Contrasting effects of vocabulary knowledge on temporal and parietal brain structure across lifespan.
Using behavioral, structural, and functional imaging techniques, we demonstrate contrasting effects of vocabulary knowledge on temporal and parietal brain structure in 47 healthy volunteers who ranged in age from 7 to 73 years. In the left posterior supramarginal gyrus, vocabulary knowledge was positively correlated with gray matter density in teenagers but not adults. This region was not activated during auditory or visual sentence processing, and activation was unrelated to vocabulary skills. Its gray matter density may reflect the use of an explicit learning strategy that links new words to lexical or conceptual equivalents, as used in formal education and second language acquisition. By contrast, in left posterior temporal regions, gray matter as well as auditory and visual sentence activation correlated with vocabulary knowledge throughout lifespan. We propose that these effects reflect the acquisition of vocabulary through context, when new words are learnt within the context of semantically and syntactically related words.
Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London WC1N 3BG, UK. fiona.richardson@ucl.ac.uk
Fiona M
FM
Richardson
Michael S C
MS
Thomas
Roberto
R
Filippi
Helen
H
Harth
Cathy J
CJ
Price
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001931:Brain Mapping; D002648:Child; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007804:Language Development; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D010296:Parietal Lobe / Q000502:physiology* / Q000503:physiopathology; D010364:Pattern Recognition, Visual; D010775:Photic Stimulation / Q000379:methods; D011594:Psychometrics / Q000379:methods; D011930:Reaction Time; D012660:Semantics; D013702:Temporal Lobe / Q000098:blood supply / Q000502:physiology*; D014825:Vocabulary; D055815:Young Adult
D010100:Oxygen