Causal analysis between vehicle operating data and physiological responses

The objective of this paper is to clarify the interrelation between vehicle operating data and physiological responses to different psychological states. Multidimensional directed coherence (MDC) analysis was applied to the human–machine system, as observed by vehicle operating data and physiological indices to reveal the mechanism of the interrelation. The MDC analysis is one way to visualize the information flow between an arbitrary number of time series signals in the frequency domain. As a result, it was found that the entrainment of physiological indices on vehicle operating data is different depending on the cognitive resources devoted to driving motion. In particular, it was clarified that driving motion is easily influenced by physiological indices when the cognitive resources devoted to driving motion are few either absolutely or relatively.