Is reaching eye-centered, body-centered, hand-centered, or a combination?
There are currently three main views on the neural basis of visually guided reaching: 1) neurons in the superior parietal lobe guide arm movements in a spatial framework that is centered on the body; 2) neurons in the intraparietal sulcus guide arm movements in a spatial framework that is centered on the eye; 3) neurons in the caudal part of premotor cortex guide arm movements in a spatial framework that is centered on the arm and hand. The three viewpoints are mutually compatible and may fit into a larger pattern. Eye-centered representations of target position, and body-centered representations of arm and hand position, may be integrated to form a hand-centered representation close to the output stage in caudal premotor and primary motor cortex.
Reviews in the Neurosciences