Interference effect caused by repetition in visual recognition of letters: Examination of the orthographic difference between two same letters

Abstract

The present study examined the effect of phonological identity between two letters on the visual recognition of the letters. Participants were required to identify the two same or different letters that were successively presented for a short duration. In order to manipulate the phonological identity of the two letters, the orthography of the Kana letters was varied. In half of the trials, the first and second letters were presented in Hiragana (the same-orthography condition). In the other half, the first letter was presented in Katakana, and the second letter in Hiragana (the different-orthography condition). The results revealed that the identification performance for the second letter was reduced in the same-orthography condition when the two letters were the same, compared with when they were different. In contrast to this, in the different-orthography condition, the identification performance of the second repeated letter was marginally superior to that of the nonrepeated letter. Considering the present findings together with those of the author's previous study (Kuwana, 2004), it is suggested that the interference effect caused by repetition could result from the reduction in the availability of visual pattern information stored in long-term memory. © Japanese Psychological Association 2007.