Task difficulty, risk, effort and comfort in a simulated driving task--Implications for Risk Allostasis Theory

Area of Science:

• Psychology
• Human-Computer Interaction
• Transportation Engineering

Background:

• Risk Allostasis Theory posits drivers maintain a preferred risk range.
• Previous studies used video clips to assess driver risk perception.
• Task-Difficulty Homeostasis theory is a precursor to Risk Allostasis Theory.

Purpose of the Study:

• To investigate Risk Allostasis Theory using a driving simulator.
• To explore the relationship between task difficulty, risk, effort, comfort, and habit.
• To determine if a linear trend or threshold effect governs driver risk perception.

Main Methods:

• Participants controlled a vehicle in a driving simulator.
• Subjective ratings of task difficulty, risk, effort, and comfort were collected.
• Driving simulator provided enhanced speed cues and active control compared to video clips.

Main Results:

• Task difficulty and perceived risk are related, as are effort and comfort.
• A linear trend was not observed; instead, a threshold effect was found.
• Ratings of risk, difficulty, effort, and comfort remained stable until a certain threshold was reached.

Conclusions:

• Driver behavior aligns with a threshold model, not a linear one.
• Drivers prefer operating within a stable range of low subjective risk and difficulty.
• Driving simulators offer a more dynamic environment for studying driver behavior than passive video observation.