Figure–ground (perception)

{{Short description|Humans' ability to separate foreground from background in visual images}} {{Lead too short|date=December 2019}} [[File:Cup or faces paradox.svg|thumb|The Rubin vase illusion, where it is ambiguous which part is the figure and which the ground]] thumb|Shapes which can be read as a word once the viewer recognises them as being the isolated negative spaces of a word

'''Figure–ground''' organization is a type of perceptual grouping that is a vital necessity for recognizing objects through vision. In Gestalt psychology it is known as identifying a ''figure'' from the back''ground''. For example, black words on a printed paper are seen as the "figure", and the white sheet as the "background".<ref>Schacter, Daniel L., Daniel T. Gilbert, and Daniel M. Wegner. "Chapter 4: Sensation and Perception, Vision II: Recognizing What We Perceive." Psychology. ; Second Edition. N.p.: Worth, Incorporated, 2011. 149-50. Print.</ref>

== Gestalt psychology ==

The Gestalt theory was founded in the 20th century in Austria and Germany as a reaction against the associationist and structural schools' atomistic orientation.<ref>{{Cite web|url=https://www.britannica.com/science/Gestalt-psychology|title=Gestalt psychology {{!}} Definition, Founder, Principles, & Examples|website=Encyclopædia Britannica|language=en|access-date=2019-12-10}}</ref> In 1912, the Gestalt school was formed by Max Wertheimer, Wolfgang Köhler, and Kurt Koffka. The word "gestalt" is a German word translated to English as "pattern" or "configuration."<ref>{{Citation|title=gestalt|url=https://medical-dictionary.thefreedictionary.com/gestalt|work=The Free Dictionary|access-date=2019-12-10}}</ref> Gestalt concepts can also be referred to as "holism."<ref>{{Cite journal|last1=Wagemans|first1=Johan|last2=Feldman|first2=Jacob|last3=Gepshtein|first3=Sergei|last4=Kimchi|first4=Ruth|last5=Pomerantz|first5=James R.|last6=van der Helm|first6=Peter A.|last7=van Leeuwen|first7=Cees|date=2012|title=A century of Gestalt psychology in visual perception: II. Conceptual and theoretical foundations.|journal=Psychological Bulletin|language=en|volume=138|issue=6|pages=1218–1252|doi=10.1037/a0029334|issn=1939-1455|pmc=3728284|pmid=22845750}}</ref> Gestalt Psychologists were attempting to humanize what was considered a sterile approach. Gestalt psychology establishes that the whole of anything is greater than its parts. The concepts explored by Wertheimer, Köhler, and Koffka in the 20th century established the foundation for the modern study of perception.<ref>{{Citation|chapter=Information TheoryReprinted with permission from Encyclopædia Britannica, 14th edition, 1968 by Encyclopædia Britannica, Inc.|date=2009|publisher=IEEE|isbn=978-0-470-54424-2|doi=10.1109/9780470544242.ch14|title=Claude E. Shannon}}</ref>

"The ''Gestalt'' concept is that ''"not only movement, or process as such, but also the direction and distribution of process is determined dynamically by interaction."'' Sensory organization is not dependent upon isolated stimuli and local stimulation, but upon the relative properties of stimulation and the dynamical context."<ref>{{Cite web|url=https://psycnet.apa.org/record/1929-02130-000|title=PsycNET|website=psycnet.apa.org|language=en|access-date=2019-12-10}}</ref>

Wertheimer described holism as the "fundamental formula" of Gestalt psychology: "There are wholes, the behavior of which is not determined by that of their individual elements, but where the part-processes are themselves determined by the intrinsic nature of the whole."<ref>{{Cite journal|last1=Wagemans|first1=Johan|last2=Feldman|first2=Jacob|last3=Gepshtein|first3=Sergei|last4=Kimchi|first4=Ruth|last5=Pomerantz|first5=James R.|last6=van der Helm|first6=Peter A.|last7=van Leeuwen|first7=Cees|date=November 2012|title=A century of Gestalt psychology in visual perception: II Conceptual and theoretical foundations|journal=Psychological Bulletin|volume=138|issue=6|pages=1218–1252|doi=10.1037/a0029334|pmid=22845750|pmc=3728284|issn=0033-2909}}</ref>

==Examples== [[File:Man and crane, Mangas-Mimbres pot.jpg|thumb|Man and crane, Mimbres culture pot, c. 1000 -1150 AD]] The Rubin vase faces–vase drawing that Danish psychologist Edgar Rubin described <ref>Rubin, E. (1921) ''Visuell Wahrgenommene Figuren : Studien in psychologischer Analyse''. Kobenhaven: Gyldendalske boghandel.</ref><ref>Rubin, E. (2001). Figure and Ground. In Yantis, S.(Ed.), ''Visual Perception''. (pp. 225-229). Philadelphia, Psychology Press</ref> exemplifies one of the key aspects of figure–ground organization, edge-assignment and its effect on shape perception. In the faces–vase drawing, the perceived shape depends critically on the direction in which the border (edge) between the black and white regions is assigned. If the edges between the black and white regions are assigned inward, then the central white region is seen as a vase shape in front of a black background. No faces are perceived in this case. On the other hand, if the edges are assigned outward, then the two black profile faces are perceived on a white background, and no vase shape is perceived. The human visual system will settle on either of the interpretations of the Rubin vase and alternate between them, a phenomenon known as multistable perception. Functional brain imaging shows that, when people see the Rubin image as a face, there is activity in the temporal lobe, specifically in the face-selective region.<ref>Schacter, L.D., Gilbert, D.T., Wegner, D.M. (2011). "Psychology (2nd ed.)." New York, NY: Worth Publishers</ref><ref>Hasson, U., Hendler, T., Ben Bashat, D., and Malach, R. (2001). Vase or face? A neural correlate of shape-selective grouping processes in the human brain. J. Cogn. Neurosci. 13, 744–753.</ref>

An additional example is the "My Wife and My Mother-in-Law" illusion drawing. The image is famous for being reversible. "The viewer may either observe a young girl with her head turned to the right or an old woman with a large nose and protruding chin, depending on one's perspective."<ref>{{Cite web|url=https://www.researchgate.net/figure/The-young-girl-old-woman-illusion-otherwise-known-as-My-Wife-and-My-Mother-in-Law-is_fig4_271842692|title=Figure 5: The young girl-old woman illusion (otherwise known as "My...|website=ResearchGate|language=en|access-date=2019-12-10}}</ref>

The Flag of Canada has also been cited as an example of figure–ground reversal, in which the background edges of the maple leaf can also be seen as two faces arguing.<ref>Rudolf Arnheim, ''Art and Visual Perception: A Psychology of the Creative Eye''. New Version. University of California Press, 1974, p. 228.</ref>

== Development == Figure–ground perception precedes all other visual perceptual skills and is one of the first to develop in a young baby.<ref>{{Cite web|url=https://www.educanda.co.za/news/early_learning_figure_ground_development_in_babys_and_toddlers|title=Early learning: Figure Ground Development in baby's and toddlers|last=cc|first=21 Digital Web Solutions|website=Educanda|language=en|access-date=2019-12-11|archive-date=2019-12-11|archive-url=https://web.archive.org/web/20191211181044/https://www.educanda.co.za/news/early_learning_figure_ground_development_in_babys_and_toddlers|url-status=dead}}</ref> The development of perceptual organization develops as early as infancy in human beings. In regards to nature versus nurture, concepts such as "lightness" and "proximity" may develop as early as birth, but recognizing "form similarity" may not be functional until activated by particular experiences.<ref>{{Cite journal|last1=Quinn|first1=Paul C.|last2=Bhatt|first2=Ramesh S.|date=2018-08-28|title=Size and orientation cue figure-ground segregation in infants|journal=Visual Cognition|volume=26|issue=7|pages=518–529|language=en|doi=10.1080/13506285.2018.1505794|pmc=6786798|pmid=31602175}}</ref>

Three- to four-month olds respond to differences in lightness rather than differences in form similarity. It is suggested that scaffolding (the development of new skills over time based on the building of other skills) is responsible for the development of perceptual organization. Environment plays a major role in the development of figure-ground perception.<ref>{{Cite journal|last1=Quinn|first1=Paul C.|last2=Bhatt|first2=Ramesh S.|date=2018-08-28|title=Size and orientation cue figure-ground segregation in infants|journal=Visual Cognition|volume=26|issue=7|pages=518–529|language=en|doi=10.1080/13506285.2018.1505794|pmc=6786798|pmid=31602175}}</ref>

The development of figure–ground perception begins the day the baby can focus on an object. The faces of caregivers, parents, and familiar objects are the first to be focused on and understood. As babies develop, they learn to distinguish the objects they desire from their surroundings. Sitting up, crawling, and walking present ample opportunity to develop the skill during development. Between the ages of 2–4 the skill can be further cultivated by teaching the child to group or sort items.<ref>{{Cite web|url=https://www.educanda.co.za/news/early_learning_figure_ground_development_in_babys_and_toddlers|title=Early learning: Figure Ground Development in baby's and toddlers|last=cc|first=21 Digital Web Solutions|website=Educanda|language=en|access-date=2019-12-11|archive-date=2019-12-11|archive-url=https://web.archive.org/web/20191211181044/https://www.educanda.co.za/news/early_learning_figure_ground_development_in_babys_and_toddlers|url-status=dead}}</ref>

==Perceptual process== The perceptual decision in which the brain decides which item is the figure and which are part of the ground in a visual scene can be based on many cues, all of which are of a probabilistic nature. For instance, size assists in distinguishing between the figure and the ground, as smaller regions are often (but not always) figures. Object shape can assist in distinguishing figure from ground because figures tend to be convex. Movement also helps; the figure may be moving against a static environment. Color is also a cue because the background tends to continue as one color behind potentially multiple foreground figures, whose colors may vary. Edge assignment also helps; if the edge belongs to the figure, it defines the shape while the background exists behind the shape. However, it is sometimes difficult to distinguish between the two because the edge that would separate figure from ground is part of neither, equally defining both the figure and the background.<ref>{{cite book | last1 = Schacter | first1 = Daniel L. | first2 = Gilbert | last2 = Daniel T. | first3 = Wegner | last3 = Daniel M. | title = Psychology: Second Edition | location = United States of America | publisher = Worth Publishers | date = March 2011 | pages = [https://archive.org/details/psychology0000scha/page/149 149] | isbn = 978-1-4292-3719-2 | title-link = Psychology: Second Edition }}</ref>

The LOC (lateral occipital cortex) is highly important for figure–ground perception. This region of the visual cortex (located lateral to the fusiform gyrus and extending anteriorly and ventrally) has consistently shown stronger activation in response to objects versus non-objects."<ref>{{Cite journal|last1=Pitts|first1=Michael A.|last2=Martínez|first2=Antígona|last3=Brewer|first3=James B.|last4=Hillyard|first4=Steven A.|date=April 2011|title=Early stages of figure-ground segregation during perception of the face-vase|journal=Journal of Cognitive Neuroscience|volume=23|issue=4|pages=880–895|doi=10.1162/jocn.2010.21438|pmid=20146604|pmc=3071650|issn=0898-929X}}</ref><ref>{{Cite journal|last1=Molloy|first1=Katharine|last2=Lavie|first2=Nilli|last3=Chait|first3=Maria|date=2019-02-27|title=Auditory figure-ground segregation is impaired by high visual load|journal=The Journal of Neuroscience|volume=39|issue=9|pages=1699–1708|doi=10.1523/JNEUROSCI.2518-18.2018|pmid=30541915|pmc=6391559|issn=0270-6474}}</ref>

Evidently, the process of distinguishing figure from ground (sometimes called figure–ground segmentation) is inherently probabilistic, and the best that the brain can do is to take all relevant cues into account to generate a probabilistic best-guess. In this light, Bayesian figure–ground segmentation models have been proposed to simulate the probabilistic inference by which the brain may distinguish figure from ground.<ref>{{cite journal|last=Goldreich|first=D|author2=Peterson, MA|title=A Bayesian observer replicates convexity context effects in figure–ground perception.|journal=Seeing and Perceiving|year=2012|volume=25|issue=3–4|pages=365–95|pmid=22564398|doi=10.1163/187847612X634445}}</ref><ref>{{cite journal|last=Barghout|first=L|author2=Lee, L|title=Perceptual information processing system.|journal=USPatent Patent Application 10/618,543|year=2003}}</ref>

Subjective factors can also influence figure–ground perception. For instance, if a viewer has the intention to perceive one of the two regions as the figure, it will likely alter their ability to analyze the two regions objectively. In addition, if a viewer's gaze is fixated on a particular region, the viewer is more likely to view the fixated region as the figure. Although subjective factors can alter the probability of seeing the figure on one particular side of an edge, they tend not to overpower compositional cues.<ref>{{Cite journal|last1=Peterson|first1=Mary|last2=Salvagio|first2=Elizabeth|date=2010|title=Figure-ground perception|journal=Scholarpedia|volume=5|issue=4|pages=4320|doi=10.4249/scholarpedia.4320|bibcode=2010SchpJ...5.4320P|issn=1941-6016|doi-access=free}}</ref>

== Artistic applications == [[File:Ambigram tessellation Liar Jail - figure-ground.png|thumb|Figure-ground ambigram tessellation displaying the words Liar / Jail alternatively, using negative space.]] Figure–ground organization is used to help artists and designers in composition of a 2D piece. Figure–ground reversal may be used as an intentional visual design technique in which an existing image's foreground and background colors are purposely swapped to create new images.

==Non-visual== Figure–ground perception can be expanded from visual perception to include non-visual concepts such as melody/harmony, subject/background and positive/negative space.{{Citation needed|reason=Reliable source needed for the whole sentence|date=October 2016}} The concept of figure and ground fully depends on the observer and not on the item itself.<ref name="figure and ground">{{cite book |last=Carlson |first=Neil R |title=Psychology the science of behaviour-figure and ground |year=2010 |publisher=Pearson Canada |location=US |isbn=978-0-205-64524-4 |pages=[https://archive.org/details/psychologyscienc0004unse/page/175 175] |url=https://archive.org/details/psychologyscienc0004unse/page/175 }}</ref>

In the typical sonic scenarios people encounter, auditory figure and ground signals often overlap in time as well as in frequency content. In these situations, auditory objects are established by integrating sound components both over time and frequency.<ref>{{Cite journal|last1=Tóth|first1=Brigitta|last2=Kocsis|first2=Zsuzsanna|last3=Háden|first3=Gábor P.|last4=Szerafin|first4=Ágnes|last5=Shinn-Cunningham|first5=Barbara G.|last6=Winkler|first6=István|date=May 2018|title=Corrigendum to "EEG signatures accompanying auditory figure-ground segregation" [NeuroImage (2017) volume 141, pp. 108–119]|journal=NeuroImage|volume=172|pages=915|doi=10.1016/j.neuroimage.2017.12.001|pmid=29233621|pmc=8963124 |issn=1053-8119|doi-access=free}}</ref> A 2011 study suggests that the auditory system possesses mechanisms that are sensitive to such cross-frequency and cross-time correlations. Results of this study demonstrated significant activations in the intraparietal sulcus (IPS) and the superior temporal sulcus related to bottom-up, stimulus-driven figure–ground decomposition.<ref>{{Cite journal|last1=Teki|first1=S.|last2=Chait|first2=M.|last3=Kumar|first3=S.|last4=von Kriegstein|first4=K.|last5=Griffiths|first5=T. D.|date=2011-01-05|title=Brain Bases for Auditory Stimulus-Driven Figure-Ground Segregation|journal=Journal of Neuroscience|volume=31|issue=1|pages=164–171|doi=10.1523/jneurosci.3788-10.2011|pmid=21209201|pmc=3059575|issn=0270-6474|doi-access=free}}</ref>

In crowded rooms or parties, a person is able to zero in on the conversation they are having with one person (figure) while drowning out the background noise (ground). This can also be referred to as the "cocktail party effect."<ref>{{Cite web|url=https://cas.tulane.edu/login?service=https%3A%2F%2Ftulane.instructure.com%2Flogin%2Fcas|title=Tulane University Central Authentication Service 1p01|website=cas.tulane.edu|access-date=2019-12-10|archive-date=2019-12-17|archive-url=https://web.archive.org/web/20191217134406/https://cas.tulane.edu/login?service=https%3A%2F%2Ftulane.instructure.com%2Flogin%2Fcas|url-status=dead}}</ref>

Figure–ground segregation in hearing is not automatic; rather, it requires attention<ref>{{Cite journal|last1=Molloy|first1=Katharine|last2=Lavie|first2=Nilli|last3=Chait|first3=Maria|date=2019-02-27|title=Auditory figure-ground segregation is impaired by high visual load|journal=The Journal of Neuroscience|volume=39|issue=9|pages=1699–1708|doi=10.1523/JNEUROSCI.2518-18.2018|pmid=30541915|pmc=6391559|issn=0270-6474}}</ref> and draws on resources that are shared across vision and audition.<ref>{{Cite journal|last1=Houtkamp|first1=R.|last2=Roelfsema|first2=P. R.|date=2004-08-01|title=Figure-ground and figure-figure segregation in curve tracing|journal=Journal of Vision|volume=4|issue=8|pages=199|doi=10.1167/4.8.199|issn=1534-7362|doi-access=free}}</ref>

==Types of figure–ground problems== thumb|Type 2: The ground itself is the figure. There are three types of figure–ground problems: #The figure and the ground compete. #The figure should be the ground and the ground should be the figure. #The figure and ground create an optical illusion.<ref>Lohr L. Creating Graphics for Learning and Performance: Lessons in Visual Literacy Cleveland, OH: Prentice-Hall, 2007.</ref>

==References== {{reflist}}

==External links== *[https://www.clockworkgoldfish.com/figureground/ Figure Ground], a puzzle game plays on the figure–ground illusion.

{{DEFAULTSORT:Figure-Ground (Perception)}} Category:Design Category:Optical illusions Category:Dichotomies Category:Perception Category:Cognitive psychology