Linguistics Research Today is a free monthly online journal that collates and summarizes the latest research about Linguistics, including details on human language, phonetics, syntax, phonology.

Differential activation of frontal lobe areas by lexical and semantic language tasks: a functional magnetic resonance imaging study.

Blacker D, Byrnes ML, Mastaglia FL, Thickbroom GW

Brain Research Laboratory, Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands, WA 6009, Australia.

To determine whether frontal lobe regions, including Broca's area, dorsolateral prefrontal cortex (DLPFC) and supplementary motor area (SMA), are differentially activated during lexical and semantic language tasks, we used functional magnetic resonance imaging in eight healthy right-handed subjects silently performing two semantic tasks (adjective and verb generation) and a lexical retrieval task (noun recall). Activation was observed in Broca's area, DLPFC and SMA for all tasks. Broca's area activation was approximately doubled during the semantic tasks compared with the lexical task (verbs vs nouns: 19.1+/-4.5 vs 8.9+/-1.6 voxels, p=0.02; adjectives vs nouns 24.4+/-7.5 vs 10.1+/-2.8 voxels, p=0.04); however, there were no significant differences in the DLFPC or SMA across tasks. We conclude that Broca's area is more active during tasks that have a semantic content, whereas areas involved in preparatory processing (SMA) and memory retrieval (DLPFC) are engaged equally during both types of task.

Published 13 January 2006 in J Clin Neurosci, 13(1): 91-5.
Full-text of this article is available online (may require subscription).

© 2005-2008 Linguistics Research Today. All Rights Reserved.