RT Journal Article SR Electronic T1 Musicianship and Prominence of Interhemispheric Connectivity Determine Two Different Pathways to Atypical Language Dominance JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP e2430232024 DO 10.1523/JNEUROSCI.2430-23.2024 VO 44 IS 37 A1 Villar-Rodríguez, Esteban A1 Marin-Marin, Lidón A1 Baena-Pérez, María A1 Cano-Melle, Cristina A1 Parcet, Maria Antònia A1 Ávila, César YR 2024 UL http://www.jneurosci.org/content/44/37/e2430232024.abstract AB During infancy and adolescence, language develops from a predominantly interhemispheric control—through the corpus callosum (CC)—to a predominantly intrahemispheric control, mainly subserved by the left arcuate fasciculus (AF). Using multimodal neuroimaging, we demonstrate that human left-handers (both male and female) with an atypical language lateralization show a rightward participation of language areas from the auditory cortex to the inferior frontal cortex when contrasting speech to tone perception and an enhanced interhemispheric anatomical and functional connectivity. Crucially, musicianship determines two different structural pathways to this outcome. Nonmusicians present a relation between atypical lateralization and intrahemispheric underdevelopment across the anterior AF, hinting at a dysregulation of the ontogenetic shift from an interhemispheric to an intrahemispheric brain. Musicians reveal an alternative pathway related to interhemispheric overdevelopment across the posterior CC and the auditory cortex. We discuss the heterogeneity in reaching atypical language lateralization and the relevance of early musical training in altering the normal development of language cognitive functions.