Masked form priming as a function of letter position: An evaluation of current orthographic coding models

A word’s exterior letters, particularly its initial letter, appear to have a special status when reading. Therefore, most orthographic coding models incorporate assumptions giving initial letters and, in some cases, final letters, enhanced importance during the orthographic coding process. In the present paper, three masked priming experiments were carried out, using the conventional lexical decision task, the sandwich priming lexical decision task and the masked priming same-different task, in an attempt to examine a number of those models with a specific focus on the implications of the models’ assumptions concerning the different letter positions. The related primes andtargets were six-letter strings that differed in two letter positions, initial (e.g., jnckeyHOCKEY ), middle (e.g., hojney-HOCKEY ) or final ( hockjn-HOCKEY ), with the middle-letters different primes being the primes that maintained both end letters. To the extent possible, the predictions of the models were derived by using easyNet, the simulation program recently developed by Adelman, Gubian and Davis (in preparation). In all experiments, the final-letters different primes were the most effective primes with there being no clear distinction between the other two prime types, a pattern that none of the models predicted. The lack of an advantage for the middle-letters different primes suggests that the orthographic code driving masked priming is not one that places a special emphasis on the identities of the exterior letters.