AGE-CHANGES IN THE MISSING-LETTER EFFECT REFLECT THE READERS GROWING ABILITY TO EXTRACT THE STRUCTURE FROM TEXT

Readers searching for a target letter in text are more likely to miss it in frequent function words than in less frequent content words, and the magnitude of this effect increases with age. While this increase has been taken to indicate that proficient readers process familiar wo rds in terms of larger orthographic units, we propose that it reflects the reader's growing ability to extract the structure of text, result ing in a reduced emphasis on function than on content words. Indeed, c omparing 2nd graders (7 to 7 1/2 years) and college students (Experime nt 1) this increase was found even when function and content words wer e equated for frequency. Scrambling words within a sentence (Experimen t 2) improved letter detection in function compared to content words a mong 7th graders (12 to 13 years) and college students, but not among 3rd graders (8 to 9 years). Although letter detection was also affecte d by word frequency, the age differences noted above are possibly due not to the increasing familiarity of words, but rather to the growing sensitivity to their structural role in text, (C) 1998 Academic Press.