Illusory motion
Encyclopedia
The term illusory motion, also known as motion illusion, is used to define the appearance of movement in a static image.
This is an optical illusion
in which a static image appears to be moving due to the cognitive
effects of interacting color contrasts and shape position.
Another type of motion illusion that causes an optical illusion is when a moving object appears to be moving in a path other than what is perceived by the brain. An example of this can be demonstrated by placing a colored filter over ones eye of the observer, and swinging a ball back and forth in front of them. To the observer the ball appears to be swinging in a circular motion.
It appears that the sky is falling,
while the reality is that the ocean is rising.
Illusory motion can occur in different circumstances.
.)
This theory has however received a strong counter-argument. A simple demonstration to disprove the idea is to view an apparent counter-rotation (that of a rotating drum) in mirror image. Subjective
reports reveal that the counter-rotation appears in only one of the images (either the real or mirrored image when both are viewed simultaneously.)
Another explanation is that after images from the retina (the McCullough effect) cause a moire that is hard to identify.
band Animal Collective
used an optical illusion of this type on the cover of their award-winning 2009-album Merriweather Post Pavilion
.
This is an optical illusion
Optical illusion
An optical illusion is characterized by visually perceived images that differ from objective reality. The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source...
in which a static image appears to be moving due to the cognitive
Cognition
In science, cognition refers to mental processes. These processes include attention, remembering, producing and understanding language, solving problems, and making decisions. Cognition is studied in various disciplines such as psychology, philosophy, linguistics, and computer science...
effects of interacting color contrasts and shape position.
Another type of motion illusion that causes an optical illusion is when a moving object appears to be moving in a path other than what is perceived by the brain. An example of this can be demonstrated by placing a colored filter over ones eye of the observer, and swinging a ball back and forth in front of them. To the observer the ball appears to be swinging in a circular motion.
Occurrences
Theoretical example with the Illusion of motion:It appears that the sky is falling,
while the reality is that the ocean is rising.
Illusory motion can occur in different circumstances.
- Stroboscopic images - Where a series of static images are viewed in sequence at a high enough rate that the static images appear blend into a continuous motion. An example is a motion picture.
- Optical art (Op art.) - Where artists use simple black and white patterns that create vivid illusions of motion, known as optical flowOptical flowOptical flow or optic flow is the pattern of apparent motion of objects, surfaces, and edges in a visual scene caused by the relative motion between an observer and the scene. The concept of optical flow was first studied in the 1940s and ultimately published by American psychologist James J....
.
Stroboscopic images
Rotating objects can appear stationary under strobe light, also they can appear to be counter rotating. This second effect can occur in daylight, such as the apparent counter-rotation of wheels. Because of the illusion of counter rotation in constant light, it is reasonable to assume that the eye views the world in a series of still images, and therefore the counter-rotation is a result of under-sampling (aliasingAliasing
In signal processing and related disciplines, aliasing refers to an effect that causes different signals to become indistinguishable when sampled...
.)
This theory has however received a strong counter-argument. A simple demonstration to disprove the idea is to view an apparent counter-rotation (that of a rotating drum) in mirror image. Subjective
Subjectivity
Subjectivity refers to the subject and his or her perspective, feelings, beliefs, and desires. In philosophy, the term is usually contrasted with objectivity.-Qualia:...
reports reveal that the counter-rotation appears in only one of the images (either the real or mirrored image when both are viewed simultaneously.)
Optical art
Apparent motion in optical art has been suggested to be caused by the difference in neural signals between black and white parts of an image. While white parts may produce and 'on - off' signal, the black parts produce an 'off - on' signal. This means for a black part and a white part presented simultaneously, the 'on' part of the signal is separated in time, possibly resulting in the stimulation of motion detectors.Another explanation is that after images from the retina (the McCullough effect) cause a moire that is hard to identify.
In popular culture
The American Indie RockIndie rock
Indie rock is a genre of alternative rock that originated in the United Kingdom and the United States in the 1980s. Indie rock is extremely diverse, with sub-genres that include lo-fi, post-rock, math rock, indie pop, dream pop, noise rock, space rock, sadcore, riot grrrl and emo, among others...
band Animal Collective
Animal Collective
Animal Collective is an experimental psychedelic band originally from Baltimore, Maryland, currently based in New York City. Animal Collective consists of Avey Tare , Panda Bear , Deakin , and Geologist...
used an optical illusion of this type on the cover of their award-winning 2009-album Merriweather Post Pavilion
Merriweather Post Pavilion (album)
Merriweather Post Pavilion is the eighth studio album by American indie rock group Animal Collective, released in January 2009 on Domino Records. The album is named after the Columbia, Maryland venue, Merriweather Post Pavilion. At nearly 55 minutes in length, the album is the group's longest since...
.