Visual mismatch negativity to change of Japanese phonetic script type

The Japanese writing system uses two phonetic scripts: hiragana and katakana. Hiragana is the most frequently used, whereas katakana is mainly used for foreign loanwords and onomatopoeias. This study examined whether differences between script types (i.e., hiragana and katakana) evoke VMMN. The ERPs were recorded for 44 participants. Hiragana and katakana were presented in the background of a visual cross-change detection task and alternately assigned as deviant (rare) and standard (frequent) scripts between blocks. In the results, P1 at the right electrode and N1 at the left electrode were significantly enhanced by hiragana rather than by katakana. In contrast, there were no significant differences between the deviant and standard conditions in P1 and N1. For both hiragana and katakana, the posterior negativity from 200 ms to 250 ms was significantly enhanced in the deviant condition compared to that in the standard condition, indicating VMMN for both scripts. These results suggested that the script-specific features of hiragana and katakana were processed before VMMN and the difference between hiragana and katakana evoked VMMN.