Wednesday, May 25, 2011

Homunculus of Touch

Argh. Been feeling kind of defeated lately with these frustrating qbank questions. Overall I'm improving somewhat, but my scores are erratic - they spike up and then plummet and then spike again. Anyway, after studying neurology for the better part of a day, I managed to pull off a 71% on a block of neuro questions! Not sure how that happened, as I generally consider neuro to be one of my weaker areas.

Somewhat related, one of the most interesting things I remembered learning while going through neuro was the somatosensory homunculus. You see, sensation is unevenly distributed throughout our bodies and our brains form a somatosensory homunculus of it on the pre-frontal cortex. It's rather interesting. So think, what are the most sensitive parts of your body? Now look at the distribution of the somatosensory cortex:

Does it match what you thought? You'll notice that the face and hands are far over-represented. The fingers, lips, and face are more sensitive than pretty much any other part of the body. Do you notice the genitals? Hint: it's by the feet. Interesting that it comprises such a small part of the homunculus. A drawing of the somatosensory homunculus would be like this:

So I find it kind of funny how we put so much focus and attention on the penis and genitals. Yeah, sure, it's pretty sensitive given its body surface area (more so than, say, the legs), but it pales in comparison to the hands, lips, and face. One would probably expected the homunculus to be more like this:

Lol, right? Well, apparently, some recent-ish studies kind of hint that the homunculus actually is a bit more like this last version (the things you find on Google, lol). In 2005, Kell et al. attempted to update the somatosensory homunculus for males - chiefly that genital sensation is not near the feet in the somatosensory cortex, but closer to where it'd be on the body. In 2007, Sorrells et al. reported that 5 of the most sensitive parts of the penis is removed during circumcision (so it's curious, and incorrect, that the homunculus above is circumcised).

Of course, one has to wonder, what about women? It's been presumed that the number of genital nerve endings in men and women are about equal; however, there just aren't that many such studies out there done on women. There are numbers floating around in the internet (with no source that I can pin down) stating that the glans clitoris (basically the entire clitoris) has about 8000 nerve endings, whereas the glans penis (head of the penis) has about 4000; presumably, the other 4000 nerve endings are distributed along the shaft. Furthermore, the foreskin has about 10,000 to 20,000 nerve endings (and the clitoral hood somewhere around there but perhaps a little less).

What does all this mean? Who knows. Everyone experiences sensation different anyhow. Sure, there are objective ways to test sensation: 2-point discrimination, temperature, fine touch, coarse touch, vibration, etc. And there are different nerves that sense different things (apparently the foreskin has a bunch of the kind that detect fine touch and vibration). But what it all "means" is another thing entirely. I mean, though the hands are sensitive, they're not particularly sensual, am I right?

Anywho, I'm rambling. I hope you were entertained and curiosity piqued. :-P

8 comments:

Biki said...

Cool post!

Yeah, I think it's rather interesting how little research has been done on womens genitalia. But then, to the vast majority of the medical community women on a whole are seen as smaller men.

I LOVED THE STATUES OF THE HOMUNCULUS! cool and yet somehow funny.

Ya know? I'm thinking you need to take a day off to let you brain rest and relax. Yes, yes I know you have well loads to stuff into your head, but i think it would help you to think/study if you took at least an afternoon off.

Good luck!

stentor said...

Spock, I can't feel anything.. anything at all.

Jim, when the shuttle passed through the denervian field,
a part of you became separated, something that appears to be
what is called a homunculus.

Then where is it now?

Somewhere on this ship.

cooolchix5 said...

agreed there def need to be mor studeez on women genital

Ethan Bradberry said...

So I tried to make a humonculus and one of these came out... idk what to do so I started feeding it small peices of steak but it regurgitated so I did grass instead. I made another one yet this one was female arm they started mating but the female ate the male afterwards. I tried to stop it but it but part of my finger off(only a small part) and it killed him so I just let it happen. I went to sleep and woke up, it was about 2 feet tall. I let it sleep In my bathroom and has started using broken English. I bought a cage and have let it been in there for a while now and it has stayed at about 2 feet tall.

Ethan Bradberry said...

Follow up. I realized it's full potential as a sex slave shortly afterwards I woke up to it preforming fellatio on me with its big lips I bought bondage and tied it up in the cage. It's been in there for about 2 days now.

Ethan Bradberry said...

Right after I posted this comment it started giving birth and died but I've continued to preform anal sex on it worried about doing the vigina. I have been trying to find a name for it so I just named it and every one of the babies(2) Heather Saxton.

Ethan Bradberry said...

There's one deformed baby that has been tunning into the wall and likes to watch animated porn. I think it's called "hentai" or something? I named this one Dane saxton. It has very small genitalia and like 25% of a vigina... very unique.

Ethan Bradberry said...

I've tried to preform normal sex through the vigina but it has teeth in it's vigina and cut it up like a meat grinder! Damn the tooth fairy came early because I pulled those out. Luckily it's still deceased. I tried to do anal after that to finish but keep in mind it's a two foot tall humonculus and it went into the stomache acid so now I call el pene darth Vader because it looks like Aniken Skywalker after he fell into the lava pit. I just circumcised myself so now it looks somewhat normal but damn.