title: Sensorimotor semantics on the spot: brain activity dissociates between conceptual categories within 150 ms.
abstract: Although semantic processing has traditionally been associated with brain responses maximal at 350-400 ms, recent studies reported that words of different semantic types elicit topographically distinct brain responses substantially earlier, at 100-200 ms. These earlier responses have, however, been achieved using insufficiently precise source localisation techniques, therefore casting doubt on reported differences in brain generators. Here, we used high-density MEG-EEG recordings in combination with individual MRI images and state-of-the-art source reconstruction techniques to compare localised early activations elicited by words from different semantic categories in different cortical areas. Reliable neurophysiological word-category dissociations emerged bilaterally at ~ 150 ms, at which point action-related words most strongly activated frontocentral motor areas and visual object-words occipitotemporal cortex. These data now show that different cortical areas are activated rapidly by words with different meanings and that aspects of their category-specific semantics is reflected by dissociating neurophysiological sources in motor and visual brain systems.
authors.affiliation: MRC Cognition and Brain Sciences Unit, Cambridge, UK. rachel.moseley@mrc-cbu.cam.ac.uk
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Moseley
authors.forename: Friedemann
authors.initials: F
authors.lastname: Pulvermüller
authors.forename: Yury
authors.initials: Y
authors.lastname: Shtyrov
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D003210:Concept Formation; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D015225:Magnetoencephalography; D008297:Male; D010775:Photic Stimulation; D012660:Semantics