Reaction time testing is made easy with the PVT-192. The literature has shown that simple reaction time is a convenient and sensitive continuous performance test for long-term, large-scale testing of vigilance, effects of sleep deprivation, and drug effects. The PVT test, combined with easy-to-use REACT software, has proven to be a valuable tool wherever measures of performance or sleepiness effects are needed. These include the transportation and pharmaceutical industries.  This is the same device used in published literature Bibliography with high-resolution, accurate timing, calibrated buttons and stimulus (visual and/or auditory) which supports multiple stored tests on the device using a wide range of test lengths.