Table 3.

Towards a taxonomy of spatially oriented attention.

Conditions			Effects
Cue Type	Set Size or Workload	Judgment Precision	Asymptotic Accuracy	Stimulus Enhancement	External Noise Exclusion
Endogenous	Low	Low	No	No	Yes
		High	Yes	No	Yes
	High	Low	No	No	Yes
		High	Yes	No	Yes
Exogenous	Low	Low	No	Sometimes	Yes
		High	Yes	Sometimes	Yes
	High	Low	No	Sometimes	Yes
		High	Yes	Sometimes	Yes

Note: External noise exclusion occurs in high external noise or masked conditions. Stimulus enhancement occurs in low or zero external noise conditions. Stimulus enhancement may occur in some circumstances for peripheral precuing.