Relative size of global visual stimulus: advantage and interference

Absolute and relative sizes of global and local visual stimuli have been suggested as the prime determinants of the so-called global precedence effect; however, in none of these studies has the relative size of the two levels been manipulated. Difference in size seems to be the most distinct aspect of differentiating global and local levels of a visual stimulus. In this study the effect of variations in relative size of global and local levels on the global-local advantage and interference effects was examined. Analysis showed that, when the stimulus was displayed at a peripheral location, relative size was probably the prime determinant of global advantage and interference. In addition, both global and local information was processed faster when the stimulus was projected to the left visual field than to the right one. This finding was more compatible with the hypothesis of verbal-visuospatial hemispheric specialisation than with a part-whole dichotomy.