Brain Activity during the Observation, Imagery, and Execution of Tool Use: An fNIRS/EEG Study

Studies have shown that improvements in the upper limb function of post-stroke victims tend to be worse than those in the lower limb functions, and there is generally a poorer prognosis for the upper limbs [1]. This is because the upper limbs demand greater involvement of the parietal lobe (surrounding the intraparietal sulcus and the inferior parietal lobule) and the frontal lobe (ventral premotor area) compared with the lower limbs, in addition to requiring a more advanced information processing [2]. Furthermore, when hemiplegia is seen in a stroke victim, the individual is no longer capable of motor function. This causes greater difficulties in the functional activation of these brain regions.