Culture and the Individual Perception Everyday Assumptions about Perception • Phenomenal absolutism - the assumption that the world is as you see it. • Perceptual constancy - the perception that objects keep their size no matter how far away they are Approaches to Studying Perception • Nativists - perception is based on the structural limits of the human nervous system (is genetically/biologically based) e.g. Gibson - three dimensional world is viewed through the two dimensional surface of the retina • Empiricists - perception is highly influenced by the kinds of experience people have (is learned) Brunswik's Empiricist Theory A Base for Cross-Cultural Research Egon Brunswik (1950s) • perception involves transactions between an organism and incoming sensory materials, • perception is the combined product of the object and the perceiver, with experience being very important Tuning Fork Figure Draw this figure. Impossible Figures This figure is usually perceived by western educated people as a three dimensional figure that is difficult to draw accurately from memory. It is usually perceived by people from traditional societies as a two dimensional figure that is easy to draw accuratelyfrom memory. Symbolizing Three Dimensions in Two • Symbols on paper in literate societies, maps, writing • Experience with representational drawings should increase susceptibility to three-dimensions-in two illusions • Photographs Photographs Black and White Vs Color • African natives who do not have experience with two dimensional representations of objects CANNOT identify objects in black and white photos. • They CAN identify objects in color photos. Sander Parallelogram Muller-Lyer Muller-Lyer Muller-Lyer Muller-Lyer Carpentered World Hypothesis Muller-Lyer and the Carpentered World Hypothesis Muller-Lyer • The illusion is not cross-cultural. Non-Western subjects, and particularly subjects whose day-today surroundings are usually not rectangular (few buildings, doors, walls) are much less likely to be affected by it (Segall, et al., 1963). Researchers discovered that the Zulu people, whose typical dwellings are circular thatched huts with no angular walls, were much less susceptible to the illusion. The Carpentered World Hypothesis Parallelogram illusion Muller-Lyer illusion • Carpentered environment causes interpretation of non-rectangular objects as rectangular • Carpentered environment causes perception to take on depth perspective • Carpentered environments cause perception of three dimensions as two Frontal-horizontal Foreshortening Horizontal-vertical illusion • Open, spacious environments lead to horizontal-vertical illusions • Urban, canyon or forest dwellers will be less susceptible to horizontal-vertical illusion Frontal-horizontal Foreshortening Ebbinghaus Which red circle is larger? Smaller? Ebbinghaus Illusion • The Ebbinghaus (Titchener) illusion was examined in a remote culture (Himba) with no words for geometric shapes. The illusion was experienced less strongly by Himba compared with English participants, leading to more accurate size contrast judgments in the Himba. The study included two conditions of inducing stimuli. The illusion was weaker when the inducing stimuli were dissimilar (diamonds) to the target (circle) compared with when they were similar (circles). However, the illusion was weakened to the same extent in both cultures. It is argued that the more accurate size judgments of the Himba derive from their tendency to prioritize the analysis of local details in visual processing of multiple objects, and not from their impoverished naming. (PsycINFO Database Record (c) 2007 APA, all rights reserved)(from the journal abstract) Figure and Ground Figure and Ground Figure and Ground Americans begin by describing the figures that are in the foreground: Three women sitting on a boat Three men walking together Asians (Japanese, Korean, Chinese) begin be describing the background/context The beach with sand and water in an area in which fishing is a major activity Color Perception • Now, a new study by researchers at the University of Surrey suggests that the process of learning new color categories produces subtle but significant changes in how people actually perceive those colors. • The findings, published in the Journal of Experimental Psychology: General (Vol. 131, No. 4), support the linguistic relativity hypothesis-the idea that the language one speaks can affect the way one thinks about and perceives the world. • "The main conclusions of the study are basic: that color perception is not as rigid and inflexible as was thought before," says the study's lead author, Emre Ozgen, PhD. "This is the first time that it's been shown that a new perceptual color category boundary can actually be induced through laboratory training." Illusion Suceptibility • Westerners are more easily fooled by the Muller-Lyer illusion than folks from traditional societies • Folks from traditional society are more easily fooled by the Horizontal-Vertical foreshortening effect Conclusions • Illusions may occur due to learned habits inappropriately applied • Different inference habits are learned in different physical and cultural environments • As people age, they become less susceptible to illusions