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. Sep 05, 2016 four visual disturbances and phenomena we all experience. Entoptic phenomena as universal trance phenomena vividlife. Around a dim light viewed in adark room faint bluegray arcs can be seen which occupy thatpart of the visual field corresponding to the retina where the arcuate nerve fiber bundle passes from macularganglion cell bodies to the optic nerve. Entoptic definition of entoptic by medical dictionary. Suggestions for spiritual approaches to migraine headaches. Lewiswilliams also argues that the shininess of quartz represents the entoptic phenomena of the first stage of altered consciousness 2002.
Mar 15, 2017 entoptic phenomena were first described by johann purkinje in the early 1800s, to describe the fleeting, black afterimage of retinal vasculature, later coined the purkinje tree. Entoptic phenomenon synonyms, entoptic phenomenon pronunciation, entoptic phenomenon translation, english dictionary definition of entoptic phenomenon. The images are generally clearer in the dark and when you are rel. Entoptic imagery and altered states of consciousness.
In archaeology, the term entoptic phenomena relates to visual experiences derived from within the eye or brain as opposed to externally, as in normal vision. Observations on entoptic phenomena jama ophthalmology. Entoptic phenomena were first described by johann purkinje in the early 1800s, to describe the fleeting, black afterimage of retinal vasculature, later coined the purkinje tree. The label artwork a is a painting by weinel, which is based on kluvers form constants. Entoptic images are visual effects which originate within the visual processing system of the observer. During the 1920s, some theosophists, unaware of the physical explanation, maintained that the moving spots seen in the blue field entoptic phenomenon were vitality globules related to the concept of prana in yoga. Entoptic phenomena in audio, as presented on limited edition transparent orange vinyl. We are still physically very much the huntergatherers we were prior to agrarianism. In the mid1990s i met a man named nestor living in the solitude of the hilly emmental region of switzerland. Yet, there is enough commonality between the main entoptic phenomena that their physical origin is now wellunderstood.
Dec 24, 2014 smart news keeping you current meet the culprits behind bright lights and strange floaters in your vision socalled entoptic phenomena remind us that what we see isnt always a clear view of the. Entoptic phenomenon definition of entoptic phenomenon by. Get a printable copy pdf file of the complete article 2. Dowson 1988 in their article the signs of all times propose a neurobridge backwards in time to the upper palaeolithic by which we can gain insight into the nature of the origins of art.
If so, share your ppt presentation slides online with. Download fulltext pdf blue field entoptic phenomenon in cataract patients article pdf available in archives of ophthalmology 976. Entoptic phenomena in upper palaeolithic art and comments and reply. Dec 12, 2016 they also cant be photographed, so i can only show you drawings we will cover these phenomena from anterior to posterior eye structures because entoptic phenomena improve your understanding of the physiology of vision and visual perception, and can sometimes be used to monitor ocular disease 5. Any visual sensation arising from within the eyeball. Retinal entoptic phenomena have been used for many years in studies of retinal physiology. Our nervous system has not changed much in the past 100,000 years. Many of these phenomena can be of diagnostic value, particularly in cases where adequate ophthalmoscopic examination is difficult due to medial opacities. There is no prescribing literature on prozac or other anxietydepression medications causing increased entoptic phenomena. Occasionally, these are called entopic phenomena, which is probably a typographical mistake. Entoptic definition of entoptic by the free dictionary. Entoptic images have a physical basis in the image cast upon the retina. Entoptic image quality of the retinal vasculature sciencedirect. They also cant be photographed, so i can only show you drawings we will cover these phenomena from anterior to posterior eye structures because entoptic phenomena improve your understanding of the physiology of vision and visual perception, and can sometimes be used to monitor ocular disease 5.
Perhaps a better use of you time and money would be to try and get rid of the hypochondriasis. Entoptic phenomena as universal trance phenomena abracad, october 16, 2010 categories. Opto6124 perception scott stevenson entoptic phenomena vision is supposed to tell us about the world beyond ourselves, but sometimes what we see is caused by the visual apparatus itself. Jan 29, 2010 the role of higher cortical visual centres in the appearance of entoptic phenomena also cannot be ruled out in some cases, although their contribution is difficult to analyse.
In the 19th century, european and american opticians, physiologists and philosophers developed a broad interest in entoptic phenomena. Entoptic phenomena as universal trance phenomena new age. Both informative and alluring, watching this map work in real time has the strangely calming effect of watching a familiar object transform into a mythical creature. Typical visual phenomena include a flicker scintillation and the visual field defect scotoma.
Full text full text is available as a scanned copy of the original print version. Strictly speaking, entoptic phenomena are concerned with the autovisualization of certain structures within the eye through the propitious arrangement of incident light. The blue field entoptic phenomenon bfe, which allows the observation of ones own leukocytes flowing in macular retinal capillaries, was used to predict postoperative macular function in 6. Under suitable conditions light falling on the eye may render visible certain objects within the eye itself. Ppt entoptic phenomena of retinal origin powerpoint. Opto6124 perception scott stevenson entoptic phenomena shadows.
Since it originates within the visual system, entoptic imagery. The archaeology of rock art and western philosophy pieces of prehistoric art discovered all around the world suggest that optical illusions or entoptic phenomena may have been part of the artistic. Health, general eye properties images, optical optical images optometrists vocational guidance visual perception. Four visual disturbances and phenomena we all experience. In the signs of upper palaeolithic art lewiswilliams and dowson see entoptic phenomena very similar to those produced by people in altered states of consciousness today. I have never heard of hypnotherapy getting rid of entoptic phenomena. Apr 07, 20 psychology definition of entoptic phenomena. The blue entoptic phenomenon is the result of incorrect brain filtering of the shadows cast by the blood. Common entoptic phenomena and their clinical significance.
Entoptic phenomena of retinal origin is the property of its rightful owner. Adaptive principle the compositions contained within entoptic phenomena in audio weinel, 2014 are. Entoptic definition at, a free online dictionary with pronunciation, synonyms and translation. These structures may be normal to the eye or they may be pathologic imperfections, such as opacities in the vitreous or lenticular.
Meet the culprits behind bright lights and strange floaters. Accurate imaging of the retinal vasculature is an essential component in the successful diagnosis and treatment of numerous retinal diseases e. To generate and study entoptics, they conducted experiments by stimulating brain and retina, electrically at first, later also with mindaltering substances. Pdf blue field entoptic phenomenon in cataract patients. Apr 05, 20 a favorite discovery at the moma last week. Find entoptic phenomena information, treatments for entoptic phenomena and entoptic phenomena symptoms. All these appearances can be understood as entoptic phenomena, a medical term for a specific group of subjective visual phenomena, some of which we know from more common, everyday. In this respect they differ slightly from the medical definition, which defines entoptic phenomena as only applying to sources within the eye, not the brain. Jun 22, 2006 this animation was created in after effects based on what is known as entoptic phenomena. The term entoptic comes from the greek for within vision, indicating that the images come from anywhere within the optic system, between the eye itself and the neural cortex where signals from the optic nerve are interpreted. Because they come from inside they are called entoptic phenomena. Afterimage of a grating is seen first in a central region of the field, later in peripheral locations.
161 793 1220 185 145 1425 84 160 586 653 1451 925 938 859 1186 1467 133 213 487 724 1561 1339 435 1362 1111 1160 714 778 65 1495 72 1217 1100 210 572