Provided is a technique for grasping the biological state of a driver more accurately. The present invention comprises a means (621) for detecting phenomena that herald the onset of sleep, a means (622) for detecting phenomena that indicate the imminence of sleep, a means (623) for detecting subjective sleepiness and a low-consciousness driving state, and a means (624) for determining the level of homeostatic function, wherein said means function in parallel. Thus, each of said means can determine/detect: phenomena that herald the onset of sleep and phenomena that indicate the imminence of sleep; periods in which the driver resists subjective weak sleepiness (mild sleepiness) or strong sleepiness; or instances in which a low-consciousness driving state caused by a drop in consciousness level occurs momentarily or continues for a longer period. Thus, the driver's biological state can be determined more accurately compared to conventional art.
DEVICE FOR DETERMINING BIOLOGICAL STATE DURING DRIVING, AND COMPUTER PROGRAM