Graded representations in behavioral dissociations.

Why do people sometimes seem to know things when they are tested in one way, while seeming unaware of this information when tested in a different way? Such task-dependent behaviors, or dissociations, often occur in infants and children, and in adults following brain damage. To explain these dissociations, researchers have posited separable knowledge systems that are differentially tapped by various tasks, develop at different rates and can be selectively impaired. There is an alternative account in which knowledge is viewed as graded in nature. Certain tasks tap weaker representations, while other tasks require stronger representations, leading to dissociations in behavior. The graded representations approach addresses dissociations observed in perception, attention, memory, executive functioning and language, and has implications for the organization, development and impairment of our cognitive systems.