What are effective phonological units in Cantonese spoken word planning?

Two picture-word interference experiments were conducted to investigate the nature of effective phonological units in Cantonese spoken word production. The names of the pictures were Cantonese monosyllables with a consonant+vowel+consonant (CVC) structure. Participants' picture-naming responses were faster when the target (e.g., "star" /sing1/) and the distractor shared the same CVC component (e.g., /sing4/, meaning "city"), the same CV component (e.g., /sik6/, "eat"), or the same VC component (e.g., /ging2/, "region"), as opposed to when they were unrelated, and the facilitation effects observed were comparable in size. Also, similar facilitation effects were obtained across the CV+tone-related and the VC+tone-related conditions, whereas no reliable effect was found in the V+tone-related condition. These results indicate that an effective phonological unit in spoken word planning is neither a syllable (without tone) nor a segmental unit, and that the possible candidates lie between the two, at least in Cantonese.