Difference between revisions of "Ehrenstein illusion" - New World Encyclopedia

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[[Category:Politics and social sciences]]
 
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[[Category:Psychology]]
 
[[Category:Psychology]]
 
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[[Image:Ehrenstein2.gif|thumb|right|180px|Ehrenstein illusion.]]
 
The '''Ehrenstein illusion''' is an [[optical illusion]] in which a circle appears at the end points of a series of lines. The Ehrenstein illusion is one of the most popular subjective contour illusions (illusions that create the impression of a shape even though a large portion of the contour is nonexistent.) A similar effect can be found in the [[Kanizsa triangle]].
 
The '''Ehrenstein illusion''' is an [[optical illusion]] in which a circle appears at the end points of a series of lines. The Ehrenstein illusion is one of the most popular subjective contour illusions (illusions that create the impression of a shape even though a large portion of the contour is nonexistent.) A similar effect can be found in the [[Kanizsa triangle]].
 
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[[Image:Ehrenstein figure.svg|thumb|Illusion 3,Adding a circle (bottom) destroys the illusion of a bright central disk.]]
 
==Discovery==
 
==Discovery==
The Ehrenstein illusion is named for German psychologist [[Walter Ehrenstein]], who published his findings in 1941 in the German psychology journal ''Zeitschrift für Psychologie'' (150, 83-91). Ehrenstein published his findings as a modification of the [[Hermann grid illusion]].
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The '''Ehrenstein illusion''' is named for [[Germany|German]] [[psychologist]] [[Walter Ehrenstein]], who published his findings in 1941 in the German psychology journal ''Zeitschrift für Psychologie'' (150, 83-91). Ehrenstein published his findings as a modification of the [[Hermann grid illusion]].
  
 
==Description==
 
==Description==
[[Image:Ehrenstein2.gif|thumb|right|180px|Ehrenstein illusion.]]
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The classic Ehrenstein illusion consists of a grid in which the lines at an intersection terminate a short distance away from the intersection. When looking at the illusion, the viewer tends to see a circle that is slightly brighter than the background. If the space at the intersetctions is imagined to be square, it can also be perceived that way.
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The classic Ehrenstein illusion consists of a grid in which the lines at an intersection terminate a short distance away from the intersection. When looking at the illusion, the viewer tends to see a circle that is slightly brighter than the background. If the space at the intersections is imagined to be square, it can also be perceived that way.
[[Image:Ehrenstein figure.svg|thumb|Illusion 3,Adding a circle (bottom) destroys the illusion of a bright central disk.]]
 
  
 
==Explanation==
 
==Explanation==
The "phantom edge phenomena" (seeing an outline that is not actually there) is due to what neuropsychologists call the "T-effect". Groups of neural cells see breaks in lines, and if given no further input, will assume that there is a figure in front of the lines. Scientists believe that this happens because the brain has been trained to view the break in lines as an object that could pose a potential threat. With lack of additional information, the brain errs on the side of safety and perceives the space as an object. The circle is the most simple and symmetrical object, so the mind usually sees a circle unless active effort is made to see an alternate shape.<ref>[http://www.blelb.ch/english/blelbspots/spot06/exspot06_en.htm#top "The Grid illusion of Spot 06"] The Visual Perception Lab. Retrieved October 4, 2007.</ref>
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The "phantom edge phenomena" (seeing an outline that is not actually there) is due to what [[neuropsychology|neuropsychologists]] call the "T-effect." Groups of neural cells see breaks in lines, and if given no further input, will assume that there is a figure in front of the lines.  
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Scientists believe that this happens because the [[brain]] has been trained to view the break in lines as an object that could pose a potential threat. With lack of additional information, the brain errs on the side of safety and perceives the space as an object. The circle is the most simple and symmetrical object, so the mind usually sees a circle unless active effort is made to see an alternate shape.<ref>[http://www.blelb.ch/english/blelbspots/spot06/exspot06_en.htm#top "The Grid illusion of Spot 06"] The Visual Perception Lab. Retrieved October 4, 2007.</ref>
  
 
==Applications==
 
==Applications==
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*Seckel, Al. "More Optical Illusions" October 2002. Carlton Books ISBN 1842224875
 
*Seckel, Al. "More Optical Illusions" October 2002. Carlton Books ISBN 1842224875
 
*Zakia, Richard D. "Perception and Imaging" December 2001. Focal Press. ISBN 024080466X
 
*Zakia, Richard D. "Perception and Imaging" December 2001. Focal Press. ISBN 024080466X
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{{Credits|Ehrenstein_illusion|115531411|}}

Revision as of 00:27, 11 November 2007

File:Ehrenstein2.gif
Ehrenstein illusion.

The Ehrenstein illusion is an optical illusion in which a circle appears at the end points of a series of lines. The Ehrenstein illusion is one of the most popular subjective contour illusions (illusions that create the impression of a shape even though a large portion of the contour is nonexistent.) A similar effect can be found in the Kanizsa triangle.

Illusion 3,Adding a circle (bottom) destroys the illusion of a bright central disk.

Discovery

The Ehrenstein illusion is named for German psychologist Walter Ehrenstein, who published his findings in 1941 in the German psychology journal Zeitschrift für Psychologie (150, 83-91). Ehrenstein published his findings as a modification of the Hermann grid illusion.

Description

The classic Ehrenstein illusion consists of a grid in which the lines at an intersection terminate a short distance away from the intersection. When looking at the illusion, the viewer tends to see a circle that is slightly brighter than the background. If the space at the intersections is imagined to be square, it can also be perceived that way.

Explanation

The "phantom edge phenomena" (seeing an outline that is not actually there) is due to what neuropsychologists call the "T-effect." Groups of neural cells see breaks in lines, and if given no further input, will assume that there is a figure in front of the lines.

Scientists believe that this happens because the brain has been trained to view the break in lines as an object that could pose a potential threat. With lack of additional information, the brain errs on the side of safety and perceives the space as an object. The circle is the most simple and symmetrical object, so the mind usually sees a circle unless active effort is made to see an alternate shape.[1]

Applications

Like many other perceptual illusions, the Ehrenstein illusion helps neuroscientists study how the brain processes visual information.

Notes

  1. "The Grid illusion of Spot 06" The Visual Perception Lab. Retrieved October 4, 2007.

References
ISBN links support NWE through referral fees

  • Ninio, Jacques. "The Science of Illusions" April 2001. Cornell University Press. ISBN 0801437709
  • Seckel, Al. "More Optical Illusions" October 2002. Carlton Books ISBN 1842224875
  • Zakia, Richard D. "Perception and Imaging" December 2001. Focal Press. ISBN 024080466X

Credits

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