Neural substrates for observing and imagining non-object-directed actions

Abstract

The present fMRI study was aimed at assessing the cortical areas active when individuals observe non-object-directed actions (mimed, symbolic, and meaningless), and when they imagine performing those same actions. fMRI signal increases in common between action observation and motor imagery were found in the premotor cortex and in a large region of the inferior parietal lobule. While the premotor cortex activation overlapped that previously found during the observation and imagination of object-directed actions, in the parietal lobe the signal increase was not restricted to the intraparietal sulcus region, known to be active during the observation and imagination of object-directed actions, but extended into the supramarginal and angular gyri. When contrasting motor imagery with the observation of non-object-directed actions, signal increases were found in the mesial frontal and cingulate cortices, the supramarginal gyrus, and the inferior frontal gyrus. The opposite contrast showed activation virtually limited to visual areas. In conclusion, the present data define the common circuit for observing and imagining non-object-directed actions. In addition, they show that the representation of non-object-directed actions include parietal regions not found to be involved in coding object-directed actions.

The functional role of the parieto-frontal mirror circuit: interpretations and misinterpretations

“…unlike in monkeys, the parieto-frontal mirror circuit of humans also becomes active during the observation of individual movements [55][56] . The initial evidence for this mechanism was based on TMS experiments which indicated that the observation of the movements of others results in an activation of the muscles involved in the execution of those movements [32][33][34][35][36] .…”

Does It Look Painful or Disgusting? Ask Your Parietal and Cingulate Cortex

“…First, avoidance behavior is likely to be triggered by disgusting stimuli, too. Second, the pattern of parietal activation does not seem to be specific to upper arm movement planning or imagery (Ruby and Decety, 2003;Lui et al, 2008a). Third, they are not accompanied by a specific premotor/posterior parietal cortex activation.…”

Cortical activation during executed, imagined, observed, and passive wrist movements in healthy volunteers and stroke patients

“…However, the majority of this literature investigated only one mode of covert movement mode or, at most, compared two modes, usually motor imagery and observation (Clark et al, 2003;Filimon et al, 2007;Iseki et al, 2008;Lui et al, 2008;Macuga and Frey, 2012;Munzert et al, 2008;Piefke et al, 2009;Roosink and Zijdewind, 2010;Wang et al, 2008). Therefore inferences between studies have to be made when comparison between all modes of covert movement is to be conducted.…”