PART 6: Sensation and Perception

16.6 Context Effects

Page 207

A given stimulus may trigger radically different perceptions, partly because of our differing perceptual set (FIGURE 16.9), but also because of the immediate context. Some examples:

Figure 6.9: FIGURE 16.9 Culture and context effects What is above the woman’s head? In one classic study, nearly all the rural East Africans questioned said the woman was balancing a metal box or can on her head and that the family was sitting under a tree. Westerners, for whom corners and boxlike architecture were more common, were more likely to perceive the family as being indoors, with the woman sitting under a window (Gregory & Gombrich, 1973).

When holding a gun, people become more likely to perceive another person as gun-toting—a phenomenon that has led to the shooting of some unarmed people who were actually holding their phone or wallet (Witt & Brockmole, 2012).
Imagine hearing a noise interrupted by the words “eel is on the wagon.” Likely, you would actually perceive the first word as wheel. Given “eel is on the orange,” you would more likely hear peel. This curious phenomenon suggests that the brain can work backward in time to allow a later stimulus to determine how we perceive an earlier one. The context creates an expectation that, top-down, influences our perception (Grossberg, 1995).
How is the woman in FIGURE 16.10 feeling?

Figure 6.10: FIGURE 16.10 What emotion is this? (See FIGURE 16.11 below.)

Craig Klomparens

Figure 6.11: FIGURE 16.11 Context makes clearer The Hope College volleyball team celebrates its national championship winning moment.

Craig Klomparen

RETRIEVE IT

Question

Does perceptual set involve bottom-up or top-down processing? Why?

ANSWER: It involves top-down processing. Our perceptual set influences our interpretation of stimuli based on our experiences, assumptions, and expectations.