Influence of the target delay and duration on the prediction of a moving stimulus future position.

In a linear-motion prediction study an immobile target with different duration and delay with respect to the onset of the visible motion determined the motion extrapolation distance. The subject's task was to press a key at the moment when the moving stimulus would reach the position of the target if it continued its motion on the screen. The subject's response time was measured between the moment of the moving stimulus disappearance and the moment of key pressing. A linear relationship between the response time and the concealment time was obtained under all experimental conditions. It was demonstrated that the duration of the target did not affect the linear regression equation constants. The delay of the target presentation with respect to the onset of the visible motion was found to influence the free term of the linear relationship. When the target was presented with a great delay (0.56 s before the moving stimulus disappearance) the intercept in the linear relationship significantly decreased. The present results suggest that the organization of the response in the motion prediction conditions influences the temporal characteristics of the subject's performance. This influence is manifested in alternation of the free term in the linear relationship between the response time and concealment time.