Fish Fertilize Trees
By Maya C. Lemaire
2018
2018
Foot Fetishes and Phantom Limbs
Foot fetish. These controversial words instill a myriad of different emotions from person to person and love them or hate them, there are people out there that have gone to prison for their obsessions.
Michael Wyatt, the “Toe Suck Fairy”, was arrested in 2012 and served time for a year for a series of assaults directed at women’s feet – now you may be wondering, what could possibly be so fascinating about feet that it drives someone to such extreme actions?
Neuroscientist Vilanayar S. Ramachandran[1] approached the mystery of foot fetishes while studying phantom limb syndrome (the sensation that an amputated or missing limb is still attached) and discovered that podophilia (attraction to feet), may stem from a “neural crosstalk” between feet and genitals, as they occupy adjacent areas in the somatosensory homunculus.
As shown in the diagram[2] (mapped out by Wilder Penfield), the feet are positioned right next to the genitals and due to a phenomenon called “spreading activation”[3], when the “foot” part of the brain is activated, the genital area may also be linked - therefore, sexual stimulation is then associated with the feet.
However other studies argue that the foot is not a source of somatic pleasure, but a visual pleasure and is therefore based on some form of a neural body map elsewhere in the brain, just not the S1.
So how is this related to phantom limbs?
In a horrific study conducted by Dr. Tim Pons, he severed the nerve endings of a monkey’s arm (leaving it paralyzed) and discovered that upon stimulating the somatosensory cortex associated with the face, the cells associated with the hand also fired.
Inspired by this, Ramachandran conducted his own experiment and found that stroking different parts of the face led to perceptions of being touched on different parts of the phantom limb for some amputees.[4] This is where his theories on the “neural crosstalk” of feet and genitals come in.
He hypothesized that once the somatosensory cortex learns that a limb no longer works, the neurons correlating with that limb start to invade neighbouring areas[5] (therefore foot and genital overlap is possible).
People began to come forward with confessions of feeling strange sensations in their phantom limbs and a few select conversations with an amputee working at Beth Israel Hospital and an engineer that had lost their leg below the knee appeared to support Ramachandran’s theory.
"Well, I feel a little embarrassed to tell you this . . . Doctor, every time I have sexual intercourse, I experience sensations in my phantom foot . . . I actually experience my orgasm in my foot. And therefore it's much bigger than it used to be because it's no longer confined to just my genitals."
In his acclaimed book “Phantoms in the Brain”, Ramachandran theorized that there was a link between the phenomenon of phantom limbs and neural plasticity (the ability of the brain to change throughout an individual's life) in the adult human brain. He showed that there indeed were changes in the somatosensory cortex of several amputees and that after the loss of the limb, sensory inputs no longer correlated to the exact same spot as before.
What does this mean?
There is still no official consensus on the cause of phantom limb pain and his theory on cortical reorganization, but if Ramachandran’s theories are indeed true, this could revolutionize how phantom limb pain is treated (as currently, there is still no concrete “cure” for it). Furthermore, solutions to many other life-threatening medical conditions such as stroke, cerebral palsy and traumatic brain injuries could be better developed with more research into cortical remapping and CIMT (constraint-induced movement therapy) already begins to utilize this.
[1] https://fr.wikipedia.org/wiki/Vilayanur_S._Ramachandran
[2] http://blogs.discovermagazine.com/neuroskeptic/files/2013/09/homonc.png
[3] https://brainspiner.wordpress.com/2010/07/15/in-your-brain-feet-and-sex-are-old-friends/
[4] https://en.wikipedia.org/wiki/Phantom_limb
[5] https://scienceblogs.com/neurontic/2006/04/01/penfields-homunculus-and-the-m
Sources:
Google. 2019. Somatosensory homunculus. [Online] [Accessed January 2019] Available from: https://www.google.com/search?q=somatosensory+homunculus&safe=active&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiPhLyJ5vjfAhUBa94KHYEHAaEQ_AUIDigB&biw=1280&bih=596#imgrc=COYw6qY_dAXrNM:
Further reading:
http://turnbull-lab.bangor.ac.uk/documents/TurnbullErogenousCortex2013.pdf
https://en.wikipedia.org/wiki/V._S._Ramachandran#cite_note-21
https://studyres.com/doc/8054732/brain-maps-%E2%80%93-the-sensory-homunculus
Jing-Wen Weng
Year 12 student at Bangkok Patana School