Acquisition of categorical perception of Mandarin tone

Abstract

This experiment examined the effect of motor repetition on the learning of Mandarin pitch categories by non-native speakers. In Mandarin, there are four tonal categories, which refer to pitch contours that discriminate words. Differentiating tonal categories is both essential and arduous for non-native speakers to learn. Native speakers do this effortlessly because they have a categorical perception (CP) effect for tones, i.e. they perceive items within a tonal category as more similar to each other and items between categories as more different. Non-native speakers do not have this effect, and this experiment attempted to induce the CP effect for Mandarin tones via a training task, which was the experimental manipulation: Participants either repeated a tone stimulus before categorizing it or listened to a stimulus and categorized it without repetition. Discrimination between and within tonal categories was measured before and after training. All participants demonstrated increased between-category and within-category discrimination after training, except for learners who repeated stimuli in the training phase. They demonstrated a decrease in within-category discrimination, showing a weak CP effect that could be stronger with more training. Implications of these results on auditory category learning and language education will be discussed.