Role of eccentricity and size in the global precedence effect

The global precedence hypothesis was investigated in a series of experiments by considering the effects of eccentricity and size and their possible interaction on the speed of processing of both global and local levels of compound stimuli. Furthermore, the possible effect of size-eccentricity uncertainty on the temporal order of processing was examined across eccentricity. The results showed a global advantage in speed of processing regardless of experimental presentation conditions when the confound of eccentricity was controlled. Somewhat surprisingly, the pattern of response times as a function of eccentricity was quadratic. Subsequent experiments indicated that the quadratic functions obtained result from the summed individual effects of size and eccentricity. The results indicate that size and eccentricity are the main determinants of the global advantage effect and that many previous findings may be explained in terms of these effects.