The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and Darkness
Pupil diameters were recorded with an eye-tracker while participants observed cruciform patterns of gray-scale gradients that evoked illusions of enhanced brightness ( glare ) or of enhanced darkness. The illusions were either presented as static images or as dynamic animations which initially appea...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
SAGE Publishing
2017-08-01
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| Series: | i-Perception |
| Online Access: | https://doi.org/10.1177/2041669517717754 |
| _version_ | 1819088609233338368 |
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| author | Daniele Zavagno Luca Tommasi Bruno Laeng |
| author_facet | Daniele Zavagno Luca Tommasi Bruno Laeng |
| author_sort | Daniele Zavagno |
| collection | DOAJ |
| description | Pupil diameters were recorded with an eye-tracker while participants observed cruciform patterns of gray-scale gradients that evoked illusions of enhanced brightness ( glare ) or of enhanced darkness. The illusions were either presented as static images or as dynamic animations which initially appeared as a pattern of filled squares that—in a few seconds—gradually changed into gradients until the patterns were identical to the static ones. Gradients could either converge toward the center, resulting in a central region of enhanced, illusory, brightness or darkness, or oriented toward each side of the screen, resulting in the perception of a peripheral ring of illusory brightness or darkness. It was found that pupil responses to these illusions matched both the direction and intensity of perceived changes in light: Glare stimuli resulted in pupil constrictions, and darkness stimuli evoked dilations of the pupils. A second experiment found that gradients of brightness were most effective in constricting the pupils than isoluminant step-luminance, local, variations in luminance. This set of findings suggest that the eye strategically adjusts to reflect in a predictive manner, given that these brightness illusions only suggest a change in luminance when none has occurred, the content within brightness maps of the visual scene. |
| first_indexed | 2024-12-21T21:54:45Z |
| format | Article |
| id | doaj.art-afcd9f1fd4564112b312b8268a911d7f |
| institution | Directory Open Access Journal |
| issn | 2041-6695 |
| language | English |
| last_indexed | 2024-12-21T21:54:45Z |
| publishDate | 2017-08-01 |
| publisher | SAGE Publishing |
| record_format | Article |
| series | i-Perception |
| spelling | doaj.art-afcd9f1fd4564112b312b8268a911d7f2022-12-21T18:49:00ZengSAGE Publishingi-Perception2041-66952017-08-01810.1177/2041669517717754The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and DarknessDaniele ZavagnoLuca TommasiBruno LaengPupil diameters were recorded with an eye-tracker while participants observed cruciform patterns of gray-scale gradients that evoked illusions of enhanced brightness ( glare ) or of enhanced darkness. The illusions were either presented as static images or as dynamic animations which initially appeared as a pattern of filled squares that—in a few seconds—gradually changed into gradients until the patterns were identical to the static ones. Gradients could either converge toward the center, resulting in a central region of enhanced, illusory, brightness or darkness, or oriented toward each side of the screen, resulting in the perception of a peripheral ring of illusory brightness or darkness. It was found that pupil responses to these illusions matched both the direction and intensity of perceived changes in light: Glare stimuli resulted in pupil constrictions, and darkness stimuli evoked dilations of the pupils. A second experiment found that gradients of brightness were most effective in constricting the pupils than isoluminant step-luminance, local, variations in luminance. This set of findings suggest that the eye strategically adjusts to reflect in a predictive manner, given that these brightness illusions only suggest a change in luminance when none has occurred, the content within brightness maps of the visual scene.https://doi.org/10.1177/2041669517717754 |
| spellingShingle | Daniele Zavagno Luca Tommasi Bruno Laeng The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and Darkness i-Perception |
| title | The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and Darkness |
| title_full | The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and Darkness |
| title_fullStr | The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and Darkness |
| title_full_unstemmed | The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and Darkness |
| title_short | The Eye Pupil’s Response to Static and Dynamic Illusions of Luminosity and Darkness |
| title_sort | eye pupil s response to static and dynamic illusions of luminosity and darkness |
| url | https://doi.org/10.1177/2041669517717754 |
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