Dynamic Allocation of Attention in Aging and Alzheimer Disease

Abstract
THE LIMITED information processing capacity of the brain creates a situation where only parts of the environment can become the focus of attention at any given time. In the visual modality, global attention encompasses the entire extrapersonal space and is used for the rapid detection of novel events. Such events can then attract a more focused sort of attention for detailed assessment. These shifts of visual attention can occur overtly, through shifts in gaze, or covertly, without eye movements.