When is Less More? Attention and Workload in Auditory, Visual, and Redundant Patient-Monitoring Conditions

Abstract

Auditory signals can take the form of “auditory displays” that communicate information redundant to visual displays. These redundant displays may allow offloading some visual workload to the auditory channel. The current study examines the effect of visual, auditory and redundant displays on the performance of a dual-task simulation of patient monitoring. Subjects performed manual compensatory tracking task while monitoring six vital signs of a simulated patient, detecting deviations from normal levels. Monitoring was presented in three display conditions: auditory only, visual only, and redundant. Results indicate that the detection of deviations in visual and redundant conditions were not significantly different, but faster than the auditory display. However, performance in the tracking task was degraded least in the auditory condition, and the redundant display resulted in poorest performance—an example of a negative redundancy-gain. Reasons for this finding are examined through data from eye-movement recordings. This negative redundancy gain is also discussed.