A test of letter configuration coding in visual word recognition

Most models of word recognition assume that a letter's identity and position are conjointly encoded. This means that in words with repeated letters (e.g. "radar"), each instance of the same letter is coded as a separate object. Here we tested an alternative scenario, according to which the brain employs configurational representations (e.g. recognition of three units in the configuration 12321 activating "radar"). Such representations explain why one sees similarities between "radar" and "tenet", and would offer an efficient way to compute letter repetitions. In two experiments, target word recognition was tested as a function of different-symbol primes that were configurationally congruent ("kgegk"- "radar") or not ("kggke"- "radar"). We reasoned that if the brain indeed engages configuration codes, congruent primes should facilitate target recognition compared to incongruent primes. However, Bayesian statistical analyses provided strong evidence for the null-hypothesis. We surmise that the brain does not engage configuration codes in word recognition.