title: Language lateralisation in late proficient bilinguals: a lexical decision fMRI study.
abstract: Approximately half the world's population can now speak more than one language. Understanding the neural basis of language organisation in bilinguals, and whether the cortical networks involved during language processing differ from that of monolinguals, is therefore an important area of research. A main issue concerns whether L2 (second language) is processed using the same neural mechanisms that mediate L1 (first language) processing. Moderating factors include the age of L2 acquisition and the level of proficiency. Here we used a lexical decision task with five conditions during functional magnetic resonance imaging (fMRI) to investigate language processing in eight late proficient bilinguals when using Macedonian (L1) and English (L2). Bilinguals had greater bilateral activation during both L1 and L2 processing, and therefore weaker language lateralisation, compared to matched control English monolinguals. A greater amount of overall activation was also seen in bilinguals, especially during L2 conditions. Late proficient bilinguals living in their L2 environment employ a more extensive neural network than monolinguals when processing their second language.
authors.affiliation: Research Centre for Cognitive Neuroscience, Department of Psychology, The University of Auckland, Auckland, New Zealand.
authors.forename: Haeme R P
authors.initials: HR
authors.lastname: Park
authors.forename: Gjurgjica
authors.initials: G
authors.lastname: Badzakova-Trajkov
authors.forename: Karen E
authors.initials: KE
authors.lastname: Waldie
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply* / Q000502:physiology*; D003657:Decision Making; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D019303:Multilingualism; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen