ABSTRACT
Axons from the cells cross over to the other side and ascend to the thalamus. There they synapse with neurons whose axons pass to the somatosensory cortex, located in the postcentral gyrus. They showed that the regions of the body are represented in the somatosensory cortex in a systematic way. More sensitive parts of the body occupy a larger area of the cortex. Vision and audition are exteroceptive senses, giving us information about the external environment. They are also distance senses, in that they respond to stimuli and events not in contact with our bodies. There are several skin senses, or senses of touch. The receptors for pain are free nerve endings distributed throughout the skin as well as in muscles, joints and internal organs. These are called nociceptors. Pain information is known to be passed from the thalamus to the cingulate cortex, which is part of the limbic system.
