Authors:

SHTYROV, Y. & PULVERMULLER, F.

Reference:

Year of publication:

2003

CBU number:

5741

Abstract:

Mismatch negativity (MMN), an index of experience-dependent memory traces, was used to investigate the processing of action-related words in the human brain. Responses to auditory presented movement-related English words were recorded in non-attend odd-ball paradigm using a high-density EEG set-up. MMN was calculated using responses to the same words presented as standard and deviant stimuli in different sessions to avoid contamination from phonetic-acoustic differences. The topography of the mismatch negativity to action words showed unusual centro-posterior distribution of the responses suggesting that activity was at least in part generated posterior to usually observed frontal MMNs. Moreover, responses to hand-related word stimulus ([pick]) had a more spread-out lateral distribution, whereas leg-related stimulus ([kick]) elicited a more focal dorsal negativity. These differences, remarkably reminiscent of sensorimotor cortex topography, were confirmed by source analysis (minimum-norm current estimates), which also suggested differentially distributed activation for the two stimuli. We suggest that these results indicate activation of distributed neuronal assemblies which function as category-specific memory traces for words and may involve sensorimotor cortical structures for encoding action words.