Evaluation of preview cues to enhance recall of auditory sequential information

Abstract

Background: In previous work, an auditory vital sign display of five patients was developed. Sounds denoting the vital signs of each patient were delivered in order, with a special sound for any patient whose vital signs were all normal. Although the display was effective, accuracy decreased as the number of abnormal patients increased. We wondered whether accuracy would improve with a preview sound indicating the number of patients with abnormal vital signs in the upcoming sequence by reducing working memory load. We also wondered whether the preview sound would affect the performance of responding to concurrent task.

Methods: A 3 (preview cue type) x 4 (number of abnormal patients) mixed-factorial design was adopted. Preview cue type (between-subjects) was either time-compressed speech or an abstract sound containing white noise pulses to indicate the upcoming number of abnormal patients, or no preview cue. The number of abnormal patients (within-subjects) was zero, one, two, or three.

Results: Preview cue did not improve non-clinician participants’ability to identify the location in the sequence or the vital signs of patients with abnormal vital signs. Response accuracy dropped as the number of patients with abnormal vital signs increased. The preview cue types did not affect the accuracy of responding to the concurrent task, However, the users tended to ignore the concurrent task when preview cue created by abstract sound with white noise pulses was used.

Conclusion: The current preview cue did not improve or hurt the performance of identifying abnormal patients’locations and vital signs. However, it would degrade the concurrent task performance. Therefore, the current design of preview cue can be eliminated in future auditory display design.