Modulations of the P3b effect as a function of bilingual language experience.

Recent theoretical accounts propose that variability in bilingual language experience can drive neuroplastic modifications in attentional systems. In the present study, we empirically evaluated this proposition by examining whether continuous variation in bilingual language experience predicts neural activity associated with the allocation of attention to salient environmental stimuli. To this end, we recorded electroencephalography (EEG) and response time data from young adults with diverse language backgrounds as they completed an active visual oddball paradigm known to elicit the P3b component. Language experience was quantified using composite factor scores derived from the Language and Social Background Questionnaire, which served as an index of participants' cumulative bilingual language engagement. Because childhood family socioeconomic status (SES) is known to influence neural development and adult cognitive functioning, we also controlled for childhood family SES. Although neither bilingualism nor childhood family SES was associated with behavioral performance, greater bilingual language experience was positively associated with the magnitude of the P3b effect. These findings indicate that, even after accounting for childhood family SES, lifelong bilingual language engagement may shape the neural mechanisms supporting attention allocation during dynamic stimulus tracking.