Neurophysiological Mechanisms
A large number of functional neuroimaging studies have demonstrated that motor imagery is associated with the specific activation of the neural circuits involved in the early stage of motor control (i.e., motor programming). This circuits includes the supplementary motor area, the primary motor cortex, the inferior parietal cortex, the basal ganglia, and the cerebellum. Such physiological data gives strong support about common neural mechanisms of imagery and motor preparation.
Measurements of cardiac and respiratory activity during motor imagery and during actual motor performance revealed a covariation of heart rate and pulmonary ventilation with the degree of imagined effort. Motor imagery activates motor pathways. Muscular activity often increases with respect to rest, during motor imagery. When this is the case, EMG activity is limited to those muscles that participate in the simulated action and tends to be proportional to the amount of imagined effort.
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