Expiratory Threshold Loading and Attentional Performance.

Area of Science:

• Human Factors
• Aerospace Medicine
• Cognitive Psychology

Background:

• Pilot attentional performance is crucial for flight safety.
• The work of breathing, particularly expiratory effort, may act as a distraction stimulus.
• Fighter pilots experience increased expiratory work of breathing.

Purpose of the Study:

• To investigate the impact of increased expiratory pressure-time product on attentional performance.
• To determine how expiratory effort sensation affects attentional performance.
• To assess the influence of altered end-tidal gases on a continuous performance task.

Main Methods:

• Ten healthy participants completed a modified Masked Conjunctive Continuous Performance Task.
• Participants breathed against four different expiratory threshold loads.
• Repeated measures ANOVA and generalized additive mixed effects models were employed.

Main Results:

• Increased expiratory threshold loads significantly lengthened overall median hit reaction times.
• Higher expiratory effort sensation correlated with longer reaction times and increased omission error rates.
• Commission error rates were not significantly affected by increased expiratory effort sensation.

Conclusions:

• Progressively greater expiratory threshold loads during spontaneous breathing can impair attentional performance.
• Expiratory effort sensation negatively impacts reaction times and increases stimuli recognition errors.
• Findings suggest a potential mechanism for attentional deficits in pilots due to breathing resistance.