Priming Effects of Tones in Visual Processing of Vietnamese

This paper presents an experiment to detect the presence of visual tonal priming in Vietnamese. We carried out a lexical decision task with masked priming with 23 Native speakers of Vietnamese. We compared the reaction times of (i) identical primes and targets, which share consonants, vowels and tones, (ii) primes/targets with different tones, which share only the consonants and vowels, and (iii) completely unrelated primes/targets, where no elements are shared. Prime-target pairs with shared consonants and vowels but different tones had significantly faster RTs than unrelated prime-target pairs (645 vs. 674 ms, p<0.05). This means that consonants and vowels produce a facilitation effect. We also found that prime-target pairs with shared consonants and vowels but different tone have significantly slower RTs than identical prime/targets (645 vs. 622 ms, p<0.05). This is evidence that tones provide facilitation separate from that of segments. Several hypotheses can explain this pattern: This could be an effect of visual similarity of tonal diacritics in the prime/targets, or it could be related to the Vietnamese writing system. The explicit and stable tonal marking in Vietnamese writing, which is unavailable in Mandarin, Cantonese, Thai – languages for which tonal priming is elusive – might result in greater tonal metacognition and stronger priming effects.