Abstract
A whirlwind review of the methods used to quantitatively define the temporal, spatial, and featural properties of attention, and some of their interactions. The temporal window of attention is measured by moving attention from one location to another in which a rapid sequence of different items (e.g., letters or numbers) is being presented. The probability of items from that sequence entering short-term memory defines the time course of attention: typically 100 msec to window opening, maxim at 300-400 msec, and 800 msec to closing. Spatial attention is defined like acuity, by the ability to alternately attend and ignore strips of increasingly finer grids. The spatial frequency characteristic so measured then predicts achievable attention distributions to arbitrarily defined regions. Featural attention is defined by the increased salience of items that contain to-be-attended features. This can be measured in various ways; quickest is an ambiguous motion task which shows that attended features have 30% greater salience than neutral features. Spatio-temporal interaction is measured when attention moves as quickly as possible to a designated area. Attention moves in parallel to all the to-be-attended areas, i.e., temporal-spatial independence. Independence of attentional modes is widely observed; it allows the most efficient neural processing.