The somatosensory system

A hierarchical system through the somatosensory cortex builds representations of touch and of the positions of the limbs in space up through parietal cortex areas 5 and 7b, where the system is interfaced to the visual system for the computations involved in reaching into space and grasping objects. Attractor network mechanisms for decision-making between somatosensory stimuli are described. In the orbitofrontal cortex, the affective value of pleasant touch and of pain is represented.