Blanco, B. 1 , Molnar, M. 1 , Carreiras, M. 1, 2, 3 & Caballero-Gaudes, C. 1
1 Basque Center on Cognition, Brain, and Language (BCBL), Donostia, Spain
2 IKERBASQUE. Basque Foundation for Science, Bilbao, Spain
3 University of the Basque Country, UPV/EHU, Spain
Resting state functional connectivity (RSFC) networks reflect synchronized spontaneous activity of spatially distant areas in the human brain and are essential to understand the intrinsic relationship between brain regions that are functionally related in adults and infants. In this work, we investigate if the presence of long-term environmental factors such as the exposure to two languages at early age could lead to changes in these networks. A 52-channel near-infrared spectroscopy (NIRS) system was used to measure spontaneous cortical activity in 4-month-old monolingual (N=11) and bilingual infants (N=17). Correlation coefficients for the time course of oxygenated haemoglobin signal were determined to construct the connectivity matrix for each participant. Potential significant connections present in each group and differences in the connectivity patterns between groups were examined by means of parametric and non-parametric permutation statistical methods. Network metrics of intrahemispheric and interhemispheric connectivity were also evaluated. Our results for bilingual infants showed a large number of intrahemispheric and interhemispheric connections especially over frontal and temporal regions, while monolinguals showed less connections and a different connectivity pattern with most connections being localized in frontal and occipital regions. This suggests that early and continued exposure to a bilingual environment might require the participation of additional brain areas and that this extra activation might influence the configuration and the development of resting state functional brain networks.