Visual field asymmetries in schematic persistence

A modified partial-report technique was used as a tool to study hemispheric asymmetries in schematic persistence. Two types of stimuli were presented: (1) verbal stimuli consisting of function words and nonsense words, and (2) pictures of faces and nonfaces. The stimulus items were arranged bilaterally in a circular array around the fixation point and the participants' task was to decide whether the probed item was a correct or distorted version of each stimulus type. Delay time between stimulus set and marker ranged from 0 ms to 360 ms. Calculating a sensitivity measure of accuracy, distinctive visual field differences emerged which depended on the nature of the stimuli; that is, a left field advantage for facial stimuli and a right field advantage for lexical stimuli. In addition, performance decreased linearly as delay time between probe and marker increased. The present results indicate that on a level of schematic persistence perceptual hemispheric asymmetries are already strongly present.