Does Traffic Stress Affect Distance Estimation and Recognition Accuracy in Urban Bus Drivers?

Area of Science:

• Occupational Health
• Psychophysiology
• Transportation Safety

Background:

• Traffic load is a significant factor influencing driver stress and performance.
• Adrenaline levels serve as a physiological indicator of stress in response to environmental demands.
• Urban bus drivers face unique challenges due to high traffic volumes and passenger safety responsibilities.

Purpose of the Study:

• To investigate the relationship between traffic load, adrenaline levels, and cognitive performance in urban bus drivers.
• To assess the impact of heavy versus low traffic conditions on drivers' stress responses and their accuracy in distance estimation and object recognition.
• To understand how physiological stress indicators correlate with functional driving abilities.

Main Methods:

• A study involving 69 urban bus drivers was conducted, comparing performance and physiological measures on heavy-traffic and low-traffic days.
• Blood samples were collected to measure adrenaline hormone levels, serving as a stress index.
• Cognitive functions, specifically distance estimation precision and recognition accuracy, were evaluated under both traffic conditions.

Main Results:

• Drivers exhibited significantly higher blood adrenaline levels on heavy-traffic days compared to low-traffic days.
• Recognition accuracy and distance estimation precision were notably lower on high-traffic days.
• A correlation was observed between increased adrenaline levels and decreased performance in key driving-related cognitive tasks.

Conclusions:

• Increased traffic load elevates stress levels in urban bus drivers, as indicated by higher adrenaline.
• Elevated stress negatively affects drivers' judgment, reducing their precision in distance estimation and recognition accuracy.
• Findings suggest a need for strategies to mitigate stress and maintain cognitive function in drivers operating under demanding traffic conditions.