title: Abnormal functioning of the left temporal lobe in language-impaired children.
abstract: Specific language impairment is associated with enduring problems in language-related functions. We followed the spatiotemporal course of cortical activation in SLI using magnetoencephalography. In the experiment, children with normal and impaired language development heard spoken real words and pseudowords presented only once or two times in a row. In typically developing children, the activation in the bilateral superior temporal cortices was attenuated to the second presentation of the same word. In SLI children, this repetition effect was nearly nonexistent in the left hemisphere. Furthermore, the activation was equally strong to words and pseudowords in SLI children whereas in the typically developing children the left hemisphere activation persisted longer for pseudowords than words. Our results indicate that the short-term maintenance of linguistic activation that underlies spoken word recognition is defective in SLI particularly in the left language-dominant hemisphere. The unusually rapid decay of speech-evoked activation can contribute to impaired vocabulary growth.
authors.affiliation: Brain Research Unit, O.V. Lounasmaa Laboratory, Aalto Neuroimaging, Aalto University, Espoo, Finland; Outpatient Clinic of Child Phoniatrics, City of Helsinki, Helsinki, Finland. Electronic address: paivi@neuro.hut.fi.
authors.forename: Päivi
authors.initials: P
authors.lastname: Helenius
authors.affiliation: Brain Research Unit, O.V. Lounasmaa Laboratory, Aalto Neuroimaging, Aalto University, Espoo, Finland.
authors.forename: Päivi
authors.initials: P
authors.lastname: Sivonen
authors.affiliation: Brain Research Unit, O.V. Lounasmaa Laboratory, Aalto Neuroimaging, Aalto University, Espoo, Finland; Department of Psychology, University of Jyväskylä, Jyväskylä, Finland.
authors.forename: Tiina
authors.initials: T
authors.lastname: Parviainen
authors.affiliation: Network of Academic Health Centres, Departments of General Practice and Primary Healthcare, HUS Institute of Clinical Medicine, Helsinki, Finland; Primary Health Care Organization, City of Vantaa, Vantaa, Finland.
authors.forename: Pia
authors.initials: P
authors.lastname: Isoaho
authors.affiliation: Network of Academic Health Centres, Departments of General Practice and Primary Healthcare, HUS Institute of Clinical Medicine, Helsinki, Finland; Primary Health Care Organization, City of Vantaa, Vantaa, Finland.
authors.forename: Sinikka
authors.initials: S
authors.lastname: Hannus
authors.affiliation: Network of Academic Health Centres, Departments of General Practice and Primary Healthcare, HUS Institute of Clinical Medicine, Helsinki, Finland.
authors.forename: Timo
authors.initials: T
authors.lastname: Kauppila
authors.affiliation: Brain Research Unit, O.V. Lounasmaa Laboratory, Aalto Neuroimaging, Aalto University, Espoo, Finland.
authors.forename: Riitta
authors.initials: R
authors.lastname: Salmelin
authors.affiliation: Network of Academic Health Centres, Departments of General Practice and Primary Healthcare, HUS Institute of Clinical Medicine, Helsinki, Finland.
authors.forename: Leena
authors.initials: L
authors.lastname: Isotalo
mesh_terms: D000704:Analysis of Variance; D001303:Auditory Cortex / Q000254:growth & development / Q000503:physiopathology; D001931:Brain Mapping; D002648:Child; D005072:Evoked Potentials, Auditory; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007804:Language Development; D007806:Language Disorders / Q000175:diagnosis* / Q000503:physiopathology*; D007807:Language Tests; D015225:Magnetoencephalography; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013067:Speech Perception / Q000502:physiology; D013702:Temporal Lobe / Q000254:growth & development / Q000503:physiopathology*; D014825:Vocabulary
keywords: Auditory responses; Children; Cognitive neuroscience; Development; Functional imaging; MEG; N400m; Specific language impairment; Speech perception; Temporal cortex