Tone-Grammar Interaction in the Human Brain: Mechanisms and Applications

When listening to speech, the speech melody helps us to unconsciously predict upcoming grammatical structures. Using modern medical technology, this Wallenberg Academy Fellow project will investigate the brain networks that make possible the connection between tone and grammar.

Listeners unconsciously use speech melody to prepare themselves for upcoming grammatical structures. We have previously seen how different tones in the speech melody in Swedish activate associated grammatical structures, both at the sentence and word level. Using electroencephalography (EEG), we have discovered an intriguing interaction of tonal cues affecting grammatical processing, even at the earliest stages of perception within a small fraction of a second after hearing a word. This project aims at taking this research further using cutting-edge techniques for brain imaging involving functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), and related methods currently under development at Lund University. The first aim of this long-term project is to localize the processing of tones and grammatical information as well as their interconnections in the brain. A second stage involves investigating structural change in the brain during learning of a language where tonal and grammatical information are associated. The third stage of the project will be to test whether the identified areas are necessary for processing tone-grammar associations. This stage involves testing whether persons with language problems due to lesions in the identified areas have difficulties processing structures dependent on interaction between tonal and grammatical information. A final goal is to develop novel methods for learning and rehabilitating speech melody.