Transient selective aphasia in highly proficient bilinguals triggered by electrical stimulation of the left superior temporal gyrus

• DOI: 10.1007/s00701-025-06508-5
• Publication Date: 2025-04-05T22:42:05Z
• Authors: Ileana Quiñones; Sandra Gisbert-Muñoz; Garazi Bermudez; Iñigo Pomposo; Santiago Gil Robles; Manuel Carreiras; Lucia Amoruso
• Keywords: Angular gyrus; Superior temporal gyrus; Fusiform gyrus

Abstract Are an individual’s first (L1) and second (L2) languages represented in shared or distinct brain territories? Using intraoperative electrical stimulation mapping (ESM) in two Basque-Spanish bilinguals with non-growing lesions—thus avoiding confounding effects of adaptive plasticity—this study identified distinct language representations within the left temporal lobe. Stimulation of posterior and anterior superior temporal gyri induced language-selective aphasias, whereas stimulation of the mid-temporal region and inferior fronto-occipital fasciculus produced naming errors without language specificity. These findings highlight both shared and distinct loci for L1 and L2, advancing our understanding of bilingual brain organization.