German capitalization of nouns and the detection of letters in continuous text

The missing-letter effect refers to the phenomenon that letters are more difficult to detect in common function words (such as the) than in content words. Assuming that the missing-letter effect is diagnostic of the extraction of text structure, we exploited a special feature of German - the convention to capitalize the initial letter of nouns. Given the great flexibility of word order in German, it was proposed that this convention might help readers specify the structure of the sentence. Therefore orthographic variations that violate the capitalization rules should disrupt structure extraction and should result in a reduced missing-letter effect. The results indicated that: 1) capitalization of function words eliminated the missing-letter effect, hut not at the beginning of a sentence; 2) A missing-letter effect occurred when the capitalization of the first letter was correct, but was followed by typecase alternation, and also when the size of the initial letters was relatively large for function words, but relatively small for content words. The results were discussed with respect to the possible contributions of visual familiarity, structural role, and processing time to the missing-letter effect, taking into account that a capitalized initial letter conveys significant information about the word class for German readers. Thus, the present results indicate that readers take advantage not only of function words but of any other information (here the capitalization of nouns) that helps to extract the structure of a sentence.