Contingent perceptual aftereffect

Contingent aftereffects are studied in human perception and can be defined as illusory percepts that are apparent on a test stimulus after exposure to an induction stimulus for an extended period. Contingent aftereffects can be contrasted with simple aftereffects, the later requiring no test stimulus for the illusion/mis-perception to be apparent. Contingent aftereffects have been studied in different perceptual domains. For instance, visual contingent aftereffects, auditory contingent aftereffects and haptic contingent aftereffects have all been discovered.

An example of a visual contingent aftereffect is the McCollough effect. The McCollough Effect is one of a family of contingent aftereffects related to the processing of color and orientation. One can induce the aftereffect by exposure to a magenta and black vertical grating alternating with a green and black horizontal grating. After a few minutes of induction (5 or more is best), followed by a break of a few minutes, black-and-white vertical and horizontal gratings will appear colored. The verticals will look green and horizontals pink in the example given. Therefore, the illusory color apparent on the test fields is contingent on the orientation of the lines in that test field. Furthermore, the orientation-colour contingencies present in the illusion are the reverse of those present in the adapting stimulus (i.e., the magenta-vertical and green-horizontal adaptation gratings produced illusory magenta on the horizontal test gratings and illusory green on the vertical test grating). The illusion will reverse if one rotates one's head 90°. This is because the effect is retino-topic, that is, the effect is dependent on the orientation of the test lines on the retina.

There are also color-contingent motion aftereffects^[1], and other varieties of these phenomena.

See also

• Optical illusion
• Visual perception

References

1. ^ Favreau O.E., Emerson V.F., Corballis M.C.

• Favreau O.E., Emerson V.F., Corballis M.C. (1972) Motion Perception: A Color-Contingent Aftereffect. Science, 7, 78-79.

This cognitive psychology-related article is a stub. You can help Wikipedia by expanding it.v · Categories: Optical illusions Cognitive psychology stubs Wikimedia Foundation. 2010. Игры ⚽ Поможем написать реферат Gammage Warp (magazine) Look at other dictionaries: contingent perceptual aftereffect —    see contingent aftereffect …   Dictionary of Hallucinations contingent aftereffect —    Also known as contingent perceptual aftereffect. Both terms are used to denote a type of aftereffect that is dependent on (i.e. contingent with) the orientation of the perceived object with respect to the retina. An example is the * McCollough …   Dictionary of Hallucinations aftereffect —    Also known as aftersensation and perceptual aftereffect. All three terms refer to the illusory visual perception that may follow prolonged exposure to a particular visual stimulus. As a rule, aftereffects present themselves in the inverted… …   Dictionary of Hallucinations Optical illusion — This article is about visual perception. For the Time Requiem album, see Optical Illusion (album). An optical illusion. The square A is exactly the same shade of gray as square B. See checker shadow illusion. An optical illusion (also called a… …   Wikipedia Neural adaptation — or sensory adaptation is a change over time in the responsiveness of the sensory system to a constant stimulus. It is usually experienced as a change in the stimulus. For example, if one rests one s hand on a table, one immediately feels the… …   Wikipedia Celeste McCollough — Celeste McCollough, known since about 1996 as Celeste McCollough Howard is an American scientist who conducts research in human visual perception. She is famous for discovering, in 1965, the first contingent aftereffect, known soon after as the… …   Wikipedia 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”