Attention: The ability to focus selectively on a selected stimulus, sustaining that focus and shifting it at will. The ability to concentrate.
"Everyone knows what attention is," wrote William James in his Principles of Psychology (1890). "It is the taking possession by the mind in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought...It implies withdrawal from some things in order to deal effectively with others, and is a condition which has a real opposite in the confused, dazed, scatterbrained state."
Attention is important to learning. Learning is most efficient when a person is paying attention. Poor attention can be a key sign of behavior disorders in children such as hyperactivity, attention deficit disorder, and learning disorders.