title: Object activation from features in the semantic system.
abstract: The human brain is thought to elicit an object representation via co-activation of neural regions that encode various object features. The cortical regions and mechanisms involved in this process have never been elucidated for the semantic system. We used functional magnetic resonance imaging (fMRI) to evaluate regions activated during a task designed to elicit object activation within the semantic system (e.g., presenting the words "desert" and "humps" with the task to determine if they combine to form an object, in this case a "camel"). There were signal changes in the thalamus for word pairs that activated an object, but not for pairs that (a) failed to activate an object, (b) were simply semantically associated, or (c) were members of the same category. These results suggest that the thalamus has a critical role in coordinating the cortical activity required for activating an object concept in the semantic system.
authors.affiliation: Division of Neuroradiology, John Hopkins Hospital, Johns Hopkins University, Baltimore, MD 21287, USA. mkraut@rad.jhu.edu
authors.forename: Michael A
authors.initials: MA
authors.lastname: Kraut
authors.forename: Sarah
authors.initials: S
authors.lastname: Kremen
authors.forename: Jessica B
authors.initials: JB
authors.lastname: Segal
authors.forename: Vincent
authors.initials: V
authors.lastname: Calhoun
authors.forename: Lauren R
authors.initials: LR
authors.lastname: Moo
authors.forename: John
authors.initials: J
authors.lastname: Hart
mesh_terms: D000328:Adult; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D012660:Semantics; D013788:Thalamus / Q000502:physiology*; D014936:Word Association Tests