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<title>Form constant</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Form constant</span></span>

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<p>A <b>form constant</b> is one of several <a href="Pattern" title="Pattern">geometric patterns</a> which are recurringly observed during <a href="Hypnagogia" title="Hypnagogia">hypnagogia</a>, <a href="Hallucination" title="Hallucination">hallucinations</a> and <a href="Altered_states_of_consciousness" class="mw-redirect" title="Altered states of consciousness">altered states of consciousness</a>.

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<div class="mw-heading mw-heading2"><h2 id="History">History</h2></div>

<p>In 1926, <a href="Heinrich_Kl%C3%BCver" title="Heinrich Klüver">Heinrich Klüver</a> systematically studied the effects of <a href="Mescaline" title="Mescaline">mescaline</a> (<a href="Peyote" title="Peyote">peyote</a>) on the <a href="Subjective_experience" class="mw-redirect" title="Subjective experience">subjective experiences</a> of its users. In addition to producing hallucinations characterized by bright, "highly <a href="Saturation_(color_theory)" class="mw-redirect" title="Saturation (color theory)">saturated</a>" colors and vivid imagery, Klüver noticed that mescaline produced recurring <a href="Geometric_pattern" class="mw-redirect" title="Geometric pattern">geometric patterns</a> in different users. He called these patterns "form constants" and categorized four types: <a href="Lattice_(group)" title="Lattice (group)">lattices</a> (including <a href="Hexagonal_lattice" title="Hexagonal lattice">honeycombs</a>, <a href="Checkerboard" title="Checkerboard">checkerboards</a>, and <a href="Triangle" title="Triangle">triangles</a>), <a href="Spider_web" title="Spider web">cobwebs</a>, tunnels, and <a href="Spiral" title="Spiral">spirals</a>.<sup id="cite_ref-Bressloff2002_1-0" class="reference"><a href="#cite_note-Bressloff2002-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

</p><p>In 1988 <a href="David_Lewis-Williams" title="David Lewis-Williams">David Lewis-Williams</a> and T.A. Dowson incorporated the form constant into his <a href="Entoptic_phenomena_(archaeology)#David_Lewis-Williams's_system" title="Entoptic phenomena (archaeology)">Three Stages of Trance model</a>, the geometric shapes comprising the visuals observed in the model's first stage.

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<div class="mw-heading mw-heading2"><h2 id="Precipitants">Precipitants</h2></div>

<p>Klüver's form constants have appeared in other drug-induced and naturally occurring hallucinations, suggesting a similar physiological process underlying hallucinations with different triggers. Klüver's form constants also appear in <a href="Near-death_experience" title="Near-death experience">near-death experiences</a> and sensory experiences of those with <a href="Synesthesia" title="Synesthesia">synesthesia</a>. Other triggers include <a href="Psychological_stress" title="Psychological stress">psychological stress</a>, <a href="Hypnagogia" title="Hypnagogia">threshold consciousness (hypnagogia)</a>, <a href="Insulin_hypoglycemia" class="mw-redirect" title="Insulin hypoglycemia">insulin hypoglycemia</a>, the delirium of <a href="Fever" title="Fever">fever</a>, <a href="Epilepsy" title="Epilepsy">epilepsy</a>, <a href="Psychosis" title="Psychosis">psychotic episodes</a>, advanced <a href="Syphilis" title="Syphilis">syphilis</a>, <a href="Sensory_deprivation" title="Sensory deprivation">sensory deprivation</a>, <a href="Photostimulation" title="Photostimulation">photostimulation</a>, <a href="Electrical_stimulation" class="mw-redirect" title="Electrical stimulation">electrical stimulation</a>, <a href="Crystal_gazing" title="Crystal gazing">crystal gazing</a>, migraine headaches, <a href="Dizziness" title="Dizziness">dizziness</a> and a variety of <a href="Drug" title="Drug">drug</a>-induced <a href="Substance_intoxication" title="Substance intoxication">intoxications</a>.<sup id="cite_ref-Bressloff2002_1-1" class="reference"><a href="#cite_note-Bressloff2002-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> These shapes may appear on their own or with eyes shut in the form of <a href="Phosphene" title="Phosphene">phosphenes</a>, especially when exerting pressure against the closed eyelid.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>

</p><p>It is believed that the reason why these form constants appear has to do with the way the visual system is organized, and in particular in the mapping between patterns on the <a href="Retina" title="Retina">retina</a> and the columnar organization of the <a href="Visual_cortex#Primary_visual_cortex_(V1)" title="Visual cortex">primary visual cortex</a>. Concentric circles in the retina are mapped into parallel lines in the visual cortex. Spirals, tunnels, lattices and cobwebs map into lines in different directions. This means that if activation spreads in straight lines within the visual cortex, the experience is equivalent to looking at actual form constants.<sup id="cite_ref-Bressloff2002_1-2" class="reference"><a href="#cite_note-Bressloff2002-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

</p><p>Author <a href="Michael_Moorcock" title="Michael Moorcock">Michael Moorcock</a> once observed in print that the shapes he had seen during his <a href="Migraine_headache" class="mw-redirect" title="Migraine headache">migraine headaches</a> resembled exactly the form of <a href="Fractal" title="Fractal">fractals</a>. The diversity of conditions that provoke such patterns suggests that form constants reflect some fundamental property of <a href="Visual_perception" title="Visual perception">visual perception</a>.

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<div class="mw-heading mw-heading2"><h2 id="Cultural_significance">Cultural significance</h2></div>

<p>Form constants have a relationship to some forms of <a href="Abstract_art" title="Abstract art">abstract art</a>, especially the <a href="Visual_music" title="Visual music">visual music</a> tradition, as William Wees noted in his book <i>Light Moving in Time</i> about research done by German psychologist Heinrich Klüver on the form constants resulting from mescaline intoxication. The visual and synaesthetic hallucinations this drug produced resembles, as Wees noted, a listing of visual forms employed in visual music:

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</style><blockquote class="templatequote"><p>[Klüver’s] analysis of hallucinatory phenomena appearing chiefly during the first stages of mescaline intoxication yielded the following form constants: [emphasis original] (a) grating, lattice, fretwork, filigree, honeycomb, or chessboard; (b) cobweb; (c) tunnel, funnel, alley, cone or vessel; (d) spiral. Many phenomena are, on close examination, nothing but modifications and transformations of these basic forms. The tendency towards "geometrization," as expressed in these form constants, is also apparent in the following two ways: (a) the forms are frequently repeated, combined, or elaborated into ornamental designs and mosaics of various kinds; (b) the elements constituting these forms, such as squares in the chessboard design, often have boundaries consisting of geometric forms.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></p></blockquote>

<p>These form-constants provide links between abstraction, visual music and synaesthesia. The cultural significance of form constants, as Wees notes in <i>Light Moving in Time</i> is part of the history of abstract film and video.

</p><p>The practice of the ancient art of <a href="Divination" title="Divination">divination</a> may suggest a deliberate practice of cultivating form constant imagery and using <a href="Intuition_(knowledge)" class="mw-redirect" title="Intuition (knowledge)">intuition</a> and/or imagination to derive some meaning from transient visual phenomena.

</p><p><a href="Psychedelic_art" title="Psychedelic art">Psychedelic art</a>, inspired at least in part by experiences with psychedelic substances, frequently includes repetitive abstract forms and patterns such as <a href="Tessellation" title="Tessellation">tessellation</a>, <a href="Moir%C3%A9_pattern" title="Moiré pattern">Moiré patterns</a> or patterns similar to those created by <a href="Paper_marbling" title="Paper marbling">paper marbling</a>, and, in later years, <a href="Fractal" title="Fractal">fractals</a>. The <a href="Op_art" title="Op art">op art</a> genre of visual art created art using bold imagery very like that of form constants.

</p><p>In <a href="Electroacoustic_music" title="Electroacoustic music">electroacoustic music</a>, Jon Weinel has explored the use of altered states of consciousness as a basis for the design of musical compositions. His work bases the design of sonic materials on typical features of hallucinatory states, and organises them according to hallucinatory narratives. As part of this work, form constants feature prominently as a basis for the design of psychedelic sonic and visual material.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup>

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<ul><li><a href="Biosemiotics" title="Biosemiotics">Biosemiotics</a></li>

<li><a href="Closed-eye_hallucination" title="Closed-eye hallucination">Closed-eye hallucination</a> – Class of hallucination</li>

<li><a href="Entoptic_phenomenon" title="Entoptic phenomenon">Entoptic phenomenon</a> – Visual effect whose source is within the eye itself</li>

<li><a href="Hypnagogia" title="Hypnagogia">Hypnagogia</a> – State of consciousness leading into sleep</li>

<li><a href="Kaleidoscope" title="Kaleidoscope">Kaleidoscope</a> – Optical instrument to view patterns due to repeated reflection</li>

<li><a href="Mandala" title="Mandala">Mandala</a> – Spiritual and ritual symbol in Hinduism, Jainism and Buddhism</li>

<li><a href="Paisley_(design)" title="Paisley (design)">Paisley (design)</a> – Textile design with a teardrop motif</li>

<li><a href="Pattern_recognition" title="Pattern recognition">Pattern recognition</a> – Automated recognition of patterns and regularities in data</li>

<li><a href="Psychophysics" title="Psychophysics">Psychophysics</a> – Branch of knowledge relating physical stimuli and psychological perception</li>

<li><a href="Qualia" title="Qualia">Qualia</a> – Instances of subjective experience</li>

<li><a href="Religion_and_drugs" title="Religion and drugs">Religion and drugs</a> – Attitude towards the use of drugs in several religions</li>

<li><a href="Visual_cortex" title="Visual cortex">Visual cortex</a> – Region of the brain that processes visual information</li>

<li><a href="Visual_snow" class="mw-redirect" title="Visual snow">Visual snow</a> – Visual impairment<span style="display:none" class="category-annotation-with-redirected-description">Pages displaying short descriptions of redirect targets</span></li>

<li><a href="Visual_system" title="Visual system">Visual system</a> – Body parts responsible for vision</li>

<li><a href="Uniform_tilings_in_hyperbolic_plane" title="Uniform tilings in hyperbolic plane">Uniform tilings in hyperbolic plane</a> – Symmetric subdivision in hyperbolic geometry</li></ul>

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<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFBressloffCowan,_Jack_D.Golubitsky,_MartinThomas,_Peter_J.2002" class="citation journal cs1"><a href="Paul_Bressloff" title="Paul Bressloff">Bressloff</a>, Paul C.; Cowan, Jack D.; Golubitsky, Martin; Thomas, Peter J.; Weiner, Matthew C. (March 2002). "What Geometric Visual Hallucinations Tell Us About the Visual Cortex". <i>Neural Computation</i>. <b>14</b> (3): <span class="nowrap">473–</span>491. <a href="CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.146.572">10.1.1.146.572</a></span>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1162%2F089976602317250861">10.1162/089976602317250861</a>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/11860679">11860679</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:207683037">207683037</a>.</cite></span>

</li>

<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><cite id="CITEREFTyler1978" class="citation journal cs1">Tyler, CW (1978). "Some new entoptic phenomena". <i>Vision Research</i>. <b>18</b> (12): <span class="nowrap">1633–</span>9. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2F0042-6989%2878%2990255-9">10.1016/0042-6989(78)90255-9</a>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/726316">726316</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:30888279">30888279</a>.</cite></span>

</li>

<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">Wees, William C. Light Moving in Time: Studies in the Visual Aesthetics of Avant-Garde Film, (Berkeley: University of California Press, 1992), p. 66.</span>

</li>

<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text">Weinel, J. <a rel="nofollow" class="external text" href="http://www.jonweinel.com/PDF/Weinel_2013_AM13_Visual_Patterns.pdf">"Visual patterns of hallucination as a basis for sonic arts composition"</a>. <i>Proceedings of Audio Mostly 2013</i>.</span>

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<div class="mw-heading mw-heading2"><h2 id="Sources">Sources</h2></div>

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<ul><li><a href="Susan_Blackmore" title="Susan Blackmore">Blackmore, Susan</a>. Dying to Live: Near-Death Experiences. Buffalo, NY: Prometheus Books, 1993.</li>

<li><a href="Richard_Cytowic" title="Richard Cytowic">Cytowic, Richard E.</a>, <a href="The_Man_Who_Tasted_Shapes" title="The Man Who Tasted Shapes">The Man Who Tasted Shapes</a>.</li>

<li>Ermentrout, G.B. and Cowan, J.D., "A mathematical theory of visual hallucination patterns." <i>Biol. Cybernet.</i> 34 (1979), no. 3, 137–150.</li></ul>

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<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><a rel="nofollow" class="external text" href="http://www.entheology.org/edoto/anmviewer.asp?a=165">Text from "Hallucinogens and Creativity" page by Susan Opar</a></li>

<li><a rel="nofollow" class="external text" href="https://archive.org/details/redwood_center_2006_02_14_cowan">"Spontaneous pattern formation in large scale brain activity: what visual migraines and hallucinations tell us about the brain"; online video of lecture by Jack Cowan</a></li>

<li><a rel="nofollow" class="external text" href="http://www.math.utah.edu/~bresslof/publications/Colston.pdf">"Spontaneous pattern formation in the primary visual cortex"</a></li>

<li><a rel="nofollow" class="external text" href="http://www.math.utah.edu/~bresslof/publications/01-3.pdf">free version of "What Geometric Visual Hallucinations Tell Us about the Visual Cortex"</a></li></ul>

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</style><div id="Phenomena_of_the_visual_system91" style="font-size:114%;margin:0 4em">Phenomena of the <a href="Visual_system" title="Visual system">visual system</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Entoptic_phenomenon" title="Entoptic phenomenon">Entoptic phenomena</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Blind_spot_(vision)" title="Blind spot (vision)">Blind spot</a></li>

<li><a href="Phosphene" title="Phosphene">Phosphene</a></li>

<li><a href="Floater" title="Floater">Floater</a></li>

<li><a href="Afterimage" title="Afterimage">Afterimage</a></li>

<li><a href="Haidinger's_brush" title="Haidinger's brush">Haidinger's brush</a></li>

<li><a href="Prisoner's_cinema" title="Prisoner's cinema">Prisoner's cinema</a></li>

<li><a href="Blue_field_entoptic_phenomenon" title="Blue field entoptic phenomenon">Blue field entoptic phenomenon</a></li>

<li><a href="Purkinje_images" title="Purkinje images">Purkinje images</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other phenomena</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Scintillating_scotoma" title="Scintillating scotoma">Scintillating scotoma</a></li>

<li><a href="Palinopsia" title="Palinopsia">Palinopsia</a></li>

<li><a href="Visual_snow" class="mw-redirect" title="Visual snow">Visual snow</a></li>

<li><a href="Afterimage" title="Afterimage">Afterimage on empty shape</a></li>

<li><a href="Cosmic_ray_visual_phenomena" title="Cosmic ray visual phenomena">Cosmic ray visual phenomena</a></li>

<li><a href="Closed-eye_hallucination" title="Closed-eye hallucination">Closed-eye hallucination</a></li></ul>

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