User:Tyler Colgrove/Perception

Feature Integration Theory
Main Article: Feature Integration Theory

Anne Treisman's Feature Integration Theory attempts to explain how characteristics of a stimulus such as physical location in space, motion, color, and shape are merged to form one percept despite each of these characteristics activating separate areas of the cortex. The Feature Integration Theory of perception explains this through a two part system of perception involving the preattentive and focused attention stages.

The preattentive stage of perception is largely unconscious, and analyzes an object by breaking it down into its basic features. These features include things such as the specific color, geometric shape, motion, depth, individual lines, and many others. This stage was studied by Ana Treisman and Hilary Schmidt by briefly flashing groups of differently colored shapes flanked by black numbers. After the groups of shapes were presented, the participants were asked to recount the numbers, then the shape and colors of each item between them. In 18 percent of the tests, the participants reported seeing shapes made up of the combined features of two different stimuli, thereby referred to as illusory conjunctions.

The unconnected features described in the preattentive stage are combined into the objects one normally sees during the focused attention stage. The focused attention stage is based heavily around the idea of attention in perception. The importance of this was illustrated in another modified instance of the test used to investigate the preattentive stage. In this second test the participants were instructed to ignore the black numbers and focus their attention on the shapes and their colors. When the participants did this, they were able to eliminate the illusory conjunctions that had caused the errors in the previous test.