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Monocular Rivalry
Monocular rivalry is a phenomenon of human visual perception that occurs when two different images are optically superimposed. During prolonged viewing, one image becomes clearer than the other for a few moments, then the other image becomes clearer than the first for a few moments. These alternations in clarity continue at random for as long as one looks. Occasionally one image will become exclusively visible and the other image invisible. In the demonstration, one image is a green grating and the other is a red grating. During prolonged inspection, the viewer can see the green grating as clearer than the red grating for a few moments, then the reverse. Occasionally the green grating will be all that is visible and occasionally the red grating will be all that is visible. Occasionally, at transitions, one will briefly see irregular composites of the two gratings (such as the red and green gratings superimposed but with one or two bars of the green grating invisible). Monocular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proceedings Of The National Academy Of Sciences Of The United States Of America
''Proceedings of the National Academy of Sciences of the United States of America'' (often abbreviated ''PNAS'' or ''PNAS USA'') is a peer-reviewed multidisciplinary scientific journal. It is the official journal of the National Academy of Sciences, published since 1915, and publishes original research, scientific reviews, commentaries, and letters. According to ''Journal Citation Reports'', the journal has a 2022 impact factor of 9.4. ''PNAS'' is the second most cited scientific journal, with more than 1.9 million cumulative citations from 2008 to 2018. In the past, ''PNAS'' has been described variously as "prestigious", "sedate", "renowned" and "high impact". ''PNAS'' is a delayed open-access journal, with an embargo period of six months that can be bypassed for an author fee ( hybrid open access). Since September 2017, open access articles are published under a Creative Commons license. Since January 2019, ''PNAS'' has been online-only, although print issues are available ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perception
Perception () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous system, which in turn result from physical or chemical stimulation of the sensory system.Goldstein (2009) pp. 5–7 Vision involves light striking the retina of the eye; smell is mediated by odor molecules; and hearing involves pressure waves. Perception is not only the passive receipt of these signals, but it is also shaped by the recipient's learning, memory, expectation, and attention. Gregory, Richard. "Perception" in Gregory, Zangwill (1987) pp. 598–601. Sensory input is a process that transforms this low-level information to higher-level information (e.g., extracts shapes for object recognition). The following process connects a person's concepts and expectations (or knowledge) with restorative and selective mechanisms, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multistable Perception
Multistable perception (or bistable perception) is a perceptual phenomenon in which an observer experiences an unpredictable sequence of spontaneous subjective changes. While usually associated with visual perception (a form of optical illusion), multistable perception can also be experienced with auditory and olfactory percepts. Classification Perceptual multistability can be evoked by visual patterns that are too ambiguous for the human visual system to definitively and uniquely interpret. Familiar examples include the Necker cube, Schroeder staircase, structure from motion, monocular rivalry, and binocular rivalry, but many more visually ambiguous patterns are known. Because most of these images lead to an alternation between two mutually exclusive perceptual states, they are sometimes also referred to as bistable perception. Auditory and olfactory examples can occur when there are conflicting, and so rival, inputs into the two ears or two nostrils. Characteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motion-induced Interocular Suppression
Motion-induced interocular suppression is a phenomenon in which when one eye is presented with a constantly moving visual pattern while the other eye is shown a stationary image, the stationary image is suppressed from awareness for long periods of time.Mendoza, D. and Chaudhuri, A. (2007) Properties of prolonged interocular suppression of awareness. Presented at the 11th Annual Conference of the Association for the Scientific Study of Consciousness, Las Vegas, USA, 2007. The duration of this motion-induced interocular suppression is comparable to that of continuous flash suppression; thus, the two methods can be used alternatively. The duration of suppression in both methods is maximized if the image being suppressed has low luminance contrast or a low spatial frequency In mathematics, physics, and engineering, spatial frequency is a characteristic of any structure that is periodic across position in space. The spatial frequency is a measure of how often sinusoidal componen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubin Vase
The Rubin vase (sometimes known as Rubin's vase, the Rubin face or the figure–ground vase) is a famous example of ambiguous or bi-stable (i.e., reversing) two-dimensional forms developed around 1915 by the Danish psychologist Edgar Rubin. The depicted version of Rubin's vase can be seen as the black profiles of two people looking towards each other or as a white vase, but not both. Another example of a bistable figure Rubin included in his Danish-language, two-volume book was the Maltese cross. Rubin presented in his doctoral thesis (1915) a detailed description of the visual figure-ground relationship, an outgrowth of the visual perception and memory work in the laboratory of his mentor, Georg Elias Müller. One element of Rubin's research may be summarized in the fundamental principle, "When two fields have a common border, and one is seen as figure and the other as ground, the immediate perceptual experience is characterized by a shaping effect which emerges from the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Necker Cube
The Necker cube is an optical illusion that was first published as a rhomboid in 1832 by Swiss crystallographer Louis Albert Necker. It is a simple wire-frame, two dimensional drawing of a cube with no visual cues as to its orientation, so it can be interpreted to have either the lower-left or the upper-right square as its front side. Ambiguity The Necker cube is an ambiguous drawing. Each part of the picture is ambiguous by itself, yet the human visual system picks an interpretation of each part that makes the whole consistent. The Necker cube is sometimes used to test computer models of the human visual system to see whether they can arrive at consistent interpretations of the image the same way humans do. Humans do not usually see an inconsistent interpretation of the cube. A cube whose edges cross in an inconsistent way is an example of an impossible object, specifically an impossible cube. With the cube on the left, most people see the lower-left face as being in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multistable Perception
Multistable perception (or bistable perception) is a perceptual phenomenon in which an observer experiences an unpredictable sequence of spontaneous subjective changes. While usually associated with visual perception (a form of optical illusion), multistable perception can also be experienced with auditory and olfactory percepts. Classification Perceptual multistability can be evoked by visual patterns that are too ambiguous for the human visual system to definitively and uniquely interpret. Familiar examples include the Necker cube, Schroeder staircase, structure from motion, monocular rivalry, and binocular rivalry, but many more visually ambiguous patterns are known. Because most of these images lead to an alternation between two mutually exclusive perceptual states, they are sometimes also referred to as bistable perception. Auditory and olfactory examples can occur when there are conflicting, and so rival, inputs into the two ears or two nostrils. Characteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periodic Function
A periodic function, also called a periodic waveform (or simply periodic wave), is a function that repeats its values at regular intervals or periods. The repeatable part of the function or waveform is called a ''cycle''. For example, the trigonometric functions, which repeat at intervals of 2\pi radians, are periodic functions. Periodic functions are used throughout science to describe oscillations, waves, and other phenomena that exhibit periodicity. Any function that is not periodic is called ''aperiodic''. Definition A function is said to be periodic if, for some nonzero constant , it is the case that :f(x+P) = f(x) for all values of in the domain. A nonzero constant for which this is the case is called a period of the function. If there exists a least positive constant with this property, it is called the fundamental period (also primitive period, basic period, or prime period.) Often, "the" period of a function is used to mean its fundamental period. A funct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Perception
Visual perception is the ability to detect light and use it to form an image of the surrounding Biophysical environment, environment. Photodetection without image formation is classified as ''light sensing''. In most vertebrates, visual perception can be enabled by photopic vision (daytime vision) or scotopic vision (night vision), with most vertebrates having both. Visual perception detects light (photons) in the visible spectrum reflected by objects in the environment or emitted by light sources. The light, visible range of light is defined by what is readily perceptible to humans, though the visual perception of non-humans often extends beyond the visual spectrum. The resulting perception is also known as vision, sight, or eyesight (adjectives ''visual'', ''optical'', and ''ocular'', respectively). The various physiological components involved in vision are referred to collectively as the visual system, and are the focus of much research in linguistics, psychology, cognitive s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Adaptation
Neural adaptation or sensory adaptation is a gradual decrease 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 a hand is rested on a table, the table's surface is immediately felt against the skin. Subsequently, however, the sensation of the table surface against the skin gradually diminishes until it is virtually unnoticeable. The sensory neurons that initially respond are no longer stimulated to respond; this is an example of neural adaptation. All sensory and neural systems have a form of adaptation to constantly detect changes in the environment. Neural receptor cells that process and receive stimulation go through constant changes for mammals and other living organisms to sense vital changes in their environment. Some key players in several neural systems include Ca2+ions (see Calcium in biology) that send negative feedback in second messenger pathways that allow the neural r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afterimage
An afterimage, or after-image, is an image that continues to appear in the eyes after a period of exposure to the original image. An afterimage may be a normal phenomenon (physiological afterimage) or may be pathological (palinopsia). Illusory palinopsia may be a pathological exaggeration of physiological afterimages. Afterimages occur because Photochemistry, photochemical activity in the retina continues even when the eyes are no longer experiencing the original stimulus. The remainder of this article refers to physiological afterimages. A common physiological afterimage is the dim area that seems to float before one's human eye, eyes after briefly looking into a light source, such as a camera flash. Palinopsia is a common symptom of visual snow. Negative afterimages Negative image, Negative afterimages are generated in the retina but may be modified like other retinal signals by neural adaptation of the retinal ganglion cells that carry signals from the retina of the eye to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
