Is red alert always optimal? An empirical study on the effects of red and blue feedback on performance under excessive stress

Abstract

Background

In critical situations, a pilot’s ability to recognize and adjust excessive stress levels is vital for risk mitigation, especially in single pilot operations where self-awareness is crucial. Research on monitoring and feedback for excessive stress is limited, and few studies have examined how visual feedback from display interfaces can enhance pilot performance. Traditional alert interfaces predominantly use red feedback, but the unique cognitive characteristics associated with excessive stress may lead to negative outcomes when red feedback is employed. Therefore, it is essential to investigate the effectiveness of feedback under these conditions.

Methods

This study utilized the MATB (Multi-tasking Ability Task Battery), an effective abstract flight task experimental prototype with stress inducing in participants through the TSST (Trier Social Stress Test) paradigm. The categories of stress were assessed using the Yerkes-Dodson Law. Audio signal was used to train a Probabilistic Neural Network (PNN) model for real-time discrimination of excessive stress levels, providing participants with one of three types of visual feedback: no feedback, red feedback, or blue feedback. The experiment was designed with an within-subjects approach, involving 20 participants.

Results

There were no significant differences in primary task performance. However, secondary task performance was significantly poor under red feedback compared to blue feedback. Additionally, there were no significant differences between red feedback and no feedback conditions.

Conclusion

This study suggests that feedback for excessive stress should take into account its unique characteristics, recommending caution in the use of red alerts. The findings provide valuable insights for future human–computer interface design.