Poster A6, Thursday, August 16, 10:15 am – 12:00 pm, Room 2000AB
Neuroanatomical Correlates of Foreign Speech Production in Musician and Non-Musician Bilinguals
Paul-Noel Rousseau1,4, Lucía Vaquero2,3, Virginia Penhune2,4, Denise Klein1,4;1McGill University, 2Concordia University, 3University of Barcelona, 4CRBLM - The Centre for Research on Brain, Language and Music
Music and language have been shown to share a similar neural architecture, and there is evidence of transfer from musical training to different aspects of language ability. Using a combination of behavioural testing and structural neuroimaging we sought to tease apart this relationship and evaluate the neuroanatomical correlates of foreign language ability in a group of musician and non-musician bilinguals. 61 subjects (31 musicians, 30 non-musicians) were recruited and administered a battery of behavioural tests consisting of cognitive, music, and foreign language tasks. The language tasks were comprised of a perception task involving the discrimination of Hindi dental/retroflex phonemes, production of Hindi words, and production of syllables and words including the Farsi voiced uvular stop. We also collected T1 structural imaging, and performed a cortical thickness analysis in order to assess the anatomical correlates foreign language abilities. Behaviourally, we observed no differences between the musician and non-musician groups on any of the foreign language tasks. Musicians, did however, outperform non-musicians on a range of cognitive tests. In the cortical thickness analysis, we found performance on the Hindi production task be to be correlated with cortical thickness in the left inferior frontal gyrus, left somatosensory cortex, left medial temporal lobe, and right supramarginal gyrus and somatosensory cortex. Performance on the Farsi production task was correlated with cortical thickness in the left inferior frontal gyrus and medial temporal lobe as well as right posterior superior temporal gyrus and bilateral middle temporal gyri. We did not observe any significant differences in cortical thickness between groups, nor did we observe any relationship between structure and performance on the discrimination task. We found no evidence of transfer from the musical domain to language, however musical training was related to better performance on a range of cognitive tests. The anatomical correlates of the foreign language production tasks did not differ between the groups, suggesting a shared architecture underlying their performance. While both the Hindi and Farsi tasks were related to cortical thickness in the left IFG, the former showed a greater contribution the somatosensory cortices and the later the middle temporal gyri. This implies that the different language tasks may involve different underlying abilities and consequently different parts of the brain. The lack of transfer effects may be due to a similar advantage in foreign language perception and production from bilingualism, to which music experience may not add a substantial advantage. However, only the comparison with monolingual musicians or non-musicians would help us shed light on this issue in future studies.
Topic Area: Speech Motor Control and Sensorimotor Integration