ABSTRACT
Attention is a term that is widely used in cognitive science but very rarely defined adequately. It can be used interchangeably with the term selection but both of these terms are of little use unless some effort is made to explain the purpose and the mechanism whereby selection is taking place. Broadbent (1971), who was an early proponent of the information-processing approach to understanding behavior, proposed that selective attention reflected the underlying capacity limitations of the human brain:
If there were really sufficient machinery available to the brain to perform such an analysis for every stimulus, and then use the results to decide which should be selected, it is difficult to see why any selection at all should occur. The obvious utility of a selection system is to produce an economy in mechanism.
(p. 147) For Broadbent (1971), the reason for selection was to protect the brain from information overload. He stated: “selection takes place in order to protect a mechanism of limited capacity” (p. 178). However, this argument is clearly circular in that the evidence for limited capacity is the occurrence of selection and yet selection exists in order to protect the limited capacity which in turn, is evoked to explain selection.