The representing brain: Neural correlates of motor intention and imagery

Abstract

This paper concerns how motor actions are neurally represented and coded. Action planning and motor preparation can be studied using a specific type of representational activity, motor imagery. A close functional equivalence between motor imagery and motor preparation is suggested by the positive effects of imagining movements on motor learning, the similarity between the neural structures involved, and the similar physiological correlates observed in both imaging and preparing. The content of motor representations can be inferred from motor images at a macroscopic level, based on global aspects of the action (the duration and amount of effort involved) and the motor rules and constraints which predict the spatial path and kinematics of movements. A more microscopic neural account calls for a representation of object-oriented action. Object attributes are processed in different neural pathways depending on the kind of task the subject is performing. During object-oriented action, a pragmatic representation is activated in which object affordances are transformed into specific motor schemas (independently of other tasks such as object recognition). Animal as.svell as human clinical data implicate the posterior parietal and premotor cortical areas in schema instantiation. A mechanism is proposed that is able to encode the desired goal of the action and is applicable to different levels of representational organization.

Motor learning enhances perceptual judgment: a case for action-perception transfer

“…More recently, Vogt (1995) found that the temporal consistency in producing sequential arm movements improved to the same extent through mental, observational, and physical practice. Whereas the equivalence of motor imagery and physical practice could be expected from earlier behavioral and neurophysiological work (see Jeannerod, 1994Jeannerod, , 1997Jeannerod & Decety, 1995), the equivalence of observational and physical practice was unexpected. It indicates that motor structures are already involved during movement observation and thus provides a theoretical alternative to distinct stage models.…”

“…In both of these cases of intermodal matching, however, sensory inputs from two modalities were present at some point, whereas in our visual test, participants would have had to generate expected kinesthetic signals from the visual input. Such visually induced kinesthetic images are certainly conceivable (Jeannerod, 1994(Jeannerod, , 1997. Our main discomfort with this explanation for APT is, however, that we would be left with a number of arguments for the involvement of visuomotor couplings in the visual task (see Introduction and Discussion of Experiment 1), but these couplings would not serve any function.…”

“…To further investigate the role of kinesthetic feedback during motor practice, one could reduce motor practice to its preparatory component using motor imagery instructions (Jeannerod, 1994(Jeannerod, , 1997. This option was not available for the current task, where motor practice involved experimenter-supplied feedback on performance.…”

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

“…It is assumed that motor imagery is an internal simulation of the overt movement program (Jeannerod, 1994;Jeannerod and Frak, 1999). Thus, the essential process to perform motor imagery is the programming and planning of the movement in premotor cortices.…”

“…the mental simulation of a motor act. It has been suggested that kinesthetic motor imagery involves the same neural network as motor planning (Jeannerod, 1994;Jeannerod and Frak, 1999), which in turn is thought to rely on the same motor structures as motor execution (Johnson-Frey, 2004;Munzert et al, 2009;Sharma et al, 2006). In support of this view, motor imagery shares a number of similarities with overt movement execution, such as behavioral (Decety and Jeannerod, 1995) and physiological parameters (Kranczioch et al, 2008(Kranczioch et al, , 2009, and, importantly, the functional neuroanatomical correlates (Decety, 1996;Lotze and Halsband, 2006;Porro et al, 1996;Szameitat et al, 2007aSzameitat et al, , 2007b.…”