Motor system iii posterior parietal cortex: the posterior parietal cortex (ppc) determines eye-centered locations and plans movement. The receptive field of visual cortex neurons (occipital lobe) is retinocentric. Ppc neurons receive eye/head position and image location information and encode them as the gain of discharge rate and receptive field, respectively; this is all the information needed to for. In a delay task, ppc neurons encode target of intended movement during delay period even if the target disappears. Ppc does not encode forces needed to move to the target. The ppc also computes hand position from visual and/or proprioception input; the visual sight of one"s own hand is particularly meaningful, as there are ppc cells that only respond to the image of the hand in certain positions. Premotor cortex subtracts hand position from target position to determine displacement vector for hand and decides whether or not to execute the movement.