Brain dynamics of crosslinguistic interference resolution in Spanish-English bilinguals with and without aphasia

Bilinguals simultaneously activate both languages during word retrieval. False cognates, words overlapping in form but not meaning across languages, typically trigger crosslinguistic interference relative to non-cognates. Crosslinguistic interference resolution can be impaired in bilinguals with stroke-induced aphasia, yet little is known about the neural dynamics supporting these interference resolution processes. We recorded scalp electroencephalography in 21 age-matched controls and five bilinguals with aphasia participating in a picture-word interference paradigm eliciting crosslinguistic interference and a nonlinguistic spatial Stroop task. Bilinguals with aphasia showed lower performance than age-matched controls and crosslinguistic interference was present across both groups. A medial frontal component peaking around 400 ms post stimulus presentation was present in controls across tasks but was absent in the linguistic task in bilinguals with aphasia. This suggests that while bilinguals typically engage the medial frontal cortex to resolve crosslinguistic interference, this mechanism is disrupted in bilinguals with aphasia.