Objective: The effects of talker sex and voice style of verbal cockpit warnings on performance were investigated to help make warning messages distinct from speech on the flight deck. Background: Auditory warnings are used in aircraft to alert the crew to hazards and their associated levels of danger. Failing to comply with a warning has led to aviation incidents and accidents. Methods: Participants were required to monitor the auditory channel and identify the verbal warning while simultaneously performing a visual pursuit tracking task. A male and a female actor annunciated the warning words in three styles: monotone, urgent, and whisper. In Experiment 1, warning words were presented in quiet, and in Experiment 2, they were presented in a background of speech babble that simulated cockpit radio communication. Results: Experiment 1 showed that the monotone and urgent styles resulted in the fastest identification response time (RT) regardless of the talker and listener's sex. Experiment 2 showed that the male talker annunciating in either the monotone or the urgent style resulted in the largest proportion correct and fastest identification RT regardless of the listener's sex. Both experiments showed effects of word semantics on performance. Conclusion: Effective use of speech parameters and word semantics can increase the saliency of verbal cockpit warnings. Application: Potential applications of this research include improving the attention-getting capability of an alerting system, which could lead to increased warning compliance, potentially resulting in fewer incidents and accidents.
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