Ipsilateral involvement of primary motor cortex during motor imagery

Abstract

To investigate whether motor imagery involves ipsilateral cortical regions, we studied haemodynamic changes in portions of the motor cortex of 14 right-handed volunteers during actual motor performance (MP) and kinesthetic motor imagery (MI) of simple sequences of unilateral left or right finger movements, using functional magnetic resonance imaging (fMRI). Increases in mean normalized fMRI signal intensities over values obtained during the control (visual imagery) task were found during both MP and MI in the posterior part of the precentral gyrus and supplementary motor area, both on the contralateral and ipsilateral hemispheres. In the left lateral premotor cortex, fMRI signals were increased during imagery of either left or right finger movements. Ipsilateral cortical clusters displaying fMRI signal changes during both MP and MI were identified by correlation analyses in 10 out of 14 subjects; their extent was larger in the left hemisphere. A larger cortical population involved during both contralateral MP and MI was found in all subjects. The overall spatial extent of both the contralateral and the ipsilateral MP + MI clusters was approximately 90% of the whole cortical volume activated during MP. These results suggest that overlapping neural networks in motor and premotor cortex of the contralateral and ipsilateral hemispheres are involved during imagery and execution of simple motor tasks.

Differential Contribution of Bilateral Supplementary Motor Area to the Effective Connectivity Networks Induced by Task Conditions Using Dynamic Causal Modeling

“…This resulted in the suppressive role of contralateral SMA to contralateral M1. Some earlier studies had reported that the strong activity in M1 during motor execution was significantly suppressed during motor imagery (Lotze et al, 1999;Porro et al, 1996Porro et al, , 2000. Our results demonstrated that the decreased activity in M1 was induced by the suppressive function of task input through contralateral SMA.…”

“What” Becoming “Where”: Functional Magnetic Resonance Imaging Evidence for Pragmatic Relevance Driving Premotor Cortex

“…One might argue that this activation pattern resulted from a not instructed overt or covert (imagined) coproduction of the attended stimulus sequence. It has been demonstrated that execution as well as imagery (although to a lesser extent) of finger movements involve contralateral sensorimotor areas (Porro et al, 1996(Porro et al, , 2000Grafton et al, 1998;Ehrsson et al, 2003;Nair et al, 2003). It is typically reported that either both primary motor and premotor areas (Porro et al, 1996;Lotze et al, 1999;Boecker et al, 2002;Stippich et al, 2002;Ehrsson et al, 2003) or premotor areas alone (Decety et al, 1994;Stephan et al, 1995;Deiber et al, 1998;Dechent et al, 2004) are engaged during motor imagery.…”

Cortical lateralization in stroke patients measured by event-related potentials during motor imagery

“…It is a complex cognitive process that is involved in the reactivation of specific motor actions within working memory (9,10). Neuroimaging studies have shown that MI activates more or less the same brain regions as the actual execution of a movement, including motor and premotor areas, the prefrontal cortex and the parietal cortex (10)(11)(12)(13)(14)(15). Studies have demonstrated the benefits of MI in improving motor performance in patients with neurological diseases (16).…”