Autokinetic effect

Last updated

The autokinetic effect (also referred to as autokinesis and the autokinetic illusion) is a phenomenon of visual perception in which a stationary, small point of light in an otherwise dark or featureless environment appears to move. [1] It was first recorded in 1799 by Alexander von Humboldt who observed illusory movement of a star in a dark sky, although he believed the movement was real. [2] It is presumed to occur because motion perception is always relative to some reference point, and in darkness or in a featureless environment there is no reference point, so the position of the single point is undefined. The direction of the movements does not appear to be correlated with involuntary eye movements, but may be determined by errors between eye position and that specified by efference copy of the movement signals sent to the extraocular muscles. Richard Gregory suggested that, with lack of peripheral information, eye movements which correct movements due to muscle fatigue are wrongly interpreted as movement of the perceived light. [3]

Contents

The amplitude of the movements is also undefined. Individual observers set their own frames of reference to judge amplitude (and possibly direction). Because the phenomenon is labile, it has been used to show the effects of social influence or suggestion on judgements. For example, if an observer who would otherwise say the light is moving one foot overhears another observer say the light is moving one yard, then the first observer will report that the light moved one yard. Discovery of the influence of suggestion on the autokinetic effect is often attributed to Sherif (1935), but it was recorded by Adams (1912), if not others.[ citation needed ]

Alexander von Humboldt observed the phenomenon in 1799 while looking at stars with the naked eye, but thought it was a real movement of the stars. Thus, he named them "Sternschwanken", meaning "swinging stars". It was not until 1857 that G. Schweitzer showed that it was a subjective phenomenon: several observers all simultaneously viewing the same star reported different directions of the movement. [4]

Many sightings of UFOs have been attributed to the autokinetic effect when looking at stars or planets.[ citation needed ]

The US Navy started studying autokinesis in 1945 in an attempt to explain vertigo experiences reported by pilots, but this "kinetic illusion" is now categorized as a vestibular-induced illusion: see vestibular system.

In literature

An evocative passage appears in H. G. Wells' novel The War of the Worlds . Although Wells ascribes the apparent "swimming" of the planet to telescope vibration and eye fatigue, it is likely that the autokinetic effect is also being described:

Looking through the telescope, one saw a circle of deep blue and the little round planet swimming in the field. It seemed such a little thing, so bright and small and still, faintly marked with transverse stripes, and slightly flattened from the perfect round. But so little it was, so silvery warm—a pin's-head of light! It was as if it quivered, but really this was the telescope vibrating with the activity of the clockwork that kept the planet in view. As I watched, the planet seemed to grow larger and smaller and to advance and recede, but that was simply that my eye was tired. Forty million miles it was from us—more than forty million miles of void. Few people realise the immensity of vacancy in which the dust of the material universe swims.

In aviation

The effect is well known as an illusion affecting pilots who fly at night. It is particularly dangerous for pilots flying in formation or rejoining a refueling tanker at night. Steps that can be taken to prevent or overcome the phenomenon include:

In combat

In his book documenting the opening stages of the second Gulf War from his position embedded with the 1st Marine Reconnaissance Battalion, Evan Wright documents an incident during which, at night in the Iraqi desert, the Marines observed the lights of a town approximately 40 kilometers away. These lights appeared to be moving and were suspected of belonging to a large combat force moving out to attack the marines. An airstrike was called in on the estimated position of the lights—estimated to be around 15 kilometers away—which resulted in no enemy assets being destroyed. It was later suggested by Major Shoup of the battalion that this misidentification was a result of autokinesis. In the HBO mini-series based on the book, this information was imparted to the viewer by the character of Sergeant Brad Colbert, who had correctly deduced that it was a town in both versions.

Night fighter and night bomber crews during the Second World War reported encounters with mysterious aerial phenomena, nicknamed foo fighters, which may have been caused by autokinesis or a similar effect.

Autostasis

The opposite effect of autokinesis is autostasis. [5] It is when a moving bright light in a dark sky appears stationary.

See also

Related Research Articles

<span class="mw-page-title-main">Persistence of vision</span> Optical illusion

Persistence of vision is the optical illusion that occurs when the visual perception of an object does not cease for some time after the rays of light proceeding from it have ceased to enter the eye. The illusion has also been described as "retinal persistence", "persistence of impressions", simply "persistence" and other variations. A very commonly given example of the phenomenon is the apparent fiery trail of a glowing coal or burning stick while it is whirled around in the dark.

<span class="mw-page-title-main">Optical illusion</span> Visually perceived images that differ from objective reality

In visual perception, an optical illusion is an illusion caused by the visual system and characterized by a visual percept that arguably appears to differ from reality. Illusions come in a wide variety; their categorization is difficult because the underlying cause is often not clear but a classification proposed by Richard Gregory is useful as an orientation. According to that, there are three main classes: physical, physiological, and cognitive illusions, and in each class there are four kinds: Ambiguities, distortions, paradoxes, and fictions. A classical example for a physical distortion would be the apparent bending of a stick half immersed in water; an example for a physiological paradox is the motion aftereffect. An example for a physiological fiction is an afterimage. Three typical cognitive distortions are the Ponzo, Poggendorff, and Müller-Lyer illusion. Physical illusions are caused by the physical environment, e.g. by the optical properties of water. Physiological illusions arise in the eye or the visual pathway, e.g. from the effects of excessive stimulation of a specific receptor type. Cognitive visual illusions are the result of unconscious inferences and are perhaps those most widely known.

A tactile illusion is an illusion that affects the sense of touch. Some tactile illusions require active touch, whereas others can be evoked passively. In recent years, a growing interest among perceptual researchers has led to the discovery of new tactile illusions and to the celebration of tactile illusions in the popular science press. Some tactile illusions are analogous to visual and auditory illusions, suggesting that these sensory systems may process information in similar ways; other tactile illusions don't have obvious visual or auditory analogs.

Gestalt psychology, gestaltism, or configurationism is a school of psychology and a theory of perception that emphasises the processing of entire patterns and configurations, and not merely individual components. It emerged in the early twentieth century in Austria and Germany as a rejection of basic principles of Wilhelm Wundt's and Edward Titchener's elementalist and structuralist psychology.

<span class="mw-page-title-main">Beta movement</span>

The term beta movement is used for the optical illusion of apparent motion in which the very short projection of one figure and a subsequent very short projection of a more or less similar figure in a different location are experienced as one figure moving.

<span class="mw-page-title-main">Night sky</span> Appearance of the sky in a clear night

The night sky is the nighttime appearance of celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon.

<span class="mw-page-title-main">Ternus illusion</span>

The Ternus illusion, also commonly referred to as the Ternus Effect, is an illusion related to human visual perception involving apparent motion. In a simplified explanation of one form of the illusion, two discs, are shown side by side as the first frame in a sequence of three frames. Next a blank frame is presented for a very short, variable duration. In the final frame, two similar discs are then shown in a shifted position. Depending on various factors including the time intervals between frames as well as spacing and layout, observers perceive either element motion, in which L appears to move to R while C remains stationary or they report experiencing group motion, in which L and C appear to move together to C and R. Both element motion and group motion can be observed in animated examples to the right in Figures 1 and 2.

Entoptic phenomena are visual effects whose source is within the human eye itself.

Closed-eye hallucinations and closed-eye visualizations (CEV) are hallucinations that occur when one's eyes are closed or when one is in a darkened room. They should not be confused with phosphenes, perceived light and shapes when pressure is applied to the eye's retina, or some other non-visual external cause stimulates the eye. Some people report CEV under the influence of psychedelics; these are reportedly of a different nature than the "open-eye" hallucinations of the same compounds. Similar hallucinations that occur due to loss of vision are called "visual release hallucinations".

<span class="mw-page-title-main">Motion aftereffect</span> Optical illusion

The motion aftereffect (MAE) is a visual illusion experienced after viewing a moving visual stimulus for a time with stationary eyes, and then fixating a stationary stimulus. The stationary stimulus appears to move in the opposite direction to the original stimulus. The motion aftereffect is believed to be the result of motion adaptation.

<span class="mw-page-title-main">Sensory illusions in aviation</span> Misjudgment of true orientation by pilots

Human senses are not naturally geared for the in-flight environment. Pilots may experience disorientation and loss of perspective, creating illusions that range from false horizons to sensory conflict with instrument readings or the misjudging of altitude over water.

The kappa effect or perceptual time dilation is a temporal perceptual illusion that can arise when observers judge the elapsed time between sensory stimuli applied sequentially at different locations. In perceiving a sequence of consecutive stimuli, subjects tend to overestimate the elapsed time between two successive stimuli when the distance between the stimuli is sufficiently large, and to underestimate the elapsed time when the distance is sufficiently small.

Identifying unidentified flying objects (UFOs) is a difficult task due to the normally poor quality of the evidence provided by those who report sighting the unknown object. Observations and subsequent reporting are often made by those untrained in astronomy, atmospheric phenomena, aeronautics, physics, and perception. Nevertheless, most officially investigated UFO sightings, such as from the U.S. Air Force's Project Blue Book, have been identified as being due to honest misidentifications of natural phenomena, aircraft, or other prosaic explanations. In early U.S. Air Force attempts to explain UFO sightings, unexplained sightings routinely numbered over one in five reports. However, in early 1953, right after the CIA's Robertson Panel, percentages of unexplained sightings dropped precipitously, usually being only a few percent in any given year. When Project Blue Book closed down in 1970, only 6% of all cases were classified as being truly unidentified.

Within computer technology, the gaze-contingency paradigm is a general term for techniques allowing a computer screen display to change in function depending on where the viewer is looking. Gaze-contingent techniques are part of the eye movement field of study in psychology.

<span class="mw-page-title-main">Motion-induced blindness</span> Optical illusion

Motion Induced Blindness (MIB), also known as Bonneh's illusion is a visual illusion in which a large, continuously moving pattern erases from perception some small, continuously presented, stationary dots when one looks steadily at the center of the display. It was discovered by Bonneh, Cooperman, and Sagi (2001), who used a swarm of blue dots moving on a virtual sphere as the larger pattern and three small yellow dots as the smaller pattern. They found that after about 10 seconds, one or more of the dots disappeared for brief, random times.

<span class="mw-page-title-main">Illusions of self-motion</span> Misperception of ones location or movement

Illusions of self-motion occur when one perceives bodily motion despite no movement taking place. One can experience illusory movements of the whole body or of individual body parts, such as arms or legs.

<span class="mw-page-title-main">Broken escalator phenomenon</span> Illusion when stepping onto a broken escalator

The broken escalator phenomenon is the sensation of losing balance, confusion or dizziness reported by some people when stepping onto an escalator which is not working. It is said that there is a brief, odd sensation of imbalance, despite full awareness that the escalator is not going to move.

<span class="mw-page-title-main">Hans Wallach</span>

Hans Wallach was a German-American experimental psychologist whose research focused on perception and learning. Although he was trained in the Gestalt psychology tradition, much of his later work explored the adaptability of perceptual systems based on the perceiver's experience, whereas most Gestalt theorists emphasized inherent qualities of stimuli and downplayed the role of experience. Wallach's studies of achromatic surface color laid the groundwork for subsequent theories of lightness constancy, and his work on sound localization elucidated the perceptual processing that underlies stereophonic sound. He was a member of the National Academy of Sciences, a Guggenheim Fellow, and recipient of the Howard Crosby Warren Medal of the Society of Experimental Psychologists.

Fred W. Mast is a full professor of Psychology at the University of Bern in Switzerland, specialized in mental imagery, sensorimotor processing, and visual perception. He directs the Cognitive Psychology, Perception, and Research Methods Section at the Department of Psychology of the University of Bern.

Muzafer Sherif was a Turkish-American social psychologist. He helped develop social judgment theory and realistic conflict theory.

References

  1. ↑ Levy, John (1972). "Autokinetic illusion: A systematic review of theories, measures, and independent variables". Psychological Bulletin. 78 (6): 457–474. doi:10.1037/h0033614. PMID   4566651.
  2. ↑ von Humboldt, Alexander (1850). "Voyage aux regions équinoctiaux". Kosmos. 3: 73–74.
  3. ↑ Gregory, R. L. (1977). Eye and Brain: The Psychology of Seeing (Third ed.). London: Weidenfeld & Nicolson. p. 105. ISBN   0-297-77303-8.
  4. ↑ Adams, H. F. (1912). Autokinetic sensations. The Psychological Monographs, 14(2), i–44. doi:10.1037/h0093066
  5. ↑ Wertheimer, Michael (1968). "A Case of "Autostasis" or Reverse Autokinesis". Perceptual and Motor Skills. 26 (2): 417–418. doi:10.2466/pms.1968.26.2.417. PMID   5654860. S2CID   39932855.

Bibliography

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.