Psychophysiological Assessment of Acute Stress Induced by High-Pressure Law-Enforcement Driving: A Pilot Study

Psychophysiological stress may affect safety of police officers (PO) driving in emergency situations. Although vehicle-related incidents are the most frequent cause of line-of-duty casualties, methods to quantify individual stress under critical law enforcement (LE) driving are still undefined. We report successful monitoring of multiple psychophysiological parameters of five PO under training as instructors in high-pressure LE driving tasks. The driving tasks included physical, mental and combined stress. Baseline psychological evaluation was normal, with no individual tendency to respond with abnormally high levels of state-anxiety to the test challenges. The majority of heart rate variability (HRV) parameters, analyzed in the time-domain, frequency-domain and with non-linear (NL) methods, were significantly different (p <.0001) between baseline and driving. Linear Discriminant Analysis of significant NL parameters provided differentiation between driving stressors with 90% accuracy. Preliminary results demonstrate the reliability of HRV analysis to distinguish complex psychophysiological stress reactions induced by realistic high-pressure LE driving.