title: Acquisition and consolidation of novel morphology in human neocortex: A neuromagnetic study.
abstract: Research into neurobiological mechanisms of morphosyntactic processing of language has suggested specialised systems for decomposition and storage, which are used flexibly during the processing of complex polymorphemic words (such as those formed through affixation, e.g., boy + s = noun + plural marker or boy + ish = noun plus attenuator). However, neural underpinnings of acquisition of novel morphology are still unknown. We implicitly trained our participants with new derivational affixes through a word-picture association task and investigated the neural processes underlying formation of neural memory traces for new affixes. The participants' brain activity was recorded using magnetoencephalography (MEG), as they passively listened to the newly trained and untrained suffixes combined with real word and pseudoword stems. The MEG recording was repeated after a night's sleep using the same stimuli, to test the effects of overnight consolidation. The newly trained suffixes combined with real stems elicited stronger source activity in the left inferior frontal gyrus (LIFG) at ∼50 msec after the suffix onset than untrained suffixes, suggesting memory trace formation for the newly learned suffixes already on the same day. The following day, the suffix learning effect spread to the left superior temporal gyrus (STG) where it was again manifest as a response enhancement, particularly at ∼200-300 msec after the suffix onset, which might reflect an additional effect of overnight consolidation. Overall, the results demonstrate the rapid and dynamic processes of both immediate build-up and longer-term consolidation of neocortical memory traces for novel morphology, taking place after a short period of exposure to novel morphology and involving fronto-temporal perisylvian language circuitry.
authors.affiliation: Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Cognitive Brain Research Unit, Cognitive Science, Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland. Electronic address: alina.leminen@cfin.au.dk.
authors.forename: Alina
authors.initials: A
authors.lastname: Leminen
authors.affiliation: Cognitive Brain Research Unit, Cognitive Science, Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Lilli
authors.initials: L
authors.lastname: Kimppa
authors.affiliation: Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Cognitive Brain Research Unit, Cognitive Science, Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Miika M
authors.initials: MM
authors.lastname: Leminen
authors.affiliation: Cognitive Brain Research Unit, Cognitive Science, Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland; Department of Psychology, Åbo Akademi University, Turku, Finland.
authors.forename: Minna
authors.initials: M
authors.lastname: Lehtonen
authors.affiliation: BioMag Laboratory, HUS Medical Imaging Center, Hospital District of Helsinki and Uusimaa, Helsinki, Finland.
authors.forename: Jyrki P
authors.initials: JP
authors.lastname: Mäkelä
authors.affiliation: Center of Functionally Integrative Neuroscience, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Centre for Cognition and Decision Making, National Research University Higher School of Economics, Moscow, Russia.
authors.forename: Yury
authors.initials: Y
authors.lastname: Shtyrov
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods; D005260:Female; D006801:Humans; D007802:Language; D007858:Learning / Q000502:physiology*; D015225:Magnetoencephalography; D008297:Male; D019579:Neocortex / Q000000981:diagnostic imaging* / Q000502:physiology; D055815:Young Adult
keywords: Consolidation; Language; Learning; Magnetoencephalography (MEG); Morphology (suffix)