Head-Up vs. Head-Down: Effects of Precision on Cue Effectiveness and Display Signaling

Two experiments were conducted to investigate the attentional effects in the presentation of cueing symbology with the use of a helmet-mounted display (HMD) relative to a handheld display, and how reduced cue precision (experiment 1) and increased clutter (experiment 2) might modulate these effects. Participants were asked to detect, identify, and give azimuth information for targets hidden in terrain presented in the far domain (i.e., the world) while performing a monitoring task in the near domain (i.e., the display) using either a HMD or hand-held display. The results revealed overall cueing benefits in target detection performance, with slight decrements when cue imprecision was greater than 7.5°. More importantly, undertrust of the cueing data, induced by decreased precision, widened attentional breadth on trials after the automation unexpectedly failed.