If words are frequently used while actions are being performed, the neurons controlling the actions should frequently fire together with the neurons involved in language processing. Hebbian correlation learning predicts that action- and language-related neurons in motor/premotor cortex and in perisylvian language cortex become mutually linked. This implies different cortical distributions of the cell assemblies that represent and process words such as lick, pick and kick that "mean" face-, arm- and leg-actions, respectively (Somatotopy-Of-Action-Words (SAW) Model, 1-3). Experiments using spoken and written words from 3 languages (English, Finnish, German) carried out with four neuroimaging methods (fMRI, EEG, MEG, TMS) and implementing three different tasks (lexical decision, silent reading, watching video while ignoring words) indicated that three semantic subtypes of action words (face-, arm- and leg-words) are related to different areas in the fronto-central cortex. The results support the SAW Model (1-3) and demonstrate that semantic processes occur early (~200ms).
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