PT  - JOURNAL ARTICLE
AU  - Rogier B. Mars
AU  - Miriam C. Klein
AU  - Franz-Xaver Neubert
AU  - Etienne Olivier
AU  - Ethan R. Buch
AU  - Erie D. Boorman
AU  - Matthew F. S. Rushworth
TI  - Short-Latency Influence of Medial Frontal Cortex on Primary Motor Cortex during Action Selection under Conflict
AID  - 10.1523/JNEUROSCI.1396-09.2009
DP  - 2009 May 27
TA  - The Journal of Neuroscience
PG  - 6926--6931
VI  - 29
IP  - 21
4099  - http://www.jneurosci.org/content/29/21/6926.short
4100  - http://www.jneurosci.org/content/29/21/6926.full
SO  - J. Neurosci.2009 May 27; 29
AB  - Medial frontal cortex (MFC) is crucial when actions have to be inhibited, reprogrammed, or selected under conflict, but the precise mechanism by which it operates is unclear. Importantly, how and when the MFC influences the primary motor cortex (M1) during action selection is unknown. Using paired-pulse transcranial magnetic stimulation, we investigated functional connectivity between the presupplementary motor area (pre-SMA) part of MFC and M1. We found that functional connectivity increased in a manner dependent on cognitive context: pre-SMA facilitated the motor evoked-potential elicited by M1 stimulation only during action reprogramming, but not when otherwise identical actions were made in the absence of conflict. The effect was anatomically specific to pre-SMA; it was not seen when adjacent brain regions were stimulated. We discuss implications for the anatomical pathways mediating the observed effects.