Visually guided collision avoidance and collision achievement

To survive on today's highways, a driver must have highly developed skills in visually guided collision avoidance. To play such games as cricket, tenn is or baseball demands accurate, precise and reliable collision achievement .. This review discusses evidence that some of these tasks are performed by predicting where an object will be at some sharply defined instant, severa l hundred milliseconds in the future, while other tasks are performed by ut ilizing the fact that some of our motor actions change what we see in ways that obey lawful relationships, and can therefore be learned. Several monoc ular and binocular visual correlates of the direction of an object's motion relative to the observer's head have been derived theoretically, along wit h visual correlates of the time to collision with an approaching object. Al though laboratory psychophysics can identify putative neural mechanisms by showing which of the known correlates are processed by the human visual sys tem independently of other visual information, it is only field research on , for example, driving, aviation and sport that can show which visual cues are actually used in these activities. This article reviews this research a nd describes a general psychophysically based rational approach to the desi gn of such field studies.