The Effects of Cell Phone Use and Automation on Driver Performance and Subjective State in Simulated Driving

Abstract

Cell phone use has been identified as a threat to driver safety. Impairments may depend on the type of cell phone usage such as calling back and text messaging. The present study investigated whether the impact of phone use depends on the state of fatigue of the driver. A manipulation of full vehicle automation was used to induce a state of passive fatigue during a simulated drive. Participants were also assigned to one of four cell phone response conditions (Cell Phone, Text Message, Free-Choice or Control). Subjective responses, vehicle control and speed of response to an emergency event were assessed. Cell phone use did not mitigate stress and fatigue produced by vehicle automation. We also replicated existing findings that phone use, especially texting, impairs normal driving performance. However, phone use during automation was associated with a faster braking response following transition to normal control, suggesting that there may be circumstances under which phone use enhances alertness. Safety implications of the findings are discussed.