Reaction time for global and local identification of small-large composite letters presented in different orientations.

Eight men and eight women were timed as they made judgments about a large capital letter F composed of small versions of the same letter. The subjects were asked to indicate by manual key-pressing responses whether either the large letter (global identification task) or the small letters (local identification task) were normal or reflected letters. With both the large and small letters always in the same orientation but sometimes conflicting in their normal-reflected aspect, the letters were presented in six different angular orientation. Analysis showed that reaction time (RT) (1) increased in relation to the deviation of the letters from standard upright, (2) was slower when both small and large letters were reflected than when both were normal, and (3) was faster for the global than for the local identification task when the letters were completely inverted. The study provided only qualified evidence that global identification of the normalness-reflectedness of letters occurs more quickly than local identification of this attribute.