Distinct processing of function verb categories in the human brain

Abstract

A subset of German function verbs can be used either in a full, concrete, heavy ( take a computer ) or in a more metaphorical, abstract or light meaning ( take a shower , no actual taking involved). The present magnetencephalographic (MEG) study explored whether this subset of light verbs is represented in distinct cortical processes. A random sequence of German heavy , light , and pseudo verbs was visually presented in three runs to 22 native German speakers, who performed lexical decision task on real versus pseudo verbs. Across runs, verbs were presented (a) in isolation, (b) in minimal context of a personal pronoun, and (c) light verbs only in a disambiguating context sentence. Central posterior activity 95 135 ms after stimulus onset was more pronounced for heavy than for light uses, whether presented in isolation or in minimal context. Minimal context produced a similar heavyNlight differentiation in the left visual word form area at 160 200 ms. Light verbs presented in sentence context allowing only for a heavy reading evoked larger lefttemporal activation around 270 340 ms than the corresponding light reading . Across runs, real verbs provoked more pronounced activation than pseudo verbs in left-occipital regions at 110 150 ms. Thus, heavy versus light readings of verbs already modulate early posterior visual evoked response even when verbs are presented in isolation. This response becomes clearer in the disambiguating contextual condition. This type of study shows for the first time that language processing is sensitive to representational differences between two readings of one and the same verb stem.