Citation

Barchiesi G, Cattaneo L. Soc. Cogn. Affect. Neurosci. 2013; 8(6): 711-719.

Affiliation

Center for Mind / Brain Sciences ( CIMeC ), University of Trento Via delle Regole, 101. I - 38123 Mattarello (TN) - Italy Tel: + 39 0461/882743 Fax +39 0461/883066 luigi.cattaneo@unitn.it.

Copyright

(Copyright © 2013, Oxford University Press)

DOI

10.1093/scan/nss049

PMID

22563004

Abstract

Is a short visuo-motor associative training sufficient to reverse the visuo-motor tuning of mirror neurons in adult humans? We tested the effects of associative training on cortico-spinal modulation during action observation in the 100-320 ms interval after action onset. In two separate experiments, the acceleration of transcranial magnetic stimulation (TMS)-induced movements was recorded before and after training participants to respond to observed acts with an opposite or similar behavior. Before training, TMS-induced accelerations mirrored the observed action at 250 ms and 320 ms. After training, responses at 250 ms were unchanged and still mirrored the stimuli, without any effect of training direction. Only at 320 ms we observed training-dependent changes in evoked responses. A control experiment with non-biological rotational movements as visual stimuli indicated that spatial stimulus-response compatibility is not sufficient to account for the results of the two main experiments. We show that the effects of a short visuo-motor associative training are not pervasive on the automatic mirror responses. 'Early' (250 ms) responses were not influenced by training. Conversely only 'late' (320 ms) responses changed according to the training direction. This biphasic time-course indicates that two distinct mechanisms produce the automatic mirror responses and the newly learned visuo-motor associations.

Language: en