Shona Lexical Tone Processing: the Effect of Brain Damage and Linguistic Experience on Language Production and Perception

This dissertation investigates the production and perception of Shona lexical tone at the disyllabic level. The focus is two fold; i) the effect of brain lesions on the production and perception of lexical tone, ii) the influence of linguistic experience with pitch contrasts on the ability to perceive Shona lexical tone with an emphasis on the strategies used to distinguish lexical tones. The dissertation evaluates the currently available hypotheses on the lateralization of lexical tone (Van Lancker, 1980; Van Lancker & Sidtis, 1992) to account for the patterns seen in Shona brain damaged patients. The second part of the dissertation examines the effect of linguistic experience on lexical tone processing focusing on the strategies underlying the performance of three groups: neurologically intact Shona, Thai and German listeners, and also the effect of increasing phonetic contrasts on the performance of the listeners. The aim here is to examine the perceptual ability of healthy native and non-native speakers of languages that use pitch phonemically at the syllable level (Thai & Shona) and/or at the sentential level (German).