitreous usually starts out transparent, but imperfections may gradually develop as one ages. The common type of floater, present in most people's eyes, is due to these degenerative changes of the vitreous. The perception of floaters, which may be annoying ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entoptic Phenomena
Entoptic phenomena (), occasionally and incorrectly referred to as entopic phenomena, are visual effects whose source is within the human eye itself. In Helmholtz's words: "Under suitable conditions, light falling on the eye may render visible, certain objects within the eye itself. These perceptions are called ''entoptical''." Overview Entoptic images have a physical basis in the image cast upon the retina. Hence, they are different from optical illusions, which are caused by the visual system and characterized by a visual percept that (loosely said) appears to differ from reality. Because entoptic images are caused by phenomena within the observer's own eye, they share one feature with optical illusions and hallucinations: the observer cannot share a direct and specific view of the phenomenon with others. Helmholtz commented on entoptic phenomena which could be seen easily by some observers, but could not be seen at all by others. This variance is not surprising because the sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palinopsia
Palinopsia (Greek: ''palin'' for "again" and ''opsia'' for "seeing") is the persistent recurrence of a visual image after the stimulus (psychology), stimulus has been removed. Palinopsia is not a diagnosis; it is a diverse group of pathology, pathological visual symptoms with a wide variety of causes. Visual perseveration is Synonym, synonymous with palinopsia. In 2014, Gersztenkorn and Lee comprehensively reviewed all cases of palinopsia in the literature and subdivided it into two clinically relevant groups: illusory palinopsia and hallucinatory palinopsia. Hallucinatory palinopsia, usually due to seizures or visual pathway#Biology of the visual system, posterior cerebral cortex, cortical lesions, describes afterimages that are formed, long-lasting, and high resolution. Illusory palinopsia, usually due to migraines, closed head injury, head trauma, prescription drugs, visual snow syndrome or hallucinogen persisting perception disorder (HPPD), describes afterimages that are affecte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonin
Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, memory, and physiological processes such as vomiting and vasoconstriction. In the CNS, serotonin regulates mood, appetite, and sleep. Most of the body's serotonin—about 90%—is synthesized in the gastrointestinal tract by enterochromaffin cells, where it regulates intestinal movements. It is also produced in smaller amounts in the brainstem's raphe nuclei, the skin's Merkel cells, pulmonary neuroendocrine cells, and taste receptor cells of the tongue. Once secreted, serotonin is taken up by platelets in the blood, which release it during clotting to promote vasoconstriction and platelet aggregation. Around 8% of the body's serotonin is stored in platelets, and 1–2% is found in the CNS. Serotonin acts as both a vasoconstrictor and vas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamus
The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, known as the thalamocortical radiations, allowing hub (network science), hub-like exchanges of information. It has several functions, such as the relaying of sensory neuron, sensory and motor neuron, motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, the thalami are paramedian symmetrical structures (left and right), within the vertebrate brain, situated between the cerebral cortex and the midbrain. It forms during embryonic development as the main product of the diencephalon, as first recognized by the Swiss embryologist and anatomist Wilhelm His Sr. in 1893. Anatomy The thalami ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephen LaBerge
Stephen LaBerge (born 1947) is an American psychophysiologist specializing in the scientific study of lucid dreaming. In 1967 he received his bachelor's degree in mathematics. He began researching lucid dreaming for his Ph.D. in psychophysiology at Stanford University, which he received in 1980. He developed techniques to enable himself and other researchers to enter a lucid dream state at will, most notably the MILD technique ( mnemonic induction of lucid dreams), which was used in many forms of dream experimentation. In 1987, he founded The Lucidity Institute, an organization that promotes research into lucid dreaming, as well as running courses for the general public on how to achieve a lucid dream. In the early 1980s, news of LaBerge's research using the technique of signalling to a collaborator monitoring his EEG with agreed-upon eye movements during REM helped to popularise lucid dreaming in the American media. ''Wired'' magazine referred to him as the "Thomas Edison of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lucid Dream
In the psychology subfield of oneirology, a lucid dream is a type of dream wherein the dreamer realizes that they are dreaming during their dream. The capacity to have lucid dreams is a trainable cognitive skill. During a lucid dream, the dreamer may gain some amount of volitional control over the dream characters, narrative, or environment, although this control of dream content is not the salient feature of lucid dreaming. An important distinction is that lucid dreaming is a distinct type of dream from other types of dreams such as prelucid dreams and vivid dreams, although prelucid dreams are a precursor to lucid dreams, and lucid dreams are often accompanied with enhanced dream vividness. Lucid dreams are also a distinct state from other lucid boundary sleep states such as lucid hypnagogia or lucid hypnopompia. In formal psychology, lucid dreaming has been studied and reported for many years. Prominent figures from ancient to modern times have been fascinated by lucid drea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypnosis
Hypnosis is a human condition involving focused attention (the selective attention/selective inattention hypothesis, SASI), reduced peripheral awareness, and an enhanced capacity to respond to suggestion.In 2015, the American Psychological Association Division 30 defined hypnosis as a "state of consciousness involving focused attention and reduced peripheral awareness characterized by an enhanced capacity for response to suggestion". For critical commentary on this definition, see: There are competing theories explaining hypnosis and related phenomena. ''Altered state'' theories see hypnosis as an altered state of mind or trance, marked by a level of awareness different from the ordinary state of consciousness. In contrast, ''non-state'' theories see hypnosis as, variously, a type of placebo effect,Kirsch, I., "Clinical Hypnosis as a Nondeceptive Placebo", pp. 211–25 in Kirsch, I., Capafons, A., Cardeña-Buelna, E., Amigó, S. (eds.), ''Clinical Hypnosis and Self-Regul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
