Blank characters in tachistoscopic recognition: Space has both a symbolic and a sensory role.

In a free-recall tachistoscopic task, increased letter spacing reduces the advantage of familiar pseudo-words over random letter strings. To explore this phenomenon, 2 ways of introducing "extra" space between letters were compared in 2 experiments involving 69 undergraduates. Using both a partial-report bar-probe task and a free-recall task, letter spacing was increased by (1) spreading normally sized material over a wider visual angle and (2) reducing letter size while holding the retinal position constant. In free recall, the space between letters relative to their height controlled performance by altering the size of the familiarity effect. In the probe task, however, accuracy of report depended on letter size, and the familiarity effect was independent of the size and spacing manipulations. Thus, in free-recall, the space between letters served as a blank character, but in the partial-report task, visual resolution controlled performance. (French abstract) (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)