Poster B51, Tuesday, August 20, 2019, 3:15 – 5:00 pm, Restaurant Hall
Speech production in second language learners of Russian
Mara Flynn1, Yanyu Xiong1, Sharlene Newman1;1Indiana University Bloomington
This study investigated fMRI measured brain activation during reading/speech planning and discourse production in participants’ L1 (English) and L2 (Russian). During the study participants watched short, silent animated videos after which they read questions about the videos (e.g., “Why does the cat want the man to wake up?”), and provided verbal responses. A total of 4 experimental runs (2 for each language) were presented. Participants were instructed as to which language the questions would be written in and the language they were to produce prior to each run. The questions were designed to require responses longer than a few words, and subjects were instructed to respond in full sentences. The two phases of interest were planning (which includes reading the question and formulating a response) and production. The results revealed greater activation for L2 than L1 for both the planning/reading and production phases. During the planning/reading phase increased activation for Russian was observed in regions linked to orthographic and phonological processing as well as the orbitofrontal cortex (OFC). Russian also elicited increased activation in right inferior occipital-temporal regions, which is consistent with more effort required to read the less familiar Russian orthography. Russian production elicited increased activation in the OFC, right inferior occipital-temporal region and medial occipital/parietal cortex. The increased activation in inferior occipital-temporal regions suggests that subjects may visualize Russian words to aid in production. The results obtained also speak to the engagement of cognitive control regions. In previous studies of bilingualism regions such as the dorsal anterior cingulate, supplmentary motor area, or basal ganglia have been found to be involved (Rossi et al., 2018). However, those regions were not observed here. It may be because the current study had the languages blocked and required discourse or sentence production; therefore, the type of control processes required in the current study may be different that previous studies. The OFC has long been associated with using information about the task/situation to exert inhibitory control to reduce impulsive responses (Rudebeck & Rich, 2018). A more recent theory is that the OFC represents a cognitive map of the task space which is used to, in the case of speech production, make decisions about how to respond to questions including which words to use (Schuck et al., 2016). The findings presented demonstrate the need to examine sentence and discourse production in L2 learners. Rossi, Eleonora, Sharlene Newman, Judith F. Kroll, and Michele T. Diaz. "Neural signatures of inhibitory control in bilingual spoken production." Cortex 108 (2018): 50-66. Rudebeck, P. H., & Rich, E. L. (2018). Orbitofrontal cortex. Current Biology, 28(18), R1083-R1088. Schuck, N. W., Cai, M. B., Wilson, R. C., & Niv, Y. (2016). Human orbitofrontal cortex represents a cognitive map of state space. Neuron, 91(6), 1402-1412.
Themes: Multilingualism, Language Production
Method: Functional Imaging