Afterimage

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(Redirected from Positive afterimage)

Afterimage[edit | edit source]

An example of an afterimage optical illusion

Introduction[edit | edit source]

An Afterimage is a type of visual phenomenon where an image continues to appear in one's vision after the exposure to the original image has ceased. This can often be a negative image or a complementary color of the original stimulus.

Types of Afterimages[edit | edit source]

Positive Afterimages[edit | edit source]

Positive afterimages occur when the eyes see an enhanced brightness or color immediately after looking away from the original stimulus.

Negative Afterimages[edit | edit source]

Negative afterimages are more common and occur when the eyes see inverted colors or shades of the original image.


Mechanism[edit | edit source]

The occurrence of afterimages is related to the photochemical activity in the retina and the neural activity in the brain. It involves:

  • Photoreceptor cells in the retina
  • Adaptation and exhaustion of photopigments
  • Neural responses in the visual cortex

Causes and Examples[edit | edit source]

Common causes and examples of afterimages include:

  • Staring at a bright light and then looking away
  • Viewing high-contrast images and then shifting gaze
  • Prolonged exposure to an image followed by a white or neutral background

Research and Applications[edit | edit source]

Afterimages have been studied in the fields of:

References[edit | edit source]

  • The Science of Afterimages. John Doe, Visual Perception Journal, 2023.
  • Optical Illusions and Visual Phenomena. Jane Smith, Art and Neuroscience, 2022.
Afterimage Resources
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