[Brain mappings in non-fluent late Chinese-English bilinguals]

To discuss the distribution characteristics of language areas in Chinese-English non-fluent late bilinguals.

Six Chinese-English bilinguals with eloquent tumors underwent awake-surgeries. The activated areas of BOLD-fMRI were obtained as the patients performed pure naming, verb generation, and abstract/concrete judgment tasks. Direct cortical stimulation(DCS) as the golden standard of language mapping were performed during awake-surgeries on the exposed cortical areas. BOLD-fMRI results of 3 language tasks were compared with DCS results. The statistical method was McNemer.

Sixteen positive sites(22.5%) were comfirmed out of 71 stimulations. There were 3 specific language sites, in which 2 sites were specific English sites and 1 site was specific Chinese site. When activated areas of BOLD-fMRI were compared with the DCS results, verb generation task had the highest concordance rate 40.9% (95%CI:30.2%-52.5%) . There were significant differences between the results of BOLD-fMRI and DCS of all 3 bilingual tasks(P < 0.017).

There are specific language areas in Chinese-English non-fluent late bilinguals. The BOLD-fMRI language mapping could not substitute DCS in the context of mapping language areas in bilinguals.