title: Hippocampus activity differentiates good from poor learners of a novel lexicon.
abstract: Language proficiency is a key to academic and workplace success for native and non-native speakers. It is largely unknown, however, why some people pick up languages more easily than others. We used event-related functional magnetic resonance imaging (e-fMRI) to elucidate which brain regions are modulated during the acquisition of a novel lexicon and which of these learning-related activity changes correlated with general semantic language knowledge. Fourteen healthy young subjects learned a novel vocabulary of 45 concrete nouns via an associative learning principle over the course of five blocks during e-fMRI. As a control condition, subjects took part in a structurally identical "No-Learning" condition lacking any learning principle. Overall, increasing vocabulary proficiency was associated with (intercorrelated) modulations of activity within the left hippocampus and the left fusiform gyrus, regions involved in the binding and integration of multimodal stimuli, and with an increasing activation of the left inferior parietal cortex, the presumed neural store of phonological associations. None of these activity changes were observed during the control condition. Furthermore, subjects who showed less suppression of hippocampal activity over learning blocks scored higher on semantic knowledge in their native language and learned the novel vocabulary more efficiently. Our findings indicate that (a) the successful acquisition of a new lexicon depends on correlated amplitude changes between the left hippocampus and neocortical regions and (b) learning-related hippocampus activity is a stable marker of individual differences in the ability to acquire and master vocabularies.
authors.affiliation: Department of Neurology, University of Münster, Albert-Schweitzer-Strasse 33, 48129 Münster, Germany. caterina.breitenstein@uni-muenster.de
authors.forename: Caterina
authors.initials: C
authors.lastname: Breitenstein
authors.forename: Andreas
authors.initials: A
authors.lastname: Jansen
authors.forename: Michael
authors.initials: M
authors.lastname: Deppe
authors.forename: Ann-Freya
authors.initials: AF
authors.lastname: Foerster
authors.forename: Jens
authors.initials: J
authors.lastname: Sommer
authors.forename: Thomas
authors.initials: T
authors.lastname: Wolbers
authors.forename: Stefan
authors.initials: S
authors.lastname: Knecht
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology; D001288:Attention / Q000502:physiology; D001931:Brain Mapping; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006624:Hippocampus / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007802:Language; D007859:Learning Disabilities / Q000175:diagnosis / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000503:physiopathology; D010153:Paired-Associate Learning / Q000502:physiology; D010296:Parietal Lobe / Q000503:physiopathology; D010364:Pattern Recognition, Visual / Q000502:physiology; D012016:Reference Values; D012153:Retention, Psychology / Q000502:physiology; D012660:Semantics; D014706:Verbal Learning / Q000502:physiology*; D014825:Vocabulary