Language tonality and its effects on the perception of contour in short spoken and musical items

Two experiments investigated the effect of tonal language background on discrimination of pitch contour in short spoken and musical items. Based on the assumption that contour analysis is a domain-general process, it was hypothesized that extensive exposure to a tonal language attunes pitch feature analysis processes. Accuracy and reaction times of adult participants from tonal (Thai) and non-tonal (Australian English) language backgrounds were recorded as they discriminated intact and low-pass filtered Thai and English items that differed in rising/falling contour, and musical items that differed in rising/falling contour, major/minor interval, and contour plus interval features. As hypothesized, the tonal language group was significantly faster and more accurate at discriminating all spoken items on the basis of pitch contour; they also recorded superior reaction times in the musical context. Musical items were most easily discriminated on the basis of contour-the feature that most closely resembles pitch change in speech. The results support the contention that contour analysis is domain-general and that the early language environment fosters development of general feature extraction processes for pitch contour.