 In 1963, the psychologist Eleanor Gibson wrote a landmark survey article on perceptual learning in which she purported to define the term. According to Gibson, perceptual learning is “[a]ny relatively permanent and consistent change in the perception of a stimulus array, following practice or experience with this array…” (1963:  29).[1]  Gibson’s definition has three basic parts. First, perceptual learning is long-lasting. Second, it is perceptual. Third, it is the result of practice or experience. This entry expands on each of these features of the definition.