He is known as the homunculus or “little man”.
He may look odd but he is a “… visualisation of the relationship between the human body parts and the area of brain responsible for them.
The homunculus comes in two varieties – sensory and motor. The sensory homunculus shows how much brain power is dedicated to sensing different body parts. It looks weird because the relative proportions of the body parts are not about physical size, but the number of related neural connections in the brain. The motor homunculus depicts the size of body parts based on the complexity of movements they can perform. When you think about how complex our hand and facial movements are, you can see why they’re so big on the homunculus.” Follow this link to see a short video explaining this principle. ABC iView – Catalyst, 11/8/2011. http://www.abc.net.au/catalyst/stories/3291550.htm
How does this relate to YOGA? During the guided relaxation practice of Yoga Nidra the awareness is rotated around the various body parts with added emphasis on the fingers, hands, eyes, lips, nose because these body parts occupy a large proportion in the brain and motor cortex. In fact these corresponding areas are almost as large as the space allotted to the entire remainder of the body.
That is why in Yoga Nidra there is a precise order for the rotation of consciousness throughout the body since it induces “…a flow of pranic energy within the neural circuit of the motor homunculus. This flow is accompanied by a subjective experience of relaxation, release or “letting go”, as a spontaneous dissociation of consciousness from the sensory and motor channels of experience occurs.” (see reference below). This then leads to pratyahara or sense withdrawal which is the 5th stage of Patanjali’s Raja Yoga.
Yoga Nidra, Swami Satyananda Saraswati . Yoga Publications Trust, Munger, Bihar India.