The persistence of position

I describe a signal coined position persistence that stores information about the last seen position of an object. Position persistence is not the same as visible persistence, although some of its properties are similar. The duration of position persistence is such that objects visible briefly always generate a position signal for at least 180 ms. The signal is not affected by the intensity of the object, nor of the background. Position persistence decreases with increasing speed, but does not depend on retinal eccentricity. Finally, the persisting signal is not tightly bound to the object that causes it. The signal contains no information on the colour of the object, whereas shape information may become represented after approximately 100 ms. The existence of this signal is interpreted as a psychophysical signature of the parallel processing of visual information.