Atypical right hemisphere specialization for object representations in an adolescent with specific language impairment.

TitleAtypical right hemisphere specialization for object representations in an adolescent with specific language impairment.
Publication TypeJournal Article
Year of Publication2014
AuthorsBrown TT, Erhart M, Avesar D, Dale AM, Halgren E, Evans JL
JournalFront Hum Neurosci
Date Published2014

Individuals with a diagnosis of specific language impairment (SLI) show abnormal spoken language occurring alongside normal non-verbal abilities. Behaviorally, people with SLI exhibit diverse profiles of impairment involving phonological, grammatical, syntactic, and semantic aspects of language. In this study, we used a multimodal neuroimaging technique called anatomically constrained magnetoencephalography (aMEG) to measure the dynamic functional brain organization of an adolescent with SLI. Using single-subject statistical maps of cortical activity, we compared this patient to a sibling and to a cohort of typically developing subjects during the performance of tasks designed to evoke semantic representations of concrete objects. Localized patterns of brain activity within the language impaired patient showed marked differences from the typical functional organization, with significant engagement of right hemisphere heteromodal cortical regions generally homotopic to the left hemisphere areas that usually show the greatest activity for such tasks. Functional neuroanatomical differences were evident at early sensoriperceptual processing stages and continued through later cognitive stages, observed specifically at latencies typically associated with semantic encoding operations. Our findings show with real-time temporal specificity evidence for an atypical right hemisphere specialization for the representation of concrete entities, independent of verbal motor demands. More broadly, our results demonstrate the feasibility and potential utility of using aMEG to characterize individual patient differences in the dynamic functional organization of the brain.

Alternate JournalFront Hum Neurosci
PubMed ID24592231
PubMed Central IDPMC3924145
Grant ListP50 NS022343 / NS / NINDS NIH HHS / United States
R01 DC005650 / DC / NIDCD NIH HHS / United States
IRG Funded