Chronos is a powerful new USB-based response and stimulus device for accurate collection and verification of tactile, auditory, visual, and analog response timing along with the precise source of audio and generic analog output timing. Chronos features sub-millisecond accuracy and consistent sound output latencies across machines. Chronos includes 16 digital inputs and 16 digital outputs, eliminating the need for a parallel port. All responses collected are synchronous to the E-Prime® time domain. Multiple Chronos devices can be connected to a single PC.