University Archives

INTRODUCTION. About 18 % of fatal vehicle crashes involve a drowsy driver (AAAFTS, 2024). Physiological markers such as drowsiness and microsleep episodes can be monitored to mitigate driver inattentiveness. The objective of the present work was to determine the utility of location-invariant single-lead electrode devices for monitoring fluctuations in attentiveness. For such devices to be practical, it is important to determine what spectral band power (alpha, theta) is most invariant to hemispheric placement. METHOD. Monotonous driving in a desktop simulator was used to induce fluctuations in attentiveness.  Under night driving conditions, participants drove for 30 minutes on cruise control on a traffic-free, monotonous highway.  Continuous EEG was recorded from two active prefrontal sites (Fp1 and Fp2). We calculated alpha and theta power in 30-second epochs over the 30 minute drive. For now, we report data for six participants. RESULTS. The strength of association between left and right hemispheres was stronger for theta power fluctuations (R2 = .61) than alpha power fluctuations (R2 = .46). A Bayes Factor was calculated to compare a 'theta-is-better' model which hypothesized a stronger left-right association for theta than for alpha power fluctuations, against the null hypothesis. The ratio of 5.7 indicated that the data from the six drivers were 5.7 times more likely under the 'theta-is-better' model than under the null model.  CONCLUSION. We demonstrated that left and right fluctuations are more similar for theta than alpha activity. Consequently, fluctuations in theta may be optimal for location-invariant, single-lead electrode devices designed to monitor attentiveness.