Homunculous was the invention of Neuroscientist Wilder Penfield

He worked with patients by inserting extremely thin electrodes stimulating each area of the brain precisely the patient would verify where on the body they felt sensations which became the first topographical mapping of the body in the brain there were two maps that virtually identical (somatosensory Homunculous which is what we use to represent the feedback of the body to the brain and motor Homunculous which represents the movement in the body from efferent signals

The gist though is the fact that the size of the representation in the brain does not match the anatomical size

Penfield tells us the neural real estate that the maps represent relate to function sensation variation in movement and volume of movement so each map is an individual map based on the person and how they behave and interact with the environment

For example a golfer who has learned thru touch has a larger map of the hand than a golfer who developed a swing by other means it is unique and constantly changing according to practice