交通事故的發生常是因駕駛者疏忽所導致，先進安全車輛所發展之防撞警示系統可提高駕駛者注意力，以預防碰撞。近年來車內資訊系統(in-vehicle information systems, IVIS)已日益普遍，該系統所提供的資訊內容非常多樣，如前述之防撞警示資訊及駕駛者開車速度等資訊。雖然IVIS系統可提升駕駛者行車的方便性與安全，但當駕駛者使用這些系統時，他們亦有可能會因分心而導致事故發生。本研究利用駕駛模擬器探討駕駛者使用不同IVIS介面造成不同駕駛分心情況下，遇到突發狀況（如：前方車輛突然緊急煞車或在路口遇到闖紅燈車輛等）時，不同語音防撞警示系統對於駕駛反應時間之影響。本研究結果發現，影響駕駛者對突發事件反應時間之變數包括：突發事件類型、是否為第一個事件、語音防撞警示系統類型、及IVIS資訊出現時機對駕駛者干擾程度。 Traffic accidents are often caused by driver negligence. Vehicles with advanced safety features may use a collision avoidance warning system (CAWS) to help alert drivers and prevent collisions. In recent years, in-vehicle information systems (IVIS) have become a common way to provide a variety of useful information to drivers, including collision avoidance warning messages, actual driving speed and other information. These IVIS systems can enhance convenience and safety for drivers, but may also be a distraction and consequently lead to accidents. This study employs a driving simulator to explore, when drivers are distracted by different IVIS interfaces, the effects of different types of auditory collision warning messages on drivers' perception-reaction time when unexpected events occur (e.g. the preceding vehicle brakes suddenly or another vehicle runs a red light at an intersection). Our experimental findings indicate that the factors affecting drivers' perception-reaction time for unexpected events include types of events, whether an event is the first one, types of auditory collision warning systems, and the degree of interference on drivers of the timing of the appearance of IVIS messages.