The sensory homunculus is a physical representation of the somatosensory cortex. The word homunculus comes from the latin word “little man” and in psychology is referred to as the “little man inside your brain”. A homunculus has oversized lips, hands, feet, and tongue with skinny arms and legs. The somatosensory cortex is found within the parietal lobe behind the frontal cortex where it processes touch sensory information. The homunculus’ body is scaled according to the amount of cortex it is devoted to it. For example, the homunculus’ large hands represents an extensive proportion of touch receptors within the somatosensory cortex, meaning our hands are a lot more sensitive to touch than the rest of the body. Each body part’s location on the somatosensory cortex can also be topographically projected as seen in the top left image above.

Dr. Wilder Graves Penfield, an established neurosurgeon, was the first to map out the brain’s sensory and motor cortices through neural stimulation. The idea for mapping the cortex was first discovered during his treatment of epilepsy patients, where he used electrical probes on conscious patients to pinpoint and remove seizure causing nerve cells in the brain. He was inducted into the Canadian Medical Hall of Fame in 1994 for his achievements.

Show us a drawing of your homunculus and post it in the comments below!

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