Target cuing in visual search: The effects of conformality and display location on the allocation of visual attention

Two experiments were performed to examine how frame of reference (world-ref erenced vs. screen-referenced) and target expectancy can modulate the effec ts of target cuing in directing attention for see-through helmet-mounted di splays (HMDs). In the first experiment, the degree of world referencing was varied by the spatial accuracy of the cue; in the second, the degree of wo rld referencing was varied more radically between a world-referenced HMD an d a hand-held display. Participants were asked to detect, identify, and giv e azimuth information for targets hidden in terrain presented in the far do main (i.e., the world) while performing a monitoring task in the near domai n (i.e., the display). The results of both experiments revealed a cost-bene fit trade-off for cuing such that the presence of cuing aided the target de tection task for expected tal gets but drew attention away from the presenc e of unexpected targets in the environment. Analyses support the observatio n that this effect call be mediated by the display: The world-referenced di splay reduced the cost of cognitive tunneling relative to the screen-refere nced display in Experiment 1; this cost was further reduced in Experiment 2 when participants were using a hand-held display. Potential applications o f this I research include important design guidelines and specifications fo r automated tar target recognition systems as well as any terrain-and-targe ting display system in which superimposed symbology is included, specifical ly in assessing the costs and benefits of attentional cuing and the means b y which this information is displayed.