Is pitch accent necessary for comprehension by native Japanese speakers? – An ERP investigation

• This paper provides the first ERP evidence showing a minor role for pitch accent when processing Japanese sentences.
• An N400 was obtained when a word was semantically incorrect for a given context but not for incorrectly accented homophones.
• Pitch accent itself may not be an essential factor during language comprehension.

Not unlike the tonal system in Chinese, Japanese habitually attaches pitch accents to the production of words. However, in contrast to Chinese, few homophonic word-pairs are really distinguished by pitch accents (Shibata & Shibata, 1990). This predicts that pitch accent plays a small role in lexical selection for Japanese language comprehension. The present study investigated whether native Japanese speakers necessarily use pitch accent in the processing of accent-contrasted homophonic pairs (e.g., ame [LH] for ‘candy’ and ame [HL] for ‘rain’) measuring electroencephalographic (EEG) potentials. Electrophysiological evidence (i.e., N400) was obtained when a word was semantically incorrect for a given context but not for incorrectly accented homophones. This suggests that pitch accent indeed plays a minor role when understanding Japanese.