Perception

Perception (from the Template:Wiki perceptio, percipio) is the organization, identification and interpretation of Template:Wiki information in order to represent and understand the Template:Wiki.

All perception involves signals in the Template:Wiki, which in turn result from Template:Wiki Template:Wiki of the sense organs.

For example, Template:Wiki involves light striking the Template:Wiki of the Template:Wiki, Template:Wiki is mediated by Template:Wiki Template:Wiki and Template:Wiki involves pressure waves.

Perception is not the passive receipt of these signals, but can be shaped by Template:Wiki, memory and expectation.

Perception involves these "top-down" effects as well as the "bottom-up" process of processing Template:Wiki input.

The "bottom-up" processing is basically low-level Template:Wiki that's used to build up higher-level information (i.e. - shapes for object recognition).

The "top-down" processing refers to a person's Template:Wiki and expectations (knowledge) that influence perception. Perception depends on complex functions of the Template:Wiki, but subjectively seems mostly effortless because this processing happens outside conscious awareness.

Since the rise of experimental Template:Wiki in the late 19th Century, Template:Wiki's understanding of perception has progressed by combining a variety of techniques. Template:Wiki measures the effect on perception of varying the physical qualities of the input. Template:Wiki Template:Wiki studies the Template:Wiki mechanisms underlying perception. Template:Wiki systems can also be studied computationally, in terms of the information they process. Template:Wiki issues in philosophy include the extent to which Template:Wiki qualities such as Template:Wiki, Template:Wiki or colors exist in objective reality rather than the mind of the Template:Wiki.

Although the senses were traditionally viewed as passive Template:Wiki, the study of Template:Wiki and Template:Wiki images has demonstrated that the Template:Wiki's Template:Wiki systems actively and pre-consciously attempt to make sense of their input. There is still active debate about the extent to which perception is an active process of Template:Wiki testing, analogous to Template:Wiki, or whether Template:Wiki Template:Wiki information is rich enough to make this process unnecessary.

The Template:Wiki of the Template:Wiki enable Template:Wiki to see the world around them as Template:Wiki, even though the Template:Wiki information may be incomplete and rapidly varying. Template:Wiki and Template:Wiki Template:Wiki are structured in a modular way, with different areas processing different kinds of sensory Template:Wiki. Some of these modules take the form of Template:Wiki maps, mapping some aspect of the world across part of the Template:Wiki's surface. These different modules are interconnected and influence each other. For instance, the Template:Wiki is strongly influenced by its Template:Wiki.

 Process and Template:Wiki

The process of perception begins with an object in the Template:Wiki world, termed the distal Template:Wiki or distal object. By means of light, sound or another physical process, the object stimulates the Template:Wiki's Template:Wiki. These Template:Wiki transform the input energy into neural activity—a process called transduction. This raw pattern of neural activity is called the Template:Wiki. These neural signals are transmitted to the Template:Wiki and processed. The resulting mental re-creation of the distal Template:Wiki is the Template:Wiki. Perception is sometimes described as the process of constructing mental Template:Wiki of distal Template:Wiki using the information available in Template:Wiki.

An example would be a person looking at a shoe. The shoe itself is the distal Template:Wiki. When light from the shoe enters a person's eye and stimulates their Template:Wiki, that Template:Wiki is the Template:Wiki. The image of the shoe reconstructed by the brain of the person is the Template:Wiki. Another example would be a telephone ringing. The ringing of the telephone is the distal Template:Wiki. The sound stimulating a person's Template:Wiki Template:Wiki is the Template:Wiki, and the brain's interpretation of this as the ringing of a telephone is the Template:Wiki. The different kinds of sensation such as warmth, sound, and Template:Wiki are called "sensory modalities".

Template:Wiki Template:Wiki has developed a model of perception. According to him people go through the following process to form opinions:.

    When a Template:Wiki encounters an unfamiliar target we are opened different informational cues and want to learn more about the target.
    In the second step we try to collect more Template:Wiki about the target. Gradually, we encounter some familiar cues which helps us categorize the target.
    At this stage the cues become less open and selective. We try to search for more cues that confirm the categorization of the target. At this stage we also actively ignore and even distort cues that violate our initial perceptions. Our perception becomes more selective and we finally paint a consistent picture of the target.

According to Alan Saks and Template:Wiki, there are three components to perception.

    The Template:Wiki, the person who becomes Template:Wiki about something and comes to a final understanding. There are 3 factors that can influence his or her perceptions: Template:Wiki, motivational state and finally emotional state. In different motivational or emotional states, the Template:Wiki will react to or Template:Wiki something in different ways. Also in different situations he or she might employ a "Template:Wiki defence" where they tend to "see what they want to see".
    The Target. This is the person who is being perceived or judged. "Template:Wiki or lack of information about a target leads to a greater need for interpretation and addition."
    The Situation also greatly influences perceptions because different situations may call for additional information about the target.

Template:Wiki are not necessarily translated into a Template:Wiki and rarely does a single Template:Wiki translate into a Template:Wiki. An Template:Wiki Template:Wiki may be translated into multiple Template:Wiki, experienced randomly, one at a time, in what is called "multistable perception". And the same Template:Wiki, or absence of them, may result in different Template:Wiki depending on subject’s Template:Wiki and previous Template:Wiki. Template:Wiki figures demonstrate that a single Template:Wiki can result in more than one Template:Wiki; for example the Rubin vase which can be interpreted either as a vase or as two faces. The Template:Wiki can bind sensations from multiple senses into a whole. A picture of a talking person on a television screen, for example, is bound to the sound of speech from speakers to form a Template:Wiki of a talking person. "Template:Wiki" is also a term used by Template:Wiki Bergson, Template:Wiki and Template:Wiki ] to define perception Template:Wiki from perceivers.
Perception and reality

In the case of visual perception, some people can actually see the Template:Wiki shift in their mind's eye. Others, who are not picture thinkers, may not necessarily Template:Wiki the 'shape-shifting' as their world changes. The 'Template:Wiki' nature has been shown by experiment: an Template:Wiki image has multiple interpretations on the Template:Wiki level.

This confusing Template:Wiki of perception is exploited in human technologies such as Template:Wiki, and also in Template:Wiki Template:Wiki, for example by Template:Wiki Peacock butterflies, whose wings bear eye markings that birds respond to as though they were the eyes of a dangerous predator.

There is also Template:Wiki that the Template:Wiki in some ways operates on a slight "delay", to allow Template:Wiki Template:Wiki from distant parts of the body to be integrated into simultaneous signals.[13]

Perception is one of the oldest fields in psychology. The oldest quantitative law in psychology is the Template:Wiki, which quantifies the relationship between the intensity of physical Template:Wiki and their Template:Wiki effects (for example, testing how much darker a Template:Wiki screen can get before the viewer actually notices). The study of perception gave rise to the Gestalt school of psychology, with its Template:Wiki on Template:Wiki approach.
Features
Constancy
 

Template:Wiki constancy is the ability of Template:Wiki to recognise the same object from widely varying sensory inputs. For example, Template:Wiki people can be recognised from views, such as frontal and profile, which form very different shapes on the Template:Wiki. A coin looked at face-on makes a circular image on the Template:Wiki, but when held at angle it makes an elliptical image. In normal perception these are recognised as a single three-dimensional object. Without this Template:Wiki process, an animal approaching from the distance would appear to gain in size. One kind of Template:Wiki constancy is Template:Wiki constancy: for example, a white piece of paper can be recognized as such under different colors and intensities of light.[17] Another example is roughness constancy: when a hand is drawn quickly across a surface, the Template:Wiki Template:Wiki are stimulated more intensely. The Template:Wiki compensates for this, so the Template:Wiki of contact does not affect the perceived roughness. Other constancies include melody, Template:Wiki, brightness and words. These constancies are not always total, but the variation in the Template:Wiki is much less than the variation in the physical Template:Wiki. The Template:Wiki of the Template:Wiki achieve Template:Wiki constancy in a variety of ways, each specialized for the kind of information being processed.
Grouping
 
Law of Closure. The human Template:Wiki tends to Template:Wiki complete shapes even if those forms are incomplete.

The Template:Wiki of grouping (or Template:Wiki laws of grouping) are a set of Template:Wiki in psychology, first proposed by Template:Wiki Template:Wiki to explain how humans naturally Template:Wiki objects as organized patterns and objects. Template:Wiki Template:Wiki argued that these Template:Wiki exist because the mind has an innate disposition to Template:Wiki patterns in the Template:Wiki based on certain Template:Wiki. These Template:Wiki are organized into six categories. The principle of proximity states that, all else being Template:Wiki, perception tends to group Template:Wiki that are close together as part of the same object, and Template:Wiki that are far apart as two separate objects. The principle of similarity states that, all else being Template:Wiki, perception lends itself to seeing Template:Wiki that Template:Wiki resemble each other as part of the same object, and Template:Wiki that are different as part of a different object. This allows for people to distinguish between adjacent and overlapping objects based on their visual Template:Wiki and resemblance. The principle of closure refers to the mind’s tendency to see complete figures or forms even if a picture is incomplete, partially hidden by other objects, or if part of the information needed to make a complete picture in our minds is missing. For example, if part of a shape’s border is missing people still tend to see the shape as completely enclosed by the border and ignore the gaps. The principle of good continuation makes sense of Template:Wiki that overlap: when there is an intersection between two or more objects, people tend to Template:Wiki each as a single uninterrupted object. The principle of common fate groups Template:Wiki together on the basis of their Template:Wiki. When visual elements are seen moving in the same direction at the same rate, perception associates the Template:Wiki as part of the same Template:Wiki. This allows people to make out moving objects even when other details, such as Template:Wiki or outline, are obscured. The principle of good form refers to the tendency to group together forms of similar shape, pattern, Template:Wiki, etc. Later research has identified additional grouping Template:Wiki.
Contrast effects

A common finding across many different kinds of perception is that the perceived qualities of an object can be affected by the qualities of context. If one object is extreme on some dimension, then neighboring objects are perceived as further away from that extreme. "Simultaneous contrast effect" is the term used when Template:Wiki are presented at the same time, whereas "successive contrast" applies when Template:Wiki are presented one after another.

The contrast effect was noted by the 17th Century philosopher Template:Wiki, who observed that lukewarm water can feel hot or cold, depending on whether the hand touching it was previously in hot or cold water. In the early 20th Century, Wilhelm Wundt identified contrast as a fundamental principle of perception, and since then the effect has been confirmed in many different areas. These effects shape not only visual qualities like Template:Wiki and brightness, but other kinds of perception, including how heavy an object feels.[27] One experiment found that thinking of the name "Template:Wiki" led to subjects rating a person as more Template:Wiki. Whether a piece of Template:Wiki is perceived as good or bad can depend on whether the Template:Wiki heard before it was unpleasant or pleasant. For the effect to work, the objects being compared need to be similar to each other: a television reporter can seem smaller when interviewing a tall basketball player, but not when standing next to a tall building.
Effect of experience
 

With experience, Template:Wiki can learn to make finer Template:Wiki Template:Wiki, and learn new kinds of categorization. Wine-tasting, the reading of X-ray images and Template:Wiki appreciation are applications of this process in the human sphere. Research has focused on the relation of this to other kinds of Template:Wiki, and whether it takes place in peripheral sensory systems or in the brain's processing of sense information.
Effect of motivation and expectation
 

A Template:Wiki set, also called Template:Wiki expectancy or just set is a predisposition to Template:Wiki things in a certain way. It is an example of how perception can be shaped by "top-down" Template:Wiki such as drives and expectations. Template:Wiki sets occur in all the different senses. They can be long term, such as a special sensitivity to hearing one's own name in a crowded room, or short term, as in the ease with which hungry people notice the Template:Wiki of food. A simple demonstration of the effect involved very brief presentations of non-words such as "sael". Subjects who were told to expect words about animals read it as "Template:Wiki", but others who were expecting boat-related words read it as "sail".

Sets can be created by motivation and so can result in people interpreting Template:Wiki figures so that they see what they want to see For instance, how someone perceives what unfolds during a sports game can be biased if they strongly support one of the teams. In one experiment, students were allocated to pleasant or unpleasant tasks by a Template:Wiki. They were told that either a number or a letter would flash on the screen to say whether they were going to Template:Wiki an orange juice drink or an unpleasant-tasting health drink. In fact, an Template:Wiki figure was flashed on screen, which could either be read as the letter B or the number 13. When the letters were associated with the pleasant task, subjects were more likely to Template:Wiki a letter B, and when letters were associated with the unpleasant task they tended to Template:Wiki a number 13

Template:Wiki set has been demonstrated in many Template:Wiki contexts. People who are primed to think of someone as "warm" are more likely to Template:Wiki a variety of positive Template:Wiki in them, than if the word "warm" is replaced by "cold". When someone has a reputation for being funny, an audience are more likely to find them amusing. Individual's Template:Wiki sets reflect their own personality traits. For example, people with an aggressive personality are quicker to correctly identify aggressive words or situations

One classic psychological experiment showed slower Template:Wiki times and less accurate answers when a deck of playing cards reversed the Template:Wiki of the suit symbol for some cards (e.g. red spades and black hearts).

Philosopher Andy Clark explains that perception, although it occurs quickly, is not simply a bottom-up process (where minute details are put together to form larger wholes). Instead, our Template:Wiki use what he calls Predictive coding. It starts with very broad constraints and expectations for the state of the world, and as expectations are met, it makes more detailed predictions (errors lead to new predictions, or Template:Wiki Template:Wiki). Clark says this research has various implications; not only can there be no completely "unbiased, unfiltered" perception, but this means that there is a great deal of feedback between perception and expectation (Template:Wiki experiences often shape our beliefs, but those perceptions were based on existing beliefs).
Theories
Perception as hypothesis-testing

Cognitive theories of perception assume there is a Template:Wiki of Template:Wiki. This (with reference to perception) is the claim that sensations are, by themselves, unable to provide a unique description of the world. " Sensations require 'enriching', which is the role of the mental model. A different type of Template:Wiki is the Template:Wiki Template:Wiki approach of James J. Gibson. Gibson rejected the assumption of a Template:Wiki of Template:Wiki by rejecting the notion that perception is based upon sensations – instead, he investigated what information is actually presented to the Template:Wiki. His Template:Wiki "assumes the existence of Template:Wiki, unbounded, and permanent stimulus-information in the ambient optic array. And it supposes that the visual system can explore and detect this information. The Template:Wiki is information-based, not sensation-based." He and the Template:Wiki who work within this Template:Wiki detailed how the world could be specified to a mobile, exploring Template:Wiki via the lawful projection of information about the world into energy arrays. Specification is a 1:1 mapping of some aspect of the world into a Template:Wiki array; given such a mapping, no enrichment is required and perception is direct perception.
Perception-in-action

An Template:Wiki understanding of perception derived from Gibson's early work is that of "perception-in-action", the notion that perception is a requisite property of animate action; that without perception action would be unguided, and without action perception would serve no Template:Wiki. Animate actions require both perception and Template:Wiki, and perception and Template:Wiki can be described as "two sides of the same coin, the coin is action". Gibson works from the assumption that singular entities, which he calls "invariants", already exist in the Template:Wiki world and that all that the perception process does is to home in upon them. A view known as constructivism (held by such philosophers as Ernst von Glasersfeld) regards the continual adjustment of perception and action to the Template:Wiki input as precisely what constitutes the "entity", which is therefore far from being invariant.

Glasersfeld considers an "invariant" as a target to be homed in upon, and a Template:Wiki necessity to allow an initial measure of understanding to be established prior to the updating that a statement aims to achieve. The invariant does not and need not represent an actuality, and Glasersfeld describes it as extremely unlikely that what is desired or feared by an Template:Wiki will never suffer change as time goes on. This Template:Wiki constructionist Template:Wiki thus allows for a needful evolutionary adjustment.

A Template:Wiki Template:Wiki of perception-in-action has been devised and investigated in many forms of controlled Template:Wiki, and has been described in many different Template:Wiki of Template:Wiki using the General Tau Template:Wiki. According to this Template:Wiki, tau information, or time-to-goal information is the fundamental 'Template:Wiki' in perception.
Evolutionary psychology and perception

Many philosophers, such as Jerry Fodor, write that the Template:Wiki of perception is knowledge, but evolutionary Template:Wiki hold that its primary Template:Wiki is to guide action. For example, they say, depth perception seems to have evolved not to help us know the distances to other objects but rather to help us move around in space. Evolutionary Template:Wiki say that animals from fiddler crabs to humans use eyesight for collision avoidance, suggesting that vision is basically for directing action, not providing knowledge.

Building and maintaining sense organs is metabolically expensive, so these Template:Wiki evolve only when they improve an organism's fitness. More than half the Template:Wiki is devoted to processing sensory information, and the Template:Wiki itself consumes roughly one-fourth of one's Template:Wiki resources, so the senses must provide exceptional benefits to fitness. Perception accurately mirrors the world; animals get useful, accurate information through their senses.

Scientists who study perception and sensation have long understood the human senses as adaptations. Depth perception consists of processing over half a dozen visual cues, each of which is based on a regularity of the physical world. Vision evolved to respond to the narrow range of Template:Wiki energy that is plentiful and that does not pass through objects. Sound waves provide useful information about the sources of and distances to objects, with larger animals making and hearing lower-frequency Template:Wiki and smaller animals making and hearing higher-frequency Template:Wiki. Template:Wiki and Template:Wiki respond to Template:Wiki in the Template:Wiki that were significant for fitness in the EEA. The sense of Template:Wiki is actually many senses, including pressure, heat, cold, tickle, and pain. Pain, while unpleasant, is adaptive. An important adaptation for senses is range shifting, by which the Template:Wiki becomes temporarily more or less sensitive to sensation. For example, one's eyes automatically adjust to dim or bright ambient light. Template:Wiki Template:Wiki of different Template:Wiki often coevolve, as is the case with the hearing of echolocating bats and that of the moths that have evolved to respond to the Template:Wiki that the bats make.

Evolutionary Template:Wiki claim that perception demonstrates the principle of modularity, with specialized mechanisms handling particular perception tasks. For example, people with damage to a particular part of the Template:Wiki suffer from the specific defect of not being able to recognize faces (prospagnosia). EP suggests that this indicates a so-called face-reading module.
Theories of visual perception

    Empirical theories of perception
    Anne Treisman's feature Template:Wiki Template:Wiki
    Interactive activation and competition
    Irving Biederman's recognition by components Template:Wiki

Physiology
 

A sensory system is a part of the Template:Wiki responsible for processing sensory information. A sensory system consists of sensory Template:Wiki, neural pathways, and parts of the Template:Wiki involved in sensory perception. Commonly recognized sensory systems are those for vision, hearing, somatic sensation (Template:Wiki), Template:Wiki and Template:Wiki (Template:Wiki). It has been suggested that the Template:Wiki is an overlooked sensory modlality. In short, senses are transducers from the physical world to the realm of the mind.

The receptive field is the specific part of the world to which a receptor Template:Wiki and receptor Template:Wiki respond. For instance, the part of the world an eye can see, is its receptive field; the light that each rod or cone can see, is its receptive field. Receptive fields have been identified for the visual system, Template:Wiki system and Template:Wiki system, so far.
Types
Of sound

Hearing (or audition) is the ability to Template:Wiki sound by detecting Template:Wiki. Frequencies capable of being heard by humans are called audio or sonic. The range is typically considered to be between 20 Hz and 20,000 Hz. Frequencies higher than audio are referred to as ultrasonic, while frequencies below audio are referred to as infrasonic. The Template:Wiki system includes the Template:Wiki and inner structures which produce neural signals in response to the sound. The primary Template:Wiki cortex, within the Template:Wiki lobe of the human Template:Wiki, is where Template:Wiki information arrives in the cerebral cortex.

Sound does not usually come from a single source: in Template:Wiki situations, Template:Wiki from multiple sources and directions are Template:Wiki as they arrive at the Template:Wiki. Hearing involves the computationally complex task of separating out the sources of interest, often estimating their distance and direction as well as identifying them.
Of speech

Though the phrase "I owe you" can be heard as three Template:Wiki words, a spectrogram reveals no clear boundaries.

Speech perception is the process by which the Template:Wiki of language are heard, interpreted and understood. Research in speech perception seeks to understand how human listeners recognize speech Template:Wiki and use this information to understand spoken language. The sound of a word can vary widely according to words around it and the tempo of the speech, as well as the physical Template:Wiki, accent and mood of the speaker. Listeners manage to Template:Wiki words across this wide range of different conditions. Another variation is that reverberation can make a large difference in sound between a word spoken from the far side of a room and the same word spoken up close. Experiments have shown that people automatically compensate for this effect when hearing speech.

The process of perceiving speech begins at the level of the sound within the Template:Wiki signal and the process of audition. After processing the initial Template:Wiki signal, speech Template:Wiki are further processed to extract acoustic cues and phonetic information. This speech information can then be used for higher-level language Template:Wiki, such as word recognition. Speech perception is not necessarily uni-directional. That is, higher-level language Template:Wiki connected with morphology, syntax, or semantics may interact with basic speech perception Template:Wiki to aid in recognition of speech Template:Wiki. It may be the case that it is not necessary and maybe even not possible for a listener to recognize phonemes before recognizing higher units, like words for example. In one experiment, Richard M. Warren replaced one phoneme of a word with a cough-like sound. His subjects restored the missing speech sound perceptually without any difficulty and what is more, they were not able to identify accurately which phoneme had been disturbed.
Template:Wiki
 

Haptic perception is the process of recognizing objects through Template:Wiki. It involves a combination of Template:Wiki perception of patterns on the Template:Wiki surface (e.g., edges, curvature, and Template:Wiki) and Template:Wiki of hand position and conformation. People can rapidly and accurately identify three-dimensional objects by Template:Wiki. This involves exploratory procedures, such as moving the fingers over the outer surface of the object or holding the entire object in the hand. ] Haptic perception relies on the forces experienced during Template:Wiki.

Gibson defined the haptic system as "The Template:Wiki of the Template:Wiki to the world adjacent to his body by use of his body". Gibson and others emphasized the close link between haptic perception and body Template:Wiki: haptic perception is active exploration. The Template:Wiki of haptic perception is related to the Template:Wiki of extended Template:Wiki Template:Wiki according to which, when using a tool such as a stick, Template:Wiki experience is transparently transferred to the end of the tool.
Template:Wiki
 

Template:Wiki (or, the more formal term, Template:Wiki) is the ability to Template:Wiki the Template:Wiki of Template:Wiki including, but not limited to, food. Humans receive Template:Wiki through Template:Wiki called Template:Wiki buds, or Template:Wiki calyculi, concentrated on the upper surface of the Template:Wiki. The human Template:Wiki has 100 to 150 Template:Wiki receptor Template:Wiki on each of its roughly ten thousand Template:Wiki buds. There are five primary Template:Wiki: sweetness, bitterness, sourness, saltiness, and Template:Wiki. Other Template:Wiki can be mimicked by combining these basic Template:Wiki. The recognition and awareness of Template:Wiki is a relatively recent development in Template:Wiki cuisine. The basic Template:Wiki contribute only partially to the sensation and Template:Wiki of food in the Template:Wiki — other factors include Template:Wiki, detected by the Template:Wiki epithelium of the Template:Wiki; Template:Wiki, detected through a variety of Template:Wiki, muscle Template:Wiki, etc.; and temperature, detected by thermoreceptors. All basic Template:Wiki are classified as either appetitive or aversive, depending upon whether the things they sense are harmful or beneficial.
Other senses
Main article: Sense

Other senses enable perception of body balance, acceleration, Template:Wiki, position of body parts, temperature, pain, time, and perception of internal senses such as suffocation, gag reflex, intestinal distension, fullness of Template:Wiki and urinary bladder, and sensations felt in the Template:Wiki and Template:Wiki.