Abstract & Overview
Although most research and theory building on human operator performance has considered the operator to be a continuous single-channel controller, straightforward examination of real situations and real behavior shows him to be a sampleddata, commutated single-channel controller. This arises from the fact that the human operator must distribute his attention sequentially over many information sources. Both monitoring and controlling behavior are subject to the constraint that the operator's eyes can fixate on only one place at a time.