Where Are Genitals Represented in the Brain?

Paracelsus claimed in the 16th century that he knew how to create a small man by placing human semen in a sealed container. The recipe for turning base metals into gold was more useful than the ones for turning it into gold, but the term has survived through the centuries, making its way into literature, television and even video games. Neuroscience textbooks succeeded better than any other medium in defining the contemporary meaning of homunculus, despite stiff competition from popular culture.

The depiction of a homunculus that wrapped around the somatosensory cortex was published in 1950 by a neurosurgeon and a colleague. The position of the head, shoulders, knees, and toes in the cortex were laid out somatotopically, meaning they were presented in the same order in the brain as they appear on the body. The ridge at the top of the brain where touch information is processed is located at the very outside edge of the postcentral gyrus. The midline is where the two hemispheres of the brain meet. Sensory information from the left side of the body is processed in the right hemisphere. The penis was hidden underneath the toes on the inside wall of the gyrus. The homunculus in this first rendition of a neural touch map was not a good representation of what sex is like.