Detection of Changes in Naturalistic Scenes: Comparisons of Individuals With and Without Mental Retardation

Abilities of individuals with and without mental retardation to search for and detect salient changes to naturalistic scenes were investigated using the flicker paradigm. Located in areas of central or marginal interest, changes involved an object’s color, shape, or presence. Individuals with mental retardation required more time to detect changes of all types, and the magnitude of the group difference was more pronounced for marginal-interest changes. Supplemental eye-tracking data from 6 participants suggested that the basis of this effect was that individuals with mental retardation tended to maintain gaze in the region of central interest for longer periods of time prior to sampling the other areas of the scene. Implications for intelligence-related differences in visual attention are discussed. Visual search skills are critical for acquiring visual information from the environment effi-ciently and accurately. Their importance for un-derstanding performance differences between in-dividuals with and without mental retardation has been the focus of research for more than 30 years. Early visual search studies involving individuals with mental retardation provided important in-formation about the influences of stimulus struc-ture on search performance (e.g., Spitz, 1969), eye and head movement patterns (e.g., Atkin, Bala