The cognitive processing of Japanese loanwords in katakana

The present study examined two questions concerning the cognitive processing of Japanese loanwords borrowed from English and written in katakana. The rst question was whether “interlexical activation” occurs between Japanese and English. Results from a lexical decision task showed that loanwords phonetically similar to the original English words were judged with the same speed and accuracy as those being phonetically dissimilar to their original English words. The study further examined the cognitive processing of unadopted loanwords (i.e., words unlisted in a Japanese loanword dictionary). Reaction times displayed the shortest mean for non‐words, followed by pseudo‐loanwords, and nally unadopted loanwords. Thus, the only time the lexical representation of an original English word was possibly activated was when native Japanese speakers had seldom seen the word in katakana. The second question was what creates the “lexical mental boundary” between adopted and unadopted loanwords. A questionnaire showed that native Japanese speakers are likely to use decision‐making strategies for determining lexicality of loanwords in Japanese based on their daily experience of exposure to katakana words in print.