Feature integration theory: Difference between revisions

Revision as of 22:19, 27 April 2018

Revision as of 22:23, 27 April 2018

Line 6:

The second stage of the feature integration theory is the focused attention stage, where the individual features of an object combine in order to perceive the whole object. In order to combine the individual features of an object, attention is required and selection of that object occurs within a "master map" of locations. The master map of locations contains all of the locations in which features have been detected, with each ___location in the master map having access to the multiple feature maps. When attention is focused at a particular ___location on the map, the features currently in that position are attended to and are stored in "object files". If the object is familiar, associations are made between the object and prior knowledge, which results in identification of that object. In support of this stage, researchers often refer to patients suffering from [[Balint's syndrome]]. Due to damage in the parietal lobe, these people are unable to focus attention on individual objects. Given a stimulus that requires combining features, people suffering from Balint's syndrome are unable to focus attention long enough to combine the features, providing support for this stage of the theory.

[[File:FITstages.png|alt=The stages of feature integration theory|thumb|300px|The stages of feature integration theory]]

Treisman distinguishes between two kinds of visual search tasks, "feature search" and "conjunction search". Feature searches can be performed fast and pre-attentively for targets defined by only one feature, such as color, shape, perceived direction of lighting, movement, or orientation. Features should "pop out" during search and should be able to form illusory conjunctions. Conversely, conjunction searches occur with the combination of two or more features and are identified serially. Conjunction search is much slower than feature search and requires conscious attention and effort. In multiple experiments, some referenced in this article, Treisman concluded that [[color]], [[Orientation (geometry)|orientation]], and [[intensity (disambiguation)|intensity]] are features for which feature searches may be performed.

Line 17:

As previously mentioned, Balint's syndrome patients have provided support for the feature integration theory. Particularly, Research participant R.M., a [[Bálint's syndrome]] sufferer who was unable to focus attention on individual objects, experiences illusory conjunctions when presented with simple stimuli such as a "blue O" or a "red T." In 23% of trials, even when able to view the stimulus for as long as 10 seconds, R.M. reported seeing a "red O" or a "blue T".<ref>Friedman-Hill et al., 1995; Robertson et al., 1997.</ref> This finding is in accordance with feature integration theory's prediction of how one with a lack of focused attention would erroneously combine features.

[[File:treismanshapes.png|thumb|alt=The stimuli resembling a carrot, lake and tire, respectively.|The stimuli resembling a carrot, lake and tire, respectively. Treisman et al.(1986).]]

If people use their prior knowledge or experience to perceive an object, they are less likely to make mistakes, or illusory conjunctions. In order to explain this phenomenon, Treisman and Souther (1986) conducted an experiment in which they presented three shapes to participants where illusory conjunctions could exist. Surprisingly, when she told participants that they were being shown a carrot, lake, and tire (in place of the orange triangle, blue oval, and black circle, respectively), illusory conjunctions did not exist.<ref>Illusory words: The roles of attention and of top–down constraints in conjoining letters to form words.

By Treisman, Anne; Souther, Janet. Journal of Experimental Psychology: Human Perception and Performance, Vol 12(1), Feb 1986, 3-17.</ref> Treisman maintained that prior-knowledge played an important role in proper perception. Normally, bottom-up processing is used for identifying novel objects; but, once we recall prior knowledge, top-down processing is used. This explains why people are good at identifying familiar objects rather than unfamiliar.

Line 28 ⟶ 30:

* [[Visual search]]

===Notes===

<references/>

==References==

* Anne Treisman and [[Garry Gelade]] (1980). "A feature-integration theory of attention." ''Cognitive Psychology'', Vol. 12, No. 1, pp.&nbsp;97–136.

* Anne Treisman and [[Hilary Schmidt]] (1982). "Illusory conjunctions in the perception of objects." ''Cognitive Psychology'', Vol. 14, pp.&nbsp;107–141.<ref>'''Abstract'''

* Anne Treisman and [[Janet Souther]] (1986). "Illusory words: The roles of attention and of top–down constraints in conjoining letters to form words." ''Journal of Experimental Psychology: Human Perception and Performance'', Vol 12(1), pp.&nbsp;3–17

<br>In perceiving objects we may synthesize conjunctions of separable features by directing attention serially to each item in turn (A. Treisman and G. Gelade, ''Cognitive Psychology'', 1980, 12, 97-136). This feature-integration theory predicts that when attention is diverted or overloaded, features may be wrongly recombined, giving rise to "illusory conjunctions." The present paper confirms that illusory conjunctions are frequently experienced among unattended stimuli varying in color and shape, and that they occur also with size and solidity (outlined versus filled-in shapes). They are shown both in verbal recall and in simultaneous and successive matching tasks, making it unlikely that they depend on verbal labeling or on memory failure. They occur as often between stimuli differing on many features as between more similar stimuli, and spatial separation has little effect on their frequency. Each feature seems to be coded as an independent entity and to migrate, when attention is diverted, with few constraints from the other features of its source or destination.</ref>

*Anne Treisman and [[Janet Souther]] (1986). "Illusory words: The roles of attention and of top–down constraints in conjoining letters to form words." ''Journal of Experimental Psychology: Human Perception and Performance'', Vol 12(1), pp.&nbsp;3–17

* Anne Treisman (1988). "Features and objects: the fourteenth Bartlett Memorial Lecture." ''Quarterly Journal of Experimental Psychology'', 40A, pp.&nbsp;201–236.

*Anne Treisman and [[Nancy Kanwisher]] (1998). "Perceiving visually presented objects: recognition, awareness, and modularity." ''Current Opinion in Neurobiology'', '''8''', pp.&nbsp;218–226.

* J. M. Wolfe (1994). "Guided Search 2.0: A revised model of visual search." ''Psychonomic Bulletin & Review'', Vol 1, pp.&nbsp;202–238

== External links ==